Merge pull request #1876 from restic/forget-explain

forget: Add --explain

Gopkg.lock

@@ -104,10 +104,11 @@
   version = "v1.1.0"
 
 [[projects]]
-  digest = "1:2e3c336fc7fde5c984d2841455a658a6d626450b1754a854b3b32e7a8f49a07a"
+  digest = "1:d2754cafcab0d22c13541618a8029a70a8959eb3525ff201fe971637e2274cd0"
   name = "github.com/google/go-cmp"
   packages = [
     "cmp",
+    "cmp/cmpopts",
     "cmp/internal/diff",
     "cmp/internal/function",
     "cmp/internal/value",
@@ -449,6 +450,7 @@
     "github.com/cenkalti/backoff",
     "github.com/elithrar/simple-scrypt",
     "github.com/google/go-cmp/cmp",
+    "github.com/google/go-cmp/cmp/cmpopts",
     "github.com/juju/ratelimit",
     "github.com/kurin/blazer/b2",
     "github.com/mattn/go-isatty",

changelog/unreleased/pull-1876

@@ -0,0 +1,7 @@
+Enhancement: Display reason why forget keeps snapshots
+
+We've added a column to the list of snapshots `forget` keeps which details the
+reasons to keep a particuliar snapshot. This makes debugging policies for
+forget much easier. Please remember to always try things out with `--dry-run`!
+
+https://github.com/restic/restic/pull/1876

cmd/restic/cmd_cache.go

@@ -9,6 +9,7 @@ import (
 	"github.com/restic/restic/internal/cache"
 	"github.com/restic/restic/internal/errors"
 	"github.com/restic/restic/internal/fs"
+	"github.com/restic/restic/internal/ui/table"
 	"github.com/spf13/cobra"
 )
 
@@ -85,9 +86,17 @@ func runCache(opts CacheOptions, gopts GlobalOptions, args []string) error {
 		return nil
 	}
 
-	tab := NewTable()
-	tab.Header = fmt.Sprintf("%-14s   %-16s %s", "Repository ID", "Last Used", "Old")
-	tab.RowFormat = "%-14s   %-16s %s"
+	tab := table.New()
+
+	type data struct {
+		ID   string
+		Last string
+		Old  string
+	}
+
+	tab.AddColumn("Repo ID", "{{ .ID }}")
+	tab.AddColumn("Last Used", "{{ .Last }}")
+	tab.AddColumn("Old", "{{ .Old }}")
 
 	dirs, err := cache.All(cachedir)
 	if err != nil {
@@ -109,7 +118,7 @@ func runCache(opts CacheOptions, gopts GlobalOptions, args []string) error {
 			old = "yes"
 		}
 
-		tab.Rows = append(tab.Rows, []interface{}{
+		tab.AddRow(data{
 			entry.Name()[:10],
 			fmt.Sprintf("%d days ago", uint(time.Since(entry.ModTime()).Hours()/24)),
 			old,

cmd/restic/cmd_forget.go

@@ -206,17 +206,17 @@ func runForget(opts ForgetOptions, gopts GlobalOptions, args []string) error {
 			}
 			Verbosef(":\n\n")
 
-			keep, remove := restic.ApplyPolicy(snapshotGroup, policy)
+			keep, remove, reasons := restic.ApplyPolicy(snapshotGroup, policy)
 
 			if len(keep) != 0 && !gopts.Quiet {
 				Printf("keep %d snapshots:\n", len(keep))
-				PrintSnapshots(globalOptions.stdout, keep, opts.Compact)
+				PrintSnapshots(globalOptions.stdout, keep, reasons, opts.Compact)
 				Printf("\n")
 			}
 
 			if len(remove) != 0 && !gopts.Quiet {
 				Printf("remove %d snapshots:\n", len(remove))
-				PrintSnapshots(globalOptions.stdout, remove, opts.Compact)
+				PrintSnapshots(globalOptions.stdout, remove, nil, opts.Compact)
 				Printf("\n")
 			}
 

cmd/restic/cmd_key.go

@@ -3,7 +3,6 @@ package main
 import (
 	"context"
 	"encoding/json"
-	"fmt"
 	"io/ioutil"
 	"os"
 	"strings"
@@ -11,6 +10,7 @@ import (
 	"github.com/restic/restic/internal/errors"
 	"github.com/restic/restic/internal/repository"
 	"github.com/restic/restic/internal/restic"
+	"github.com/restic/restic/internal/ui/table"
 
 	"github.com/spf13/cobra"
 )
@@ -36,53 +36,18 @@ func init() {
 	flags.StringVarP(&newPasswordFile, "new-password-file", "", "", "the file from which to load a new password")
 }
 
-type keyInfo struct {
-	Current  bool   `json:"current"`
-	ID       string `json:"id"`
-	UserName string `json:"userName"`
-	HostName string `json:"hostName"`
-	Created  string `json:"created"`
-}
-
-func (ki keyInfo) CurrentStr() string {
-	if ki.Current {
-		return "*"
-	}
-	return " "
-}
-
 func listKeys(ctx context.Context, s *repository.Repository, gopts GlobalOptions) error {
-	var (
-		appendKey func(keyInfo)
-		printKeys func() error
-	)
-
-	switch gopts.JSON {
-	case true:
-		var keys []keyInfo
-
-		appendKey = func(key keyInfo) {
-			keys = append(keys, key)
-		}
-
-		printKeys = func() error {
-			return json.NewEncoder(gopts.stdout).Encode(keys)
-		}
-	default:
-		tab := NewTable()
-		tab.Header = fmt.Sprintf(" %-10s  %-10s  %-10s  %s", "ID", "User", "Host", "Created")
-		tab.RowFormat = "%s%-10s  %-10s  %-10s  %s"
-
-		appendKey = func(key keyInfo) {
-			tab.Rows = append(tab.Rows, []interface{}{key.CurrentStr(), key.ID, key.UserName, key.HostName, key.Created})
-		}
-
-		printKeys = func() error {
-			return tab.Write(globalOptions.stdout)
-		}
+	type keyInfo struct {
+		Current  bool   `json:"current"`
+		ID       string `json:"id"`
+		UserName string `json:"userName"`
+		HostName string `json:"hostName"`
+		Created  string `json:"created"`
 	}
 
-	if err := s.List(ctx, restic.KeyFile, func(id restic.ID, size int64) error {
+	var keys []keyInfo
+
+	err := s.List(ctx, restic.KeyFile, func(id restic.ID, size int64) error {
 		k, err := repository.LoadKey(ctx, s, id.String())
 		if err != nil {
 			Warnf("LoadKey() failed: %v\n", err)
@@ -97,14 +62,29 @@ func listKeys(ctx context.Context, s *repository.Repository, gopts GlobalOptions
 			Created:  k.Created.Format(TimeFormat),
 		}
 
-		appendKey(key)
-
+		keys = append(keys, key)
 		return nil
-	}); err != nil {
+	})
+
+	if err != nil {
 		return err
 	}
 
-	return printKeys()
+	if gopts.JSON {
+		return json.NewEncoder(globalOptions.stdout).Encode(keys)
+	}
+
+	tab := table.New()
+	tab.AddColumn(" ID", "{{if .Current}}*{{else}} {{end}}{{ .ID }}")
+	tab.AddColumn("User", "{{ .UserName }}")
+	tab.AddColumn("Host", "{{ .HostName }}")
+	tab.AddColumn("Created", "{{ .Created }}")
+
+	for _, key := range keys {
+		tab.AddRow(key)
+	}
+
+	return tab.Write(globalOptions.stdout)
 }
 
 // testKeyNewPassword is used to set a new password during integration testing.

cmd/restic/cmd_snapshots.go

@@ -9,6 +9,7 @@ import (
 	"strings"
 
 	"github.com/restic/restic/internal/restic"
+	"github.com/restic/restic/internal/ui/table"
 	"github.com/spf13/cobra"
 )
 
@@ -81,7 +82,7 @@ func runSnapshots(opts SnapshotOptions, gopts GlobalOptions, args []string) erro
 		}
 		return nil
 	}
-	PrintSnapshots(gopts.stdout, list, opts.Compact)
+	PrintSnapshots(gopts.stdout, list, nil, opts.Compact)
 
 	return nil
 }
@@ -123,7 +124,16 @@ func FilterLastSnapshots(list restic.Snapshots) restic.Snapshots {
 }
 
 // PrintSnapshots prints a text table of the snapshots in list to stdout.
-func PrintSnapshots(stdout io.Writer, list restic.Snapshots, compact bool) {
+func PrintSnapshots(stdout io.Writer, list restic.Snapshots, reasons []restic.KeepReason, compact bool) {
+	// keep the reasons a snasphot is being kept in a map, so that it doesn't
+	// get lost when the list of snapshots is sorted
+	keepReasons := make(map[restic.ID]restic.KeepReason, len(reasons))
+	if len(reasons) > 0 {
+		for i, sn := range list {
+			id := sn.ID()
+			keepReasons[*id] = reasons[i]
+		}
+	}
 
 	// always sort the snapshots so that the newer ones are listed last
 	sort.SliceStable(list, func(i, j int) bool {
@@ -143,71 +153,72 @@ func PrintSnapshots(stdout io.Writer, list restic.Snapshots, compact bool) {
 		}
 	}
 
-	tab := NewTable()
-	if !compact {
-		tab.Header = fmt.Sprintf("%-8s  %-19s  %-*s  %-*s  %-3s %s", "ID", "Date", -maxHost, "Host", -maxTag, "Tags", "", "Directory")
-		tab.RowFormat = fmt.Sprintf("%%-8s  %%-19s  %%%ds  %%%ds  %%-3s %%s", -maxHost, -maxTag)
+	tab := table.New()
+
+	if compact {
+		tab.AddColumn("ID", "{{ .ID }}")
+		tab.AddColumn("Time", "{{ .Timestamp }}")
+		tab.AddColumn("Host", "{{ .Hostname }}")
+		tab.AddColumn("Tags  ", `{{ join .Tags "\n" }}`)
 	} else {
-		tab.Header = fmt.Sprintf("%-8s  %-19s  %-*s  %-*s", "ID", "Date", -maxHost, "Host", -maxTag, "Tags")
-		tab.RowFormat = fmt.Sprintf("%%-8s  %%-19s  %%%ds  %%s", -maxHost)
+		tab.AddColumn("ID", "{{ .ID }}")
+		tab.AddColumn("Time", "{{ .Timestamp }}")
+		tab.AddColumn("Host      ", "{{ .Hostname }}")
+		tab.AddColumn("Tags      ", `{{ join .Tags "," }}`)
+		if len(reasons) > 0 {
+			tab.AddColumn("Reasons", `{{ join .Reasons "\n" }}`)
+		}
+		tab.AddColumn("Paths", `{{ join .Paths "\n" }}`)
 	}
 
