From b69c6408a6cec3700915469c285c279a4356e9dc Mon Sep 17 00:00:00 2001
From: Srigovind Nayak <sgovind.dev@outlook.com>
Date: Sat, 7 Sep 2024 15:00:21 +0530
Subject: [PATCH] forget: make oldest snapshot marker more strict

Now, a snapshot is only marked as oldest if it's the last in the list AND its values matches the last seen value for that bucket.

Also, updated the corresponding golden files for the tests.
---
 internal/restic/snapshot_policy.go                | 10 +++++-----
 internal/restic/testdata/policy_keep_snapshots_36 |  2 +-
 internal/restic/testdata/policy_keep_snapshots_37 |  4 ++--
 internal/restic/testdata/policy_keep_snapshots_38 |  2 +-
 internal/restic/testdata/policy_keep_snapshots_4  |  2 +-
 5 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/internal/restic/snapshot_policy.go b/internal/restic/snapshot_policy.go
index f5c90d6e4..28f871f4a 100644
--- a/internal/restic/snapshot_policy.go
+++ b/internal/restic/snapshot_policy.go
@@ -256,13 +256,13 @@ func ApplyPolicy(list Snapshots, p ExpirePolicy) (keep, remove Snapshots, reason
 				if val != b.Last || nr == len(list)-1 {
 					debug.Log("keep %v %v, bucker %v, val %v\n", cur.Time, cur.id.Str(), i, val)
 					keepSnap = true
+					if val == b.Last && nr == len(list)-1 {
+						b.reason = fmt.Sprintf("oldest %v", b.reason)
+					}
 					buckets[i].Last = val
 					if buckets[i].Count > 0 {
 						buckets[i].Count--
 					}
-					if nr == len(list)-1 {
-						b.reason = fmt.Sprintf("oldest %v", b.reason)
-					}
 					keepSnapReasons = append(keepSnapReasons, b.reason)
 				}
 			}
@@ -278,10 +278,10 @@ func ApplyPolicy(list Snapshots, p ExpirePolicy) (keep, remove Snapshots, reason
 					if val != b.Last || nr == len(list)-1 {
 						debug.Log("keep %v, time %v, ID %v, bucker %v, val %v %v\n", b.reason, cur.Time, cur.id.Str(), i, val, b.Last)
 						keepSnap = true
-						bucketsWithin[i].Last = val
-						if nr == len(list)-1 {
+						if val == b.Last && nr == len(list)-1 {
 							b.reason = fmt.Sprintf("oldest %v", b.reason)
 						}
+						bucketsWithin[i].Last = val
 						keepSnapReasons = append(keepSnapReasons, fmt.Sprintf("%v %v", b.reason, b.Within))
 					}
 				}
diff --git a/internal/restic/testdata/policy_keep_snapshots_36 b/internal/restic/testdata/policy_keep_snapshots_36
index 6023e993e..cce4cf537 100644
--- a/internal/restic/testdata/policy_keep_snapshots_36
+++ b/internal/restic/testdata/policy_keep_snapshots_36
@@ -1978,7 +1978,7 @@
         "paths": null
       },
       "matches": [
-        "oldest last snapshot"
+        "last snapshot"
       ],
       "counters": {
         "last": -1
diff --git a/internal/restic/testdata/policy_keep_snapshots_37 b/internal/restic/testdata/policy_keep_snapshots_37
index 0cf643ab6..9856a83d6 100644
--- a/internal/restic/testdata/policy_keep_snapshots_37
+++ b/internal/restic/testdata/policy_keep_snapshots_37
@@ -2169,8 +2169,8 @@
         "paths": null
       },
       "matches": [
-        "oldest last snapshot",
-        "oldest hourly snapshot"
+        "last snapshot",
+        "hourly snapshot"
       ],
       "counters": {
         "last": -1,
diff --git a/internal/restic/testdata/policy_keep_snapshots_38 b/internal/restic/testdata/policy_keep_snapshots_38
index ef4eb6777..f5d7136d4 100644
--- a/internal/restic/testdata/policy_keep_snapshots_38
+++ b/internal/restic/testdata/policy_keep_snapshots_38
@@ -1708,7 +1708,7 @@
         "paths": null
       },
       "matches": [
-        "oldest hourly snapshot"
+        "hourly snapshot"
       ],
       "counters": {
         "hourly": -1
diff --git a/internal/restic/testdata/policy_keep_snapshots_4 b/internal/restic/testdata/policy_keep_snapshots_4
index 66e5cebe2..ff572d6a0 100644
--- a/internal/restic/testdata/policy_keep_snapshots_4
+++ b/internal/restic/testdata/policy_keep_snapshots_4
@@ -1978,7 +1978,7 @@
         "paths": null
       },
       "matches": [
-        "oldest last snapshot"
+        "last snapshot"
       ],
       "counters": {
         "last": 97