+	type snapshot struct {
+		ID        string
+		Timestamp string
+		Hostname  string
+		Tags      []string
+		Reasons   []string
+		Paths     []string
+	}
+
+	var multiline bool
 	for _, sn := range list {
-		if len(sn.Paths) == 0 {
-			continue
+		data := snapshot{
+			ID:        sn.ID().Str(),
+			Timestamp: sn.Time.Format(TimeFormat),
+			Hostname:  sn.Hostname,
+			Tags:      sn.Tags,
+			Paths:     sn.Paths,
 		}
 
-		firstTag := ""
-		if len(sn.Tags) > 0 {
-			firstTag = sn.Tags[0]
+		if len(reasons) > 0 {
+			id := sn.ID()
+			data.Reasons = keepReasons[*id].Matches
 		}
 
-		rows := len(sn.Paths)
-		if rows < len(sn.Tags) {
-			rows = len(sn.Tags)
+		if len(sn.Paths) > 1 {
+			multiline = true
 		}
 
-		treeElement := "   "
-		if rows != 1 {
-			treeElement = "┌──"
-		}
-
-		if !compact {
-			tab.Rows = append(tab.Rows, []interface{}{sn.ID().Str(), sn.Time.Format(TimeFormat), sn.Hostname, firstTag, treeElement, sn.Paths[0]})
-		} else {
-			allTags := ""
-			for _, tag := range sn.Tags {
-				allTags += tag + " "
-			}
-			tab.Rows = append(tab.Rows, []interface{}{sn.ID().Str(), sn.Time.Format(TimeFormat), sn.Hostname, allTags})
-			continue
-		}
-
-		if len(sn.Tags) > rows {
-			rows = len(sn.Tags)
-		}
-
-		for i := 1; i < rows; i++ {
-			path := ""
-			if len(sn.Paths) > i {
-				path = sn.Paths[i]
-			}
-
-			tag := ""
-			if len(sn.Tags) > i {
-				tag = sn.Tags[i]
-			}
-
-			treeElement := "│"
-			if i == (rows - 1) {
-				treeElement = "└──"
-			}
-
-			tab.Rows = append(tab.Rows, []interface{}{"", "", "", tag, treeElement, path})
-		}
+		tab.AddRow(data)
 	}
 
-	tab.Footer = fmt.Sprintf("%d snapshots", len(list))
+	tab.AddFooter(fmt.Sprintf("%d snapshots", len(list)))
+
+	if multiline {
+		// print an additional blank line between snapshots
+
+		var last int
+		tab.PrintData = func(w io.Writer, idx int, s string) error {
+			var err error
+			if idx == last {
+				_, err = fmt.Fprintf(w, "%s\n", s)
+			} else {
+				_, err = fmt.Fprintf(w, "\n%s\n", s)
+			}
+			last = idx
+			return err
+		}
+	}
 
 	tab.Write(stdout)
 }

cmd/restic/global.go

@@ -38,6 +38,9 @@ import (
 
 var version = "0.9.2-dev (compiled manually)"
 
+// TimeFormat is the format used for all timestamps printed by restic.
+const TimeFormat = "2006-01-02 15:04:05"
+
 // GlobalOptions hold all global options for restic.
 type GlobalOptions struct {
 	Repo          string

cmd/restic/table.go

@@ -1,63 +0,0 @@
-package main
-
-import (
-	"fmt"
-	"io"
-	"strings"
-)
-
-// Table contains data for a table to be printed.
-type Table struct {
-	Header string
-	Rows   [][]interface{}
-	Footer string
-
-	RowFormat string
-}
-
-// NewTable initializes a new Table.
-func NewTable() Table {
-	return Table{
-		Rows: [][]interface{}{},
-	}
-}
-
-func (t Table) printSeparationLine(w io.Writer) error {
-	_, err := fmt.Fprintln(w, strings.Repeat("-", 70))
-	return err
-}
-
-// Write prints the table to w.
-func (t Table) Write(w io.Writer) error {
-	_, err := fmt.Fprintln(w, t.Header)
-	if err != nil {
-		return err
-	}
-
-	err = t.printSeparationLine(w)
-	if err != nil {
-		return err
-	}
-
-	for _, row := range t.Rows {
-		_, err = fmt.Fprintf(w, t.RowFormat+"\n", row...)
-		if err != nil {
-			return err
-		}
-	}
-
-	err = t.printSeparationLine(w)
-	if err != nil {
-		return err
-	}
-
-	_, err = fmt.Fprintln(w, t.Footer)
-	if err != nil {
-		return err
-	}
-
-	return nil
-}
-
-// TimeFormat is the format used for all timestamps printed by restic.
-const TimeFormat = "2006-01-02 15:04:05"

internal/restic/snapshot_policy.go

@@ -6,6 +6,8 @@ import (
 	"sort"
 	"strings"
 	"time"
+
+	"github.com/restic/restic/internal/debug"
 )
 
 // ExpirePolicy configures which snapshots should be automatically removed.
@@ -125,41 +127,70 @@ func findLatestTimestamp(list Snapshots) time.Time {
 	return latest
 }
 
+// KeepReason specifies why a particular snapshot was kept, and the counters at
+// that point in the policy evaluation.
+type KeepReason struct {
+	Snapshot *Snapshot `json:"snapshot"`
+
+	// description text which criteria match, e.g. "daily", "monthly"
+	Matches []string `json:"matches"`
+
+	// the counters after evaluating the current snapshot
+	Counters struct {
+		Last    int `json:"last,omitempty"`
+		Hourly  int `json:"hourly,omitempty"`
+		Daily   int `json:"daily,omitempty"`
+		Weekly  int `json:"weekly,omitempty"`
+		Monthly int `json:"monthly,omitempty"`
+		Yearly  int `json:"yearly,omitempty"`
+	} `json:"counters"`
+}
+
 // ApplyPolicy returns the snapshots from list that are to be kept and removed
-// according to the policy p. list is sorted in the process.
-func ApplyPolicy(list Snapshots, p ExpirePolicy) (keep, remove Snapshots) {
+// according to the policy p. list is sorted in the process. reasons contains
+// the reasons to keep each snapshot, it is in the same order as keep.
+func ApplyPolicy(list Snapshots, p ExpirePolicy) (keep, remove Snapshots, reasons []KeepReason) {
 	sort.Sort(list)
 
 	if p.Empty() {
-		return list, remove
+		for _, sn := range list {
+			reasons = append(reasons, KeepReason{
+				Snapshot: sn,
+				Matches:  []string{"policy is empty"},
+			})
+		}
+		return list, remove, reasons
 	}
 
 	if len(list) == 0 {
-		return list, remove
+		return list, nil, nil
 	}
 
 	var buckets = [6]struct {
 		Count  int
 		bucker func(d time.Time, nr int) int
 		Last   int
+		reason string
 	}{
-		{p.Last, always, -1},
-		{p.Hourly, ymdh, -1},
-		{p.Daily, ymd, -1},
-		{p.Weekly, yw, -1},
-		{p.Monthly, ym, -1},
-		{p.Yearly, y, -1},
+		{p.Last, always, -1, "last snapshot"},
+		{p.Hourly, ymdh, -1, "hourly snapshot"},
+		{p.Daily, ymd, -1, "daily snapshot"},
+		{p.Weekly, yw, -1, "weekly snapshot"},
+		{p.Monthly, ym, -1, "monthly snapshot"},
+		{p.Yearly, y, -1, "yearly snapshot"},
 	}
 
 	latest := findLatestTimestamp(list)
 
 	for nr, cur := range list {
 		var keepSnap bool
+		var keepSnapReasons []string
 
 		// Tags are handled specially as they are not counted.
 		for _, l := range p.Tags {
 			if cur.HasTags(l) {
 				keepSnap = true
+				keepSnapReasons = append(keepSnapReasons, fmt.Sprintf("has tags %v", l))
 			}
 		}
 
@@ -168,6 +199,7 @@ func ApplyPolicy(list Snapshots, p ExpirePolicy) (keep, remove Snapshots) {
 			t := latest.AddDate(-p.Within.Years, -p.Within.Months, -p.Within.Days)
 			if cur.Time.After(t) {
 				keepSnap = true
+				keepSnapReasons = append(keepSnapReasons, fmt.Sprintf("within %v", p.Within))
 			}
 		}
 
@@ -176,19 +208,32 @@ func ApplyPolicy(list Snapshots, p ExpirePolicy) (keep, remove Snapshots) {
 			if b.Count > 0 {
 				val := b.bucker(cur.Time, nr)
 				if val != b.Last {
+					debug.Log("keep %v %v, bucker %v, val %v\n", cur.Time, cur.id.Str(), i, val)
 					keepSnap = true
 					buckets[i].Last = val
 					buckets[i].Count--
+					keepSnapReasons = append(keepSnapReasons, b.reason)
 				}
 			}
 		}
 
 		if keepSnap {
 			keep = append(keep, cur)
+			kr := KeepReason{
+				Snapshot: cur,
+				Matches:  keepSnapReasons,
+			}
+			kr.Counters.Last = buckets[0].Count
+			kr.Counters.Hourly = buckets[1].Count
+			kr.Counters.Daily = buckets[2].Count
+			kr.Counters.Weekly = buckets[3].Count
+			kr.Counters.Monthly = buckets[4].Count
+			kr.Counters.Yearly = buckets[5].Count
+			reasons = append(reasons, kr)
 		} else {
 			remove = append(remove, cur)
 		}
 	}
 
-	return keep, remove
+	return keep, remove, reasons
 }

internal/restic/snapshot_policy_test.go

@@ -5,10 +5,11 @@ import (
 	"fmt"
 	"io/ioutil"
 	"path/filepath"
-	"reflect"
 	"testing"
 	"time"
 
+	"github.com/google/go-cmp/cmp"
+	"github.com/google/go-cmp/cmp/cmpopts"
 	"github.com/restic/restic/internal/restic"
 )
 
@@ -52,6 +53,43 @@ func TestExpireSnapshotOps(t *testing.T) {
 	}
 }
 
+// ApplyPolicyResult is used to marshal/unmarshal the golden files for
+// TestApplyPolicy.
+type ApplyPolicyResult struct {
+	Keep    restic.Snapshots    `json:"keep"`
+	Reasons []restic.KeepReason `json:"reasons,omitempty"`
+}
+
+func loadGoldenFile(t testing.TB, filename string) (res ApplyPolicyResult) {
+	buf, err := ioutil.ReadFile(filename)
+	if err != nil {
+		t.Fatalf("error loading golden file %v: %v", filename, err)
+	}
+
+	err = json.Unmarshal(buf, &res)
+	if err != nil {
+		t.Fatalf("error unmarshalling golden file %v: %v", filename, err)
+	}
+
+	return res
+}
+
+func saveGoldenFile(t testing.TB, filename string, keep restic.Snapshots, reasons []restic.KeepReason) {
+	res := ApplyPolicyResult{
+		Keep:    keep,
+		Reasons: reasons,
+	}
+
+	buf, err := json.MarshalIndent(res, "", "  ")
+	if err != nil {
+		t.Fatalf("error marshaling result: %v", err)
+	}
+
+	if err = ioutil.WriteFile(filename, buf, 0644); err != nil {
+		t.Fatalf("unable to update golden file: %v", err)
+	}
+}
+
 func TestApplyPolicy(t *testing.T) {
 	var testExpireSnapshots = restic.Snapshots{
 		{Time: parseTimeUTC("2014-09-01 10:20:30")},
@@ -191,10 +229,8 @@ func TestApplyPolicy(t *testing.T) {
 
 	for i, p := range tests {
 		t.Run("", func(t *testing.T) {
-			keep, remove := restic.ApplyPolicy(testExpireSnapshots, p)
 
-			t.Logf("returned keep %v, remove %v (of %v) expired snapshots for policy %v",
-				len(keep), len(remove), len(testExpireSnapshots), p)
+			keep, remove, reasons := restic.ApplyPolicy(testExpireSnapshots, p)
 
 			if len(keep)+len(remove) != len(testExpireSnapshots) {
 				t.Errorf("len(keep)+len(remove) = %d != len(testExpireSnapshots) = %d",
@@ -206,39 +242,26 @@ func TestApplyPolicy(t *testing.T) {
 					p.Sum(), len(keep))
 			}
 
-			for _, sn := range keep {
-				t.Logf("    keep snapshot at %v %s", sn.Time, sn.Tags)
-			}
-			for _, sn := range remove {
-				t.Logf("    forget snapshot at %v %s", sn.Time, sn.Tags)
+			if len(keep) != len(reasons) {
+				t.Errorf("got %d keep reasons for %d snapshots to keep, these must be equal", len(reasons), len(keep))
 			}
 
 			goldenFilename := filepath.Join("testdata", fmt.Sprintf("policy_keep_snapshots_%d", i))
 
 			if *updateGoldenFiles {
-				buf, err := json.MarshalIndent(keep, "", "  ")
-				if err != nil {
-					t.Fatalf("error marshaling result: %v", err)
-				}
-
-				if err = ioutil.WriteFile(goldenFilename, buf, 0644); err != nil {
-					t.Fatalf("unable to update golden file: %v", err)
-				}
+				saveGoldenFile(t, goldenFilename, keep, reasons)
 			}
 
-			buf, err := ioutil.ReadFile(goldenFilename)
-			if err != nil {
-				t.Fatalf("error loading golden file %v: %v", goldenFilename, err)
+			want := loadGoldenFile(t, goldenFilename)
+
+			cmpOpts := cmpopts.IgnoreUnexported(restic.Snapshot{})
+
+			if !cmp.Equal(want.Keep, keep, cmpOpts) {
+				t.Error(cmp.Diff(want.Keep, keep, cmpOpts))
 			}
 
-			var want restic.Snapshots
-			err = json.Unmarshal(buf, &want)
-			if err != nil {
-				t.Fatalf("error unmarshalling golden file %v: %v", goldenFilename, err)
-			}
-
-			if !reflect.DeepEqual(keep, want) {
-				t.Fatalf("wrong result, want:\n  %v\ngot:\n  %v", want, keep)
+			if !cmp.Equal(want.Reasons, reasons, cmpOpts) {
+				t.Error(cmp.Diff(want.Reasons, reasons, cmpOpts))
 			}
 		})
 	}

internal/restic/testdata/policy_keep_snapshots_1

@@ -1,52 +1,184 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-12T21:08:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-12T21:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-09T21:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-08T20:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-07T10:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-06T08:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-05T09:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-04T16:23:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-04T12:30:03Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:08:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-09T21:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-08T20:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-07T10:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-06T08:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-05T09:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-04T16:23:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-04T12:30:03Z",
+      "tree": null,
+      "paths": null
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2016-01-18T12:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 9
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-12T21:08:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 8
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-12T21:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 7
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-09T21:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 6
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-08T20:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 5
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-07T10:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 4
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-06T08:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 3
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-05T09:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 2
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T16:23:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 1
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T12:30:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_10

@@ -1,52 +1,187 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-12T21:08:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-09T21:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-08T20:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-07T10:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-06T08:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-05T09:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-04T16:23:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-03T07:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-01T07:08:03Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:08:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-09T21:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-08T20:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-07T10:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-06T08:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-05T09:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-04T16:23:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-03T07:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-01T07:08:03Z",
+      "tree": null,
+      "paths": null
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2016-01-18T12:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot",
+        "daily snapshot"
+      ],
+      "counters": {
+        "last": 1,
+        "daily": 9
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-12T21:08:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot",
+        "daily snapshot"
+      ],
+      "counters": {
+        "daily": 8
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-09T21:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot"
+      ],
+      "counters": {
+        "daily": 7
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-08T20:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot"
+      ],
+      "counters": {
+        "daily": 6
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-07T10:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot"
+      ],
+      "counters": {
+        "daily": 5
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-06T08:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot"
+      ],
+      "counters": {
+        "daily": 4
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-05T09:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot"
+      ],
+      "counters": {
+        "daily": 3
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T16:23:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot"
+      ],
+      "counters": {
+        "daily": 2
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-03T07:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot"
+      ],
+      "counters": {
+        "daily": 1
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-01T07:08:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_11

@@ -1,12 +1,40 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-12T21:08:03Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:08:03Z",
+      "tree": null,
+      "paths": null
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2016-01-18T12:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "weekly snapshot"
+      ],
+      "counters": {
+        "weekly": 1
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-12T21:08:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "weekly snapshot"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_12

@@ -1,22 +1,76 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-12T21:08:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-09T21:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-03T07:02:03Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:08:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-09T21:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-03T07:02:03Z",
+      "tree": null,
+      "paths": null
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2016-01-18T12:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "weekly snapshot"
+      ],
+      "counters": {
+        "weekly": 3
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-12T21:08:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "weekly snapshot"
+      ],
+      "counters": {
+        "weekly": 2
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-09T21:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "weekly snapshot"
+      ],
+      "counters": {
+        "weekly": 1
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-03T07:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "weekly snapshot"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_13

@@ -1,22 +1,81 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-12T21:08:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-09T21:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-03T07:02:03Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:08:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-09T21:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-03T07:02:03Z",
+      "tree": null,
+      "paths": null
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2016-01-18T12:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot",
+        "weekly snapshot"
+      ],
+      "counters": {
+        "daily": 2,
+        "weekly": 3
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-12T21:08:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot",
+        "weekly snapshot"
+      ],
+      "counters": {
+        "daily": 1,
+        "weekly": 2
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-09T21:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot",
+        "weekly snapshot"
+      ],
+      "counters": {
+        "weekly": 1
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-03T07:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "weekly snapshot"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_14

@@ -1,32 +1,112 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2015-11-22T10:20:30Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2015-10-22T10:20:30Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2015-09-22T10:20:30Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2015-08-22T10:20:30Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2014-11-22T10:20:30Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2015-11-22T10:20:30Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2015-10-22T10:20:30Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2015-09-22T10:20:30Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2015-08-22T10:20:30Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2014-11-22T10:20:30Z",
+      "tree": null,
+      "paths": null
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2016-01-18T12:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "monthly snapshot"
+      ],
+      "counters": {
+        "monthly": 5
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2015-11-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "monthly snapshot"
+      ],
+      "counters": {
+        "monthly": 4
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2015-10-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "monthly snapshot"
+      ],
+      "counters": {
+        "monthly": 3
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2015-09-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "monthly snapshot"
+      ],
+      "counters": {
+        "monthly": 2
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2015-08-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "monthly snapshot"
+      ],
+      "counters": {
+        "monthly": 1
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "monthly snapshot"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_15

@@ -1,37 +1,135 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-12T21:08:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2015-11-22T10:20:30Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2015-10-22T10:20:30Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2015-09-22T10:20:30Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2015-08-22T10:20:30Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2014-11-22T10:20:30Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:08:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2015-11-22T10:20:30Z",
+      "tree": null,
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+    },
+    {
+      "time": "2015-10-22T10:20:30Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2015-09-22T10:20:30Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2015-08-22T10:20:30Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2014-11-22T10:20:30Z",
+      "tree": null,
+      "paths": null
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2016-01-18T12:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot",
+        "weekly snapshot",
+        "monthly snapshot"
+      ],
+      "counters": {
+        "daily": 1,
+        "weekly": 1,
+        "monthly": 5
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-12T21:08:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot",
+        "weekly snapshot"
+      ],
+      "counters": {
+        "monthly": 5
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2015-11-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "monthly snapshot"
+      ],
+      "counters": {
+        "monthly": 4
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2015-10-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "monthly snapshot"
+      ],
+      "counters": {
+        "monthly": 3
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2015-09-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "monthly snapshot"
+      ],
+      "counters": {
+        "monthly": 2
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2015-08-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "monthly snapshot"
+      ],
+      "counters": {
+        "monthly": 1
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "monthly snapshot"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_16

@@ -1,17 +1,60 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2015-11-22T10:20:30Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2014-11-22T10:20:30Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2015-11-22T10:20:30Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2014-11-22T10:20:30Z",
+      "tree": null,
+      "paths": null
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2016-01-18T12:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "yearly snapshot"
+      ],
+      "counters": {
+        "yearly": 9
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2015-11-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "yearly snapshot"
+      ],
+      "counters": {
+        "yearly": 8
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "yearly snapshot"
+      ],
+      "counters": {
+        "yearly": 7
+      }
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_17

@@ -1,52 +1,206 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-12T21:08:03Z",
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-  {
-    "time": "2016-01-09T21:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-08T20:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-07T10:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-06T08:02:03Z",
-    "tree": null,
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-  },
-  {
-    "time": "2016-01-05T09:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2015-11-22T10:20:30Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2015-10-22T10:20:30Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2014-11-22T10:20:30Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:08:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-09T21:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-08T20:02:03Z",
+      "tree": null,
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+    },
+    {
+      "time": "2016-01-07T10:02:03Z",
+      "tree": null,
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+    },
+    {
+      "time": "2016-01-06T08:02:03Z",
+      "tree": null,
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+    },
+    {
+      "time": "2016-01-05T09:02:03Z",
+      "tree": null,
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+    },
+    {
+      "time": "2015-11-22T10:20:30Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2015-10-22T10:20:30Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2014-11-22T10:20:30Z",
+      "tree": null,
+      "paths": null
+    }
+  ],
+  "reasons": [
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+        "time": "2016-01-18T12:02:03Z",
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+      },
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+        "daily snapshot",
+        "weekly snapshot",
+        "monthly snapshot",
+        "yearly snapshot"
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+        "yearly": 9
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-12T21:08:03Z",
+        "tree": null,
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+      },
+      "matches": [
+        "daily snapshot",
+        "weekly snapshot"
+      ],
+      "counters": {
+        "daily": 5,
+        "monthly": 2,
+        "yearly": 9
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-09T21:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot"
+      ],
+      "counters": {
+        "daily": 4,
+        "monthly": 2,
+        "yearly": 9
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-08T20:02:03Z",
+        "tree": null,
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+      },
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+        "daily snapshot"
+      ],
+      "counters": {
+        "daily": 3,
+        "monthly": 2,
+        "yearly": 9
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-07T10:02:03Z",
+        "tree": null,
+        "paths": null
+      },
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+        "daily snapshot"
+      ],
+      "counters": {
+        "daily": 2,
+        "monthly": 2,
+        "yearly": 9
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-06T08:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot"
+      ],
+      "counters": {
+        "daily": 1,
+        "monthly": 2,
+        "yearly": 9
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-05T09:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot"
+      ],
+      "counters": {
+        "monthly": 2,
+        "yearly": 9
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2015-11-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "monthly snapshot",
+        "yearly snapshot"
+      ],
+      "counters": {
+        "monthly": 1,
+        "yearly": 8
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2015-10-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "monthly snapshot"
+      ],
+      "counters": {
+        "yearly": 8
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "yearly snapshot"
+      ],
+      "counters": {
+        "yearly": 7
+      }
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_18

@@ -1,153 +1,416 @@
-[
-  {
-    "time": "2015-10-22T10:20:30Z",
-    "tree": null,
-    "paths": [
-      "path1",
-      "path2"
-    ],
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-      "foo",
-      "bar"
-    ]
-  },
-  {
-    "time": "2015-10-22T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo",
-      "bar"
-    ]
-  },
-  {
-    "time": "2015-10-22T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo",
-      "bar"
-    ]
-  },
-  {
-    "time": "2014-11-15T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo",
-      "bar"
-    ]
-  },
-  {
-    "time": "2014-11-13T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-11-12T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
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-  {
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-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-11-08T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
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-  },
-  {
-    "time": "2014-10-22T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
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-  },
-  {
-    "time": "2014-10-20T10:20:30Z",
-    "tree": null,
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-    "tags": [
-      "foo"
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-  {
-    "time": "2014-10-11T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
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-  },
-  {
-    "time": "2014-10-10T10:20:30Z",
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-    "tags": [
-      "foo"
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-  },
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-    "time": "2014-10-09T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
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-  {
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-    "tree": null,
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-  {
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-    "tree": null,
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-    "tags": [
-      "foo"
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-  },
-  {
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-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-10-02T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-10-01T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2015-10-22T10:20:30Z",
+      "tree": null,
+      "paths": [
+        "path1",
+        "path2"
+      ],
+      "tags": [
+        "foo",
+        "bar"
+      ]
+    },
+    {
+      "time": "2015-10-22T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo",
+        "bar"
+      ]
+    },
+    {
+      "time": "2015-10-22T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo",
+        "bar"
+      ]
+    },
+    {
+      "time": "2014-11-15T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo",
+        "bar"
+      ]
+    },
+    {
+      "time": "2014-11-13T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-11-12T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-11-10T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-11-08T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-22T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-20T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-11T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-10T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-09T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-08T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-06T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-05T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-02T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-01T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2015-10-22T10:20:30Z",
+        "tree": null,
+        "paths": [
+          "path1",
+          "path2"
+        ],
+        "tags": [
+          "foo",
+          "bar"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2015-10-22T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo",
+          "bar"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2015-10-22T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo",
+          "bar"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-15T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo",
+          "bar"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-13T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-12T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-10T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-08T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-22T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-20T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-11T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-10T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-09T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-08T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-06T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-05T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-02T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-01T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_19

@@ -1,41 +1,108 @@
-[
-  {
-    "time": "2015-10-22T10:20:30Z",
-    "tree": null,
-    "paths": [
-      "path1",
-      "path2"
-    ],
-    "tags": [
-      "foo",
-      "bar"
-    ]
-  },
-  {
-    "time": "2015-10-22T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo",
-      "bar"
-    ]
-  },
-  {
-    "time": "2015-10-22T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo",
-      "bar"
-    ]
-  },
-  {
-    "time": "2014-11-15T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo",
-      "bar"
-    ]
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2015-10-22T10:20:30Z",
+      "tree": null,
+      "paths": [
+        "path1",
+        "path2"
+      ],
+      "tags": [
+        "foo",
+        "bar"
+      ]
+    },
+    {
+      "time": "2015-10-22T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo",
+        "bar"
+      ]
+    },
+    {
+      "time": "2015-10-22T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo",
+        "bar"
+      ]
+    },
+    {
+      "time": "2014-11-15T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo",
+        "bar"
+      ]
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2015-10-22T10:20:30Z",
+        "tree": null,
+        "paths": [
+          "path1",
+          "path2"
+        ],
+        "tags": [
+          "foo",
+          "bar"
+        ]
+      },
+      "matches": [
+        "has tags [foo, bar]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2015-10-22T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo",
+          "bar"
+        ]
+      },
+      "matches": [
+        "has tags [foo, bar]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2015-10-22T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo",
+          "bar"
+        ]
+      },
+      "matches": [
+        "has tags [foo, bar]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-15T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo",
+          "bar"
+        ]
+      },
+      "matches": [
+        "has tags [foo, bar]"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_2

@@ -1,77 +1,274 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-12T21:08:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-12T21:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-09T21:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-08T20:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-07T10:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-06T08:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-05T09:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-04T16:23:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-04T12:30:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-04T12:28:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-04T12:24:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-04T12:23:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-04T11:23:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-04T10:23:03Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:08:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-09T21:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-08T20:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-07T10:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-06T08:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-05T09:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-04T16:23:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-04T12:30:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-04T12:28:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-04T12:24:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-04T12:23:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-04T11:23:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-04T10:23:03Z",
+      "tree": null,
+      "paths": null
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2016-01-18T12:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 14
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-12T21:08:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 13
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-12T21:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 12
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-09T21:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 11
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-08T20:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 10
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-07T10:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 9
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-06T08:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 8
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-05T09:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 7
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T16:23:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 6
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T12:30:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 5
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T12:28:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 4
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T12:24:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 3
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T12:23:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 2
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T11:23:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {
+        "last": 1
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T10:23:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_20

@@ -1,161 +1,442 @@
-[
-  {
-    "time": "2015-10-22T10:20:30Z",
-    "tree": null,
-    "paths": [
-      "path1",
-      "path2"
-    ],
-    "tags": [
-      "foo",
-      "bar"
-    ]
-  },
-  {
-    "time": "2015-10-22T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo",
-      "bar"
-    ]
-  },
-  {
-    "time": "2015-10-22T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo",
-      "bar"
-    ]
-  },
-  {
-    "time": "2014-11-15T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo",
-      "bar"
-    ]
-  },
-  {
-    "time": "2014-11-13T10:20:30.1Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "bar"
-    ]
-  },
-  {
-    "time": "2014-11-13T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-11-12T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-11-10T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-11-08T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-10-22T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-10-20T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-10-11T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-10-10T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-10-09T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-10-08T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-10-06T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-10-05T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-10-02T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  },
-  {
-    "time": "2014-10-01T10:20:30Z",
-    "tree": null,
-    "paths": null,
-    "tags": [
-      "foo"
-    ]
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2015-10-22T10:20:30Z",
+      "tree": null,
+      "paths": [
+        "path1",
+        "path2"
+      ],
+      "tags": [
+        "foo",
+        "bar"
+      ]
+    },
+    {
+      "time": "2015-10-22T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo",
+        "bar"
+      ]
+    },
+    {
+      "time": "2015-10-22T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo",
+        "bar"
+      ]
+    },
+    {
+      "time": "2014-11-15T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo",
+        "bar"
+      ]
+    },
+    {
+      "time": "2014-11-13T10:20:30.1Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "bar"
+      ]
+    },
+    {
+      "time": "2014-11-13T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-11-12T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-11-10T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-11-08T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-22T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-20T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-11T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-10T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-09T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-08T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-06T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-05T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-02T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    },
+    {
+      "time": "2014-10-01T10:20:30Z",
+      "tree": null,
+      "paths": null,
+      "tags": [
+        "foo"
+      ]
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2015-10-22T10:20:30Z",
+        "tree": null,
+        "paths": [
+          "path1",
+          "path2"
+        ],
+        "tags": [
+          "foo",
+          "bar"
+        ]
+      },
+      "matches": [
+        "has tags [foo]",
+        "has tags [bar]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2015-10-22T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo",
+          "bar"
+        ]
+      },
+      "matches": [
+        "has tags [foo]",
+        "has tags [bar]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2015-10-22T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo",
+          "bar"
+        ]
+      },
+      "matches": [
+        "has tags [foo]",
+        "has tags [bar]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-15T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo",
+          "bar"
+        ]
+      },
+      "matches": [
+        "has tags [foo]",
+        "has tags [bar]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-13T10:20:30.1Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "bar"
+        ]
+      },
+      "matches": [
+        "has tags [bar]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-13T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-12T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-10T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-11-08T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-22T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-20T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-11T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-10T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-09T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-08T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-06T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-05T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-02T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2014-10-01T10:20:30Z",
+        "tree": null,
+        "paths": null,
+        "tags": [
+          "foo"
+        ]
+      },
+      "matches": [
+        "has tags [foo]"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_21

@@ -1,7 +1,22 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2016-01-18T12:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1d"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_22

@@ -1,7 +1,22 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2016-01-18T12:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 2d"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_23

@@ -1,17 +1,54 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-12T21:08:03Z",
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-  },
-  {
-    "time": "2016-01-12T21:02:03Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:08:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:02:03Z",
+      "tree": null,
+      "paths": null
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2016-01-18T12:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 7d"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-12T21:08:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 7d"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-12T21:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 7d"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_24

@@ -1,97 +1,310 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
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-    "time": "2016-01-04T16:23:03Z",
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-    "time": "2016-01-04T12:30:03Z",
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-  {
-    "time": "2016-01-04T12:24:03Z",
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-    "time": "2016-01-04T12:23:03Z",
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-    "time": "2016-01-04T11:23:03Z",
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-    "time": "2016-01-01T07:08:03Z",
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-    "time": "2016-01-01T01:03:03Z",
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-  },
-  {
-    "time": "2016-01-01T01:02:03Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
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+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:08:03Z",
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+      "time": "2016-01-05T09:02:03Z",
+      "tree": null,
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+      "time": "2016-01-04T16:23:03Z",
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+    {
+      "time": "2016-01-04T12:30:03Z",
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+    },
+    {
+      "time": "2016-01-04T12:28:03Z",
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+      "time": "2016-01-04T12:24:03Z",
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+      "time": "2016-01-04T12:23:03Z",
+      "tree": null,
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+    },
+    {
+      "time": "2016-01-04T11:23:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-04T10:23:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-03T07:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-01T07:08:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-01T01:03:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-01T01:02:03Z",
+      "tree": null,
+      "paths": null
+    }
+  ],
+  "reasons": [
+    {
+      "snapshot": {
+        "time": "2016-01-18T12:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-12T21:08:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-12T21:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-09T21:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-08T20:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-07T10:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-06T08:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-05T09:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T16:23:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T12:30:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T12:28:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T12:24:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T12:23:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T11:23:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T10:23:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-03T07:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-01T07:08:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-01T01:03:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-01T01:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "within 1m"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_25

@@ -1,97 +1,310 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-12T21:08:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-12T21:02:03Z",
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-  },
-  {
-    "time": "2016-01-09T21:02:03Z",
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-  },
-  {
-    "time": "2016-01-08T20:02:03Z",
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-  },
-  {
-    "time": "2016-01-07T10:02:03Z",
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-    "paths": null
-  },
-  {
-    "time": "2016-01-06T08:02:03Z",
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-    "paths": null
-  },
-  {
-    "time": "2016-01-05T09:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-04T16:23:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-04T12:30:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
-    "time": "2016-01-04T12:28:03Z",
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-  },
-  {
-    "time": "2016-01-04T12:24:03Z",
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-    "paths": null
-  },
-  {
-    "time": "2016-01-04T12:23:03Z",
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-  },
-  {
-    "time": "2016-01-04T11:23:03Z",
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-  {
-    "time": "2016-01-03T07:02:03Z",
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-  },
-  {
-    "time": "2016-01-01T07:08:03Z",
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-    "paths": null
-  },
-  {
-    "time": "2016-01-01T01:03:03Z",
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-    "paths": null
-  },
-  {
-    "time": "2016-01-01T01:02:03Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:08:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-09T21:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-08T20:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-07T10:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-06T08:02:03Z",
+      "tree": null,
+      "paths": null
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+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_5

@@ -1,102 +1,364 @@
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+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_6

@@ -1,17 +1,58 @@
-[
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+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_7

@@ -1,52 +1,184 @@
-[
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+    {
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+        "time": "2016-01-05T09:02:03Z",
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+    },
+    {
+      "snapshot": {
+        "time": "2016-01-04T16:23:03Z",
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+    {
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+        "time": "2016-01-03T07:02:03Z",
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+      "matches": [
+        "daily snapshot"
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+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_8

@@ -1,152 +1,544 @@
-[
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-  {
-    "time": "2015-09-22T10:20:30Z",
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-]
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+    },
+    {
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+        "time": "2015-11-21T10:20:30Z",
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+      "matches": [
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+      }
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+    {
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+      }
+    },
+    {
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+        "time": "2015-11-18T10:20:30Z",
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+      }
+    },
+    {
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+      }
+    },
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+    {
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+    },
+    {
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+        "time": "2015-10-09T10:20:30Z",
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+      },
+      "matches": [
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+      "counters": {
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+      }
+    },
+    {
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+        "time": "2015-10-08T10:20:30Z",
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+      }
+    },
+    {
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+        "time": "2015-10-06T10:20:30Z",
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+      "counters": {
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+      }
+    },
+    {
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+        "paths": null
+      },
+      "matches": [
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+      }
+    },
+    {
+      "snapshot": {
+        "time": "2015-10-02T10:20:30Z",
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+        "paths": null
+      },
+      "matches": [
+        "daily snapshot"
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+      "counters": {
+        "daily": 2
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2015-10-01T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot"
+      ],
+      "counters": {
+        "daily": 1
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2015-09-22T10:20:30Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/restic/testdata/policy_keep_snapshots_9

@@ -1,32 +1,120 @@
-[
-  {
-    "time": "2016-01-18T12:02:03Z",
-    "tree": null,
-    "paths": null
-  },
-  {
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-  },
-  {
-    "time": "2016-01-07T10:02:03Z",
-    "tree": null,
-    "paths": null
-  }
-]
+{
+  "keep": [
+    {
+      "time": "2016-01-18T12:02:03Z",
+      "tree": null,
+      "paths": null
+    },
+    {
+      "time": "2016-01-12T21:08:03Z",
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+    },
+    {
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+    {
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+    }
+  ],
+  "reasons": [
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+      },
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+      }
+    },
+    {
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+        "paths": null
+      },
+      "matches": [
+        "last snapshot",
+        "daily snapshot"
+      ],
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+        "daily": 3
+      }
+    },
+    {
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+        "time": "2016-01-12T21:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot"
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+      "counters": {
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+        "daily": 3
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-09T21:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot",
+        "daily snapshot"
+      ],
+      "counters": {
+        "last": 1,
+        "daily": 2
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-08T20:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "last snapshot",
+        "daily snapshot"
+      ],
+      "counters": {
+        "daily": 1
+      }
+    },
+    {
+      "snapshot": {
+        "time": "2016-01-07T10:02:03Z",
+        "tree": null,
+        "paths": null
+      },
+      "matches": [
+        "daily snapshot"
+      ],
+      "counters": {}
+    }
+  ]
+}

internal/ui/table/table.go

@@ -0,0 +1,206 @@
+package table
+
+import (
+	"bytes"
+	"io"
+	"strings"
+
+	"text/template"
+)
+
+// Table contains data for a table to be printed.
+type Table struct {
+	columns   []string
+	templates []*template.Template
+	data      []interface{}
+	footer    []string
+
+	CellSeparator  string
+	PrintHeader    func(io.Writer, string) error
+	PrintSeparator func(io.Writer, string) error
+	PrintData      func(io.Writer, int, string) error
+	PrintFooter    func(io.Writer, string) error
+}
+
+var funcmap = template.FuncMap{
+	"join": strings.Join,
+}
+
+// New initializes a new Table
+func New() *Table {
+	p := func(w io.Writer, s string) error {
+		_, err := w.Write(append([]byte(s), '\n'))
+		return err
+	}
+	return &Table{
+		CellSeparator:  "  ",
+		PrintHeader:    p,
+		PrintSeparator: p,
+		PrintData: func(w io.Writer, _ int, s string) error {
+			return p(w, s)
+		},
+		PrintFooter: p,
+	}
+}
+
+// AddColumn adds a new header field with the header and format, which is
+// expected to be template string compatible with text/template. When compiling
+// the format fails, AddColumn panics.
+func (t *Table) AddColumn(header, format string) {
+	t.columns = append(t.columns, header)
+	tmpl, err := template.New("template for " + header).Funcs(funcmap).Parse(format)
+	if err != nil {
+		panic(err)
+	}
+
+	t.templates = append(t.templates, tmpl)
+}
+
+// AddRow adds a new row to the table, which is filled with data.
+func (t *Table) AddRow(data interface{}) {
+	t.data = append(t.data, data)
+}
+
+// AddFooter prints line after the table
+func (t *Table) AddFooter(line string) {
+	t.footer = append(t.footer, line)
+}
+
+func printLine(w io.Writer, print func(io.Writer, string) error, sep string, data []string, widths []int) error {
+	var fields [][]string
+
+	maxLines := 1
+	for _, d := range data {
+		lines := strings.Split(d, "\n")
+		if len(lines) > maxLines {
+			maxLines = len(lines)
+		}
+		fields = append(fields, lines)
+	}
+
+	for i := 0; i < maxLines; i++ {
+		var s string
+
+		for fieldNum, lines := range fields {
+			var v string
+
+			if i < len(lines) {
+				v += lines[i]
+			}
+
+			// apply padding
+			pad := widths[fieldNum] - len(v)
+			if pad > 0 {
+				v += strings.Repeat(" ", pad)
+			}
+
+			if fieldNum > 0 {
+				v = sep + v
+			}
+
+			s += v
+		}
+
+		err := print(w, strings.TrimRight(s, " "))
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// Write prints the table to w.
+func (t *Table) Write(w io.Writer) error {
+	columns := len(t.templates)
+	if columns == 0 {
+		return nil
+	}
+
+	// collect all data fields from all columns
+	lines := make([][]string, 0, len(t.data))
+	buf := bytes.NewBuffer(nil)
+
+	for _, data := range t.data {
+		row := make([]string, 0, len(t.templates))
+		for _, tmpl := range t.templates {
+			err := tmpl.Execute(buf, data)
+			if err != nil {
+				return err
+			}
+
+			row = append(row, string(buf.Bytes()))
+			buf.Reset()
+		}
+		lines = append(lines, row)
+	}
+
+	// find max width for each cell
+	columnWidths := make([]int, columns)
+	for i, desc := range t.columns {
+		for _, line := range strings.Split(desc, "\n") {
+			if columnWidths[i] < len(line) {
+				columnWidths[i] = len(desc)
+			}
+		}
+	}
+	for _, line := range lines {
+		for i, content := range line {
+			for _, l := range strings.Split(content, "\n") {
+				if columnWidths[i] < len(l) {
+					columnWidths[i] = len(l)
+				}
+			}
+		}
+	}
+
+	// calculate the total width of the table
+	totalWidth := 0
+	for _, width := range columnWidths {
+		totalWidth += width
+	}
+	totalWidth += (columns - 1) * len(t.CellSeparator)
+
+	// write header
+	if len(t.columns) > 0 {
+		err := printLine(w, t.PrintHeader, t.CellSeparator, t.columns, columnWidths)
+		if err != nil {
+			return err
+		}
+
+		// draw separation line
+		err = t.PrintSeparator(w, strings.Repeat("-", totalWidth))
+		if err != nil {
+			return err
+		}
+	}
+
+	// write all the lines
+	for i, line := range lines {
+		print := func(w io.Writer, s string) error {
+			return t.PrintData(w, i, s)
+		}
+		err := printLine(w, print, t.CellSeparator, line, columnWidths)
+		if err != nil {
+			return err
+		}
+	}
+
+	// draw separation line
+	err := t.PrintSeparator(w, strings.Repeat("-", totalWidth))
+	if err != nil {
+		return err
+	}
+
+	if len(t.footer) > 0 {
+		// write the footer
+		for _, line := range t.footer {
+			err := t.PrintFooter(w, line)
+			if err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}

internal/ui/table/table_test.go

@@ -0,0 +1,162 @@
+package table
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+)
+
+func TestTable(t *testing.T) {
+	var tests = []struct {
+		create func(t testing.TB) *Table
+		output string
+	}{
+		{
+			func(t testing.TB) *Table {
+				return New()
+			},
+			"",
+		},
+		{
+			func(t testing.TB) *Table {
+				table := New()
+				table.AddColumn("first column", "data: {{.First}}")
+				table.AddRow(struct{ First string }{"first data field"})
+				return table
+			},
+			`
+first column
+----------------------
+data: first data field
+----------------------
+`,
+		},
+		{
+			func(t testing.TB) *Table {
+				table := New()
+				table.AddColumn("  first column  ", "data: {{.First}}")
+				table.AddRow(struct{ First string }{"d"})
+				return table
+			},
+			`
+  first column
+----------------
+data: d
+----------------
+`,
+		},
+		{
+			func(t testing.TB) *Table {
+				table := New()
+				table.AddColumn("first column", "data: {{.First}}")
+				table.AddRow(struct{ First string }{"first data field"})
+				table.AddRow(struct{ First string }{"second data field"})
+				table.AddFooter("footer1")
+				table.AddFooter("footer2")
+				return table
+			},
+			`
+first column
+-----------------------
+data: first data field
+data: second data field
+-----------------------
+footer1
+footer2
+`,
+		},
+		{
+			func(t testing.TB) *Table {
+				table := New()
+				table.AddColumn("  first name", `{{printf "%12s" .FirstName}}`)
+				table.AddColumn("last name", "{{.LastName}}")
+				table.AddRow(struct{ FirstName, LastName string }{"firstname", "lastname"})
+				table.AddRow(struct{ FirstName, LastName string }{"John", "Doe"})
+				table.AddRow(struct{ FirstName, LastName string }{"Johann", "van den Berjen"})
+				return table
+			},
+			`
+  first name  last name
+----------------------------
+   firstname  lastname
+        John  Doe
+      Johann  van den Berjen
+----------------------------
+`,
+		},
+		{
+			func(t testing.TB) *Table {
+				table := New()
+				table.AddColumn("host name", `{{.Host}}`)
+				table.AddColumn("time", `{{.Time}}`)
+				table.AddColumn("zz", "xxx")
+				table.AddColumn("tags", `{{join .Tags ","}}`)
+				table.AddColumn("dirs", `{{join .Dirs ","}}`)
+
+				type data struct {
+					Host       string
+					Time       string
+					Tags, Dirs []string
+				}
+				table.AddRow(data{"foo", "2018-08-19 22:22:22", []string{"work"}, []string{"/home/user/work"}})
+				table.AddRow(data{"foo", "2018-08-19 22:22:22", []string{"other"}, []string{"/home/user/other"}})
+				table.AddRow(data{"foo", "2018-08-19 22:22:22", []string{"other"}, []string{"/home/user/other"}})
+				return table
+			},
+			`
+host name  time                 zz   tags   dirs
+------------------------------------------------------------
+foo        2018-08-19 22:22:22  xxx  work   /home/user/work
+foo        2018-08-19 22:22:22  xxx  other  /home/user/other
+foo        2018-08-19 22:22:22  xxx  other  /home/user/other
+------------------------------------------------------------
+`,
+		},
+		{
+			func(t testing.TB) *Table {
+				table := New()
+				table.AddColumn("host name", `{{.Host}}`)
+				table.AddColumn("time", `{{.Time}}`)
+				table.AddColumn("zz", "xxx")
+				table.AddColumn("tags", `{{join .Tags "\n"}}`)
+				table.AddColumn("dirs", `{{join .Dirs "\n"}}`)
+
+				type data struct {
+					Host       string
+					Time       string
+					Tags, Dirs []string
+				}
+				table.AddRow(data{"foo", "2018-08-19 22:22:22", []string{"work", "go"}, []string{"/home/user/work", "/home/user/go"}})
+				table.AddRow(data{"foo", "2018-08-19 22:22:22", []string{"other"}, []string{"/home/user/other"}})
+				table.AddRow(data{"foo", "2018-08-19 22:22:22", []string{"other", "bar"}, []string{"/home/user/other"}})
+				return table
+			},
+			`
+host name  time                 zz   tags   dirs
+------------------------------------------------------------
+foo        2018-08-19 22:22:22  xxx  work   /home/user/work
+                                     go     /home/user/go
+foo        2018-08-19 22:22:22  xxx  other  /home/user/other
+foo        2018-08-19 22:22:22  xxx  other  /home/user/other
+                                     bar
+------------------------------------------------------------
+`,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run("", func(t *testing.T) {
+			table := test.create(t)
+			buf := bytes.NewBuffer(nil)
+			err := table.Write(buf)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			want := strings.TrimLeft(test.output, "\n")
+			if string(buf.Bytes()) != want {
+				t.Errorf("wrong output\n---- want ---\n%s\n---- got ---\n%s\n-------\n", want, buf.Bytes())
+			}
+		})
+	}
+}

vendor/github.com/google/go-cmp/cmp/cmpopts/equate.go

@@ -0,0 +1,89 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+// Package cmpopts provides common options for the cmp package.
+package cmpopts
+
+import (
+	"math"
+	"reflect"
+
+	"github.com/google/go-cmp/cmp"
+)
+
+func equateAlways(_, _ interface{}) bool { return true }
+
+// EquateEmpty returns a Comparer option that determines all maps and slices
+// with a length of zero to be equal, regardless of whether they are nil.
+//
+// EquateEmpty can be used in conjunction with SortSlices and SortMaps.
+func EquateEmpty() cmp.Option {
+	return cmp.FilterValues(isEmpty, cmp.Comparer(equateAlways))
+}
+
+func isEmpty(x, y interface{}) bool {
+	vx, vy := reflect.ValueOf(x), reflect.ValueOf(y)
+	return (x != nil && y != nil && vx.Type() == vy.Type()) &&
+		(vx.Kind() == reflect.Slice || vx.Kind() == reflect.Map) &&
+		(vx.Len() == 0 && vy.Len() == 0)
+}
+
+// EquateApprox returns a Comparer option that determines float32 or float64
+// values to be equal if they are within a relative fraction or absolute margin.
+// This option is not used when either x or y is NaN or infinite.
+//
+// The fraction determines that the difference of two values must be within the
+// smaller fraction of the two values, while the margin determines that the two
+// values must be within some absolute margin.
+// To express only a fraction or only a margin, use 0 for the other parameter.
+// The fraction and margin must be non-negative.
+//
+// The mathematical expression used is equivalent to:
+//	|x-y| ≤ max(fraction*min(|x|, |y|), margin)
+//
+// EquateApprox can be used in conjunction with EquateNaNs.
+func EquateApprox(fraction, margin float64) cmp.Option {
+	if margin < 0 || fraction < 0 || math.IsNaN(margin) || math.IsNaN(fraction) {
+		panic("margin or fraction must be a non-negative number")
+	}
+	a := approximator{fraction, margin}
+	return cmp.Options{
+		cmp.FilterValues(areRealF64s, cmp.Comparer(a.compareF64)),
+		cmp.FilterValues(areRealF32s, cmp.Comparer(a.compareF32)),
+	}
+}
+
+type approximator struct{ frac, marg float64 }
+
+func areRealF64s(x, y float64) bool {
+	return !math.IsNaN(x) && !math.IsNaN(y) && !math.IsInf(x, 0) && !math.IsInf(y, 0)
+}
+func areRealF32s(x, y float32) bool {
+	return areRealF64s(float64(x), float64(y))
+}
+func (a approximator) compareF64(x, y float64) bool {
+	relMarg := a.frac * math.Min(math.Abs(x), math.Abs(y))
+	return math.Abs(x-y) <= math.Max(a.marg, relMarg)
+}
+func (a approximator) compareF32(x, y float32) bool {
+	return a.compareF64(float64(x), float64(y))
+}
+
+// EquateNaNs returns a Comparer option that determines float32 and float64
+// NaN values to be equal.
+//
+// EquateNaNs can be used in conjunction with EquateApprox.
+func EquateNaNs() cmp.Option {
+	return cmp.Options{
+		cmp.FilterValues(areNaNsF64s, cmp.Comparer(equateAlways)),
+		cmp.FilterValues(areNaNsF32s, cmp.Comparer(equateAlways)),
+	}
+}
+
+func areNaNsF64s(x, y float64) bool {
+	return math.IsNaN(x) && math.IsNaN(y)
+}
+func areNaNsF32s(x, y float32) bool {
+	return areNaNsF64s(float64(x), float64(y))
+}

vendor/github.com/google/go-cmp/cmp/cmpopts/ignore.go

@@ -0,0 +1,145 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+package cmpopts
+
+import (
+	"fmt"
+	"reflect"
+	"unicode"
+	"unicode/utf8"
+
+	"github.com/google/go-cmp/cmp"
+)
+
+// IgnoreFields returns an Option that ignores exported fields of the
+// given names on a single struct type.
+// The struct type is specified by passing in a value of that type.
+//
+// The name may be a dot-delimited string (e.g., "Foo.Bar") to ignore a
+// specific sub-field that is embedded or nested within the parent struct.
+//
+// This does not handle unexported fields; use IgnoreUnexported instead.
+func IgnoreFields(typ interface{}, names ...string) cmp.Option {
+	sf := newStructFilter(typ, names...)
+	return cmp.FilterPath(sf.filter, cmp.Ignore())
+}
+
+// IgnoreTypes returns an Option that ignores all values assignable to
+// certain types, which are specified by passing in a value of each type.
+func IgnoreTypes(typs ...interface{}) cmp.Option {
+	tf := newTypeFilter(typs...)
+	return cmp.FilterPath(tf.filter, cmp.Ignore())
+}
+
+type typeFilter []reflect.Type
+
+func newTypeFilter(typs ...interface{}) (tf typeFilter) {
+	for _, typ := range typs {
+		t := reflect.TypeOf(typ)
+		if t == nil {
+			// This occurs if someone tries to pass in sync.Locker(nil)
+			panic("cannot determine type; consider using IgnoreInterfaces")
+		}
+		tf = append(tf, t)
+	}
+	return tf
+}
+func (tf typeFilter) filter(p cmp.Path) bool {
+	if len(p) < 1 {
+		return false
+	}
+	t := p.Last().Type()
+	for _, ti := range tf {
+		if t.AssignableTo(ti) {
+			return true
+		}
+	}
+	return false
+}
+
+// IgnoreInterfaces returns an Option that ignores all values or references of
+// values assignable to certain interface types. These interfaces are specified
+// by passing in an anonymous struct with the interface types embedded in it.
+// For example, to ignore sync.Locker, pass in struct{sync.Locker}{}.
+func IgnoreInterfaces(ifaces interface{}) cmp.Option {
+	tf := newIfaceFilter(ifaces)
+	return cmp.FilterPath(tf.filter, cmp.Ignore())
+}
+
+type ifaceFilter []reflect.Type
+
+func newIfaceFilter(ifaces interface{}) (tf ifaceFilter) {
+	t := reflect.TypeOf(ifaces)
+	if ifaces == nil || t.Name() != "" || t.Kind() != reflect.Struct {
+		panic("input must be an anonymous struct")
+	}
+	for i := 0; i < t.NumField(); i++ {
+		fi := t.Field(i)
+		switch {
+		case !fi.Anonymous:
+			panic("struct cannot have named fields")
+		case fi.Type.Kind() != reflect.Interface:
+			panic("embedded field must be an interface type")
+		case fi.Type.NumMethod() == 0:
+			// This matches everything; why would you ever want this?
+			panic("cannot ignore empty interface")
+		default:
+			tf = append(tf, fi.Type)
+		}
+	}
+	return tf
+}
+func (tf ifaceFilter) filter(p cmp.Path) bool {
+	if len(p) < 1 {
+		return false
+	}
+	t := p.Last().Type()
+	for _, ti := range tf {
+		if t.AssignableTo(ti) {
+			return true
+		}
+		if t.Kind() != reflect.Ptr && reflect.PtrTo(t).AssignableTo(ti) {
+			return true
+		}
+	}
+	return false
+}
+
+// IgnoreUnexported returns an Option that only ignores the immediate unexported
+// fields of a struct, including anonymous fields of unexported types.
+// In particular, unexported fields within the struct's exported fields
+// of struct types, including anonymous fields, will not be ignored unless the
+// type of the field itself is also passed to IgnoreUnexported.
+func IgnoreUnexported(typs ...interface{}) cmp.Option {
+	ux := newUnexportedFilter(typs...)
+	return cmp.FilterPath(ux.filter, cmp.Ignore())
+}
+
+type unexportedFilter struct{ m map[reflect.Type]bool }
+
+func newUnexportedFilter(typs ...interface{}) unexportedFilter {
+	ux := unexportedFilter{m: make(map[reflect.Type]bool)}
+	for _, typ := range typs {
+		t := reflect.TypeOf(typ)
+		if t == nil || t.Kind() != reflect.Struct {
+			panic(fmt.Sprintf("invalid struct type: %T", typ))
+		}
+		ux.m[t] = true
+	}
+	return ux
+}
+func (xf unexportedFilter) filter(p cmp.Path) bool {
+	sf, ok := p.Index(-1).(cmp.StructField)
+	if !ok {
+		return false
+	}
+	return xf.m[p.Index(-2).Type()] && !isExported(sf.Name())
+}
+
+// isExported reports whether the identifier is exported.
+func isExported(id string) bool {
+	r, _ := utf8.DecodeRuneInString(id)
+	return unicode.IsUpper(r)
+}

vendor/github.com/google/go-cmp/cmp/cmpopts/sort.go

@@ -0,0 +1,146 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+package cmpopts
+
+import (
+	"fmt"
+	"reflect"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/google/go-cmp/cmp/internal/function"
+)
+
+// SortSlices returns a Transformer option that sorts all []V.
+// The less function must be of the form "func(T, T) bool" which is used to
+// sort any slice with element type V that is assignable to T.
+//
+// The less function must be:
+//	• Deterministic: less(x, y) == less(x, y)
+//	• Irreflexive: !less(x, x)
+//	• Transitive: if !less(x, y) and !less(y, z), then !less(x, z)
+//
+// The less function does not have to be "total". That is, if !less(x, y) and
+// !less(y, x) for two elements x and y, their relative order is maintained.
+//
+// SortSlices can be used in conjunction with EquateEmpty.
+func SortSlices(less interface{}) cmp.Option {
+	vf := reflect.ValueOf(less)
+	if !function.IsType(vf.Type(), function.Less) || vf.IsNil() {
+		panic(fmt.Sprintf("invalid less function: %T", less))
+	}
+	ss := sliceSorter{vf.Type().In(0), vf}
+	return cmp.FilterValues(ss.filter, cmp.Transformer("Sort", ss.sort))
+}
+
+type sliceSorter struct {
+	in  reflect.Type  // T
+	fnc reflect.Value // func(T, T) bool
+}
+
+func (ss sliceSorter) filter(x, y interface{}) bool {
+	vx, vy := reflect.ValueOf(x), reflect.ValueOf(y)
+	if !(x != nil && y != nil && vx.Type() == vy.Type()) ||
+		!(vx.Kind() == reflect.Slice && vx.Type().Elem().AssignableTo(ss.in)) ||
+		(vx.Len() <= 1 && vy.Len() <= 1) {
+		return false
+	}
+	// Check whether the slices are already sorted to avoid an infinite
+	// recursion cycle applying the same transform to itself.
+	ok1 := sliceIsSorted(x, func(i, j int) bool { return ss.less(vx, i, j) })
+	ok2 := sliceIsSorted(y, func(i, j int) bool { return ss.less(vy, i, j) })
+	return !ok1 || !ok2
+}
+func (ss sliceSorter) sort(x interface{}) interface{} {
+	src := reflect.ValueOf(x)
+	dst := reflect.MakeSlice(src.Type(), src.Len(), src.Len())
+	for i := 0; i < src.Len(); i++ {
+		dst.Index(i).Set(src.Index(i))
+	}
+	sortSliceStable(dst.Interface(), func(i, j int) bool { return ss.less(dst, i, j) })
+	ss.checkSort(dst)
+	return dst.Interface()
+}
+func (ss sliceSorter) checkSort(v reflect.Value) {
+	start := -1 // Start of a sequence of equal elements.
+	for i := 1; i < v.Len(); i++ {
+		if ss.less(v, i-1, i) {
+			// Check that first and last elements in v[start:i] are equal.
+			if start >= 0 && (ss.less(v, start, i-1) || ss.less(v, i-1, start)) {
+				panic(fmt.Sprintf("incomparable values detected: want equal elements: %v", v.Slice(start, i)))
+			}
+			start = -1
+		} else if start == -1 {
+			start = i
+		}
+	}
+}
+func (ss sliceSorter) less(v reflect.Value, i, j int) bool {
+	vx, vy := v.Index(i), v.Index(j)
+	return ss.fnc.Call([]reflect.Value{vx, vy})[0].Bool()
+}
+
+// SortMaps returns a Transformer option that flattens map[K]V types to be a
+// sorted []struct{K, V}. The less function must be of the form
+// "func(T, T) bool" which is used to sort any map with key K that is
+// assignable to T.
+//
+// Flattening the map into a slice has the property that cmp.Equal is able to
+// use Comparers on K or the K.Equal method if it exists.
+//
+// The less function must be:
+//	• Deterministic: less(x, y) == less(x, y)
+//	• Irreflexive: !less(x, x)
+//	• Transitive: if !less(x, y) and !less(y, z), then !less(x, z)
+//	• Total: if x != y, then either less(x, y) or less(y, x)
+//
+// SortMaps can be used in conjunction with EquateEmpty.
+func SortMaps(less interface{}) cmp.Option {
+	vf := reflect.ValueOf(less)
+	if !function.IsType(vf.Type(), function.Less) || vf.IsNil() {
+		panic(fmt.Sprintf("invalid less function: %T", less))
+	}
+	ms := mapSorter{vf.Type().In(0), vf}
+	return cmp.FilterValues(ms.filter, cmp.Transformer("Sort", ms.sort))
+}
+
+type mapSorter struct {
+	in  reflect.Type  // T
+	fnc reflect.Value // func(T, T) bool
+}
+
+func (ms mapSorter) filter(x, y interface{}) bool {
+	vx, vy := reflect.ValueOf(x), reflect.ValueOf(y)
+	return (x != nil && y != nil && vx.Type() == vy.Type()) &&
+		(vx.Kind() == reflect.Map && vx.Type().Key().AssignableTo(ms.in)) &&
+		(vx.Len() != 0 || vy.Len() != 0)
+}
+func (ms mapSorter) sort(x interface{}) interface{} {
+	src := reflect.ValueOf(x)
+	outType := mapEntryType(src.Type())
+	dst := reflect.MakeSlice(reflect.SliceOf(outType), src.Len(), src.Len())
+	for i, k := range src.MapKeys() {
+		v := reflect.New(outType).Elem()
+		v.Field(0).Set(k)
+		v.Field(1).Set(src.MapIndex(k))
+		dst.Index(i).Set(v)
+	}
+	sortSlice(dst.Interface(), func(i, j int) bool { return ms.less(dst, i, j) })
+	ms.checkSort(dst)
+	return dst.Interface()
+}
+func (ms mapSorter) checkSort(v reflect.Value) {
+	for i := 1; i < v.Len(); i++ {
+		if !ms.less(v, i-1, i) {
+			panic(fmt.Sprintf("partial order detected: want %v < %v", v.Index(i-1), v.Index(i)))
+		}
+	}
+}
+func (ms mapSorter) less(v reflect.Value, i, j int) bool {
+	vx, vy := v.Index(i).Field(0), v.Index(j).Field(0)
+	if !hasReflectStructOf {
+		vx, vy = vx.Elem(), vy.Elem()
+	}
+	return ms.fnc.Call([]reflect.Value{vx, vy})[0].Bool()
+}

vendor/github.com/google/go-cmp/cmp/cmpopts/sort_go17.go

@@ -0,0 +1,46 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+// +build !go1.8
+
+package cmpopts
+
+import (
+	"reflect"
+	"sort"
+)
+
+const hasReflectStructOf = false
+
+func mapEntryType(reflect.Type) reflect.Type {
+	return reflect.TypeOf(struct{ K, V interface{} }{})
+}
+
+func sliceIsSorted(slice interface{}, less func(i, j int) bool) bool {
+	return sort.IsSorted(reflectSliceSorter{reflect.ValueOf(slice), less})
+}
+func sortSlice(slice interface{}, less func(i, j int) bool) {
+	sort.Sort(reflectSliceSorter{reflect.ValueOf(slice), less})
+}
+func sortSliceStable(slice interface{}, less func(i, j int) bool) {
+	sort.Stable(reflectSliceSorter{reflect.ValueOf(slice), less})
+}
+
+type reflectSliceSorter struct {
+	slice reflect.Value
+	less  func(i, j int) bool
+}
+
+func (ss reflectSliceSorter) Len() int {
+	return ss.slice.Len()
+}
+func (ss reflectSliceSorter) Less(i, j int) bool {
+	return ss.less(i, j)
+}
+func (ss reflectSliceSorter) Swap(i, j int) {
+	vi := ss.slice.Index(i).Interface()
+	vj := ss.slice.Index(j).Interface()
+	ss.slice.Index(i).Set(reflect.ValueOf(vj))
+	ss.slice.Index(j).Set(reflect.ValueOf(vi))
+}

vendor/github.com/google/go-cmp/cmp/cmpopts/sort_go18.go

@@ -0,0 +1,31 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+// +build go1.8
+
+package cmpopts
+
+import (
+	"reflect"
+	"sort"
+)
+
+const hasReflectStructOf = true
+
+func mapEntryType(t reflect.Type) reflect.Type {
+	return reflect.StructOf([]reflect.StructField{
+		{Name: "K", Type: t.Key()},
+		{Name: "V", Type: t.Elem()},
+	})
+}
+
+func sliceIsSorted(slice interface{}, less func(i, j int) bool) bool {
+	return sort.SliceIsSorted(slice, less)
+}
+func sortSlice(slice interface{}, less func(i, j int) bool) {
+	sort.Slice(slice, less)
+}
+func sortSliceStable(slice interface{}, less func(i, j int) bool) {
+	sort.SliceStable(slice, less)
+}

vendor/github.com/google/go-cmp/cmp/cmpopts/struct_filter.go

@@ -0,0 +1,182 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE.md file.
+
+package cmpopts
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+
+	"github.com/google/go-cmp/cmp"
+)
+
+// filterField returns a new Option where opt is only evaluated on paths that
+// include a specific exported field on a single struct type.
+// The struct type is specified by passing in a value of that type.
+//
+// The name may be a dot-delimited string (e.g., "Foo.Bar") to select a
+// specific sub-field that is embedded or nested within the parent struct.
+func filterField(typ interface{}, name string, opt cmp.Option) cmp.Option {
+	// TODO: This is currently unexported over concerns of how helper filters
+	// can be composed together easily.
+	// TODO: Add tests for FilterField.
+
+	sf := newStructFilter(typ, name)
+	return cmp.FilterPath(sf.filter, opt)
+}
+
+type structFilter struct {
+	t  reflect.Type // The root struct type to match on
+	ft fieldTree    // Tree of fields to match on
+}
+
+func newStructFilter(typ interface{}, names ...string) structFilter {
+	// TODO: Perhaps allow * as a special identifier to allow ignoring any
+	// number of path steps until the next field match?
+	// This could be useful when a concrete struct gets transformed into
+	// an anonymous struct where it is not possible to specify that by type,
+	// but the transformer happens to provide guarantees about the names of
+	// the transformed fields.
+
+	t := reflect.TypeOf(typ)
+	if t == nil || t.Kind() != reflect.Struct {
+		panic(fmt.Sprintf("%T must be a struct", typ))
+	}
+	var ft fieldTree
+	for _, name := range names {
+		cname, err := canonicalName(t, name)
+		if err != nil {
+			panic(fmt.Sprintf("%s: %v", strings.Join(cname, "."), err))
+		}
+		ft.insert(cname)
+	}
+	return structFilter{t, ft}
+}
+
+func (sf structFilter) filter(p cmp.Path) bool {
+	for i, ps := range p {
+		if ps.Type().AssignableTo(sf.t) && sf.ft.matchPrefix(p[i+1:]) {
+			return true
+		}
+	}
+	return false
+}
+
+// fieldTree represents a set of dot-separated identifiers.
+//
+// For example, inserting the following selectors:
+//	Foo
+//	Foo.Bar.Baz
+//	Foo.Buzz
+//	Nuka.Cola.Quantum
+//
+// Results in a tree of the form:
+//	{sub: {
+//		"Foo": {ok: true, sub: {
+//			"Bar": {sub: {
+//				"Baz": {ok: true},
+//			}},
+//			"Buzz": {ok: true},
+//		}},
+//		"Nuka": {sub: {
+//			"Cola": {sub: {
+//				"Quantum": {ok: true},
+//			}},
+//		}},
+//	}}
+type fieldTree struct {
+	ok  bool                 // Whether this is a specified node
+	sub map[string]fieldTree // The sub-tree of fields under this node
+}
+
+// insert inserts a sequence of field accesses into the tree.
+func (ft *fieldTree) insert(cname []string) {
+	if ft.sub == nil {
+		ft.sub = make(map[string]fieldTree)
+	}
+	if len(cname) == 0 {
+		ft.ok = true
+		return
+	}
+	sub := ft.sub[cname[0]]
+	sub.insert(cname[1:])
+	ft.sub[cname[0]] = sub
+}
+
+// matchPrefix reports whether any selector in the fieldTree matches
+// the start of path p.
+func (ft fieldTree) matchPrefix(p cmp.Path) bool {
+	for _, ps := range p {
+		switch ps := ps.(type) {
+		case cmp.StructField:
+			ft = ft.sub[ps.Name()]
+			if ft.ok {
+				return true
+			}
+			if len(ft.sub) == 0 {
+				return false
+			}
+		case cmp.Indirect:
+		default:
+			return false
+		}
+	}
+	return false
+}
+
+// canonicalName returns a list of identifiers where any struct field access
+// through an embedded field is expanded to include the names of the embedded
+// types themselves.
+//
+// For example, suppose field "Foo" is not directly in the parent struct,
+// but actually from an embedded struct of type "Bar". Then, the canonical name
+// of "Foo" is actually "Bar.Foo".
+//
+// Suppose field "Foo" is not directly in the parent struct, but actually
+// a field in two different embedded structs of types "Bar" and "Baz".
+// Then the selector "Foo" causes a panic since it is ambiguous which one it
+// refers to. The user must specify either "Bar.Foo" or "Baz.Foo".
+func canonicalName(t reflect.Type, sel string) ([]string, error) {
+	var name string
+	sel = strings.TrimPrefix(sel, ".")
+	if sel == "" {
+		return nil, fmt.Errorf("name must not be empty")
+	}
+	if i := strings.IndexByte(sel, '.'); i < 0 {
+		name, sel = sel, ""
+	} else {
+		name, sel = sel[:i], sel[i:]
+	}
+
+	// Type must be a struct or pointer to struct.
+	if t.Kind() == reflect.Ptr {
+		t = t.Elem()
+	}
+	if t.Kind() != reflect.Struct {
+		return nil, fmt.Errorf("%v must be a struct", t)
+	}
+
+	// Find the canonical name for this current field name.
+	// If the field exists in an embedded struct, then it will be expanded.
+	if !isExported(name) {
+		// Disallow unexported fields:
+		//	* To discourage people from actually touching unexported fields
+		//	* FieldByName is buggy (https://golang.org/issue/4876)
+		return []string{name}, fmt.Errorf("name must be exported")
+	}
+	sf, ok := t.FieldByName(name)
+	if !ok {
+		return []string{name}, fmt.Errorf("does not exist")
+	}
+	var ss []string
+	for i := range sf.Index {
+		ss = append(ss, t.FieldByIndex(sf.Index[:i+1]).Name)
+	}
+	if sel == "" {
+		return ss, nil
+	}
+	ssPost, err := canonicalName(sf.Type, sel)
+	return append(ss, ssPost...), err
+}