From 6156f906011644391a6b4e21061bc9be1fbb01c6 Mon Sep 17 00:00:00 2001
From: Zach Kipp <kipp.zach@gmail.com>
Date: Sun, 6 Sep 2020 16:50:16 -0700
Subject: [PATCH] Fix test failure in different local time zones

TestParseDuration relied on an elapsed time calculation which
would vary based on the system local time. Fix the test by not relying
on the system time location. Also make the test more deterministic
by injecting time in tests rather than using system time.

Fixes #4529.
---
 fs/parseduration.go      | 12 +++++++++---
 fs/parseduration_test.go | 22 ++++++++++++++++------
 2 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/fs/parseduration.go b/fs/parseduration.go
index cd3f192ac..b5104cc6c 100644
--- a/fs/parseduration.go
+++ b/fs/parseduration.go
@@ -88,8 +88,9 @@ func parseDurationDates(age string, epoch time.Time) (t time.Duration, err error
 	return t, err
 }
 
-// ParseDuration parses a duration string. Accept ms|s|m|h|d|w|M|y suffixes. Defaults to second if not provided
-func ParseDuration(age string) (d time.Duration, err error) {
+// parseDurationFromNow parses a duration string. Allows ParseDuration to match the time
+// package and easier testing within the fs package.
+func parseDurationFromNow(age string, getNow func() time.Time) (d time.Duration, err error) {
 	if age == "off" {
 		return time.Duration(DurationOff), nil
 	}
@@ -105,7 +106,7 @@ func ParseDuration(age string) (d time.Duration, err error) {
 		return d, nil
 	}
 
-	d, err = parseDurationDates(age, time.Now())
+	d, err = parseDurationDates(age, getNow())
 	if err == nil {
 		return d, nil
 	}
@@ -113,6 +114,11 @@ func ParseDuration(age string) (d time.Duration, err error) {
 	return d, err
 }
 
+// ParseDuration parses a duration string. Accept ms|s|m|h|d|w|M|y suffixes. Defaults to second if not provided
+func ParseDuration(age string) (time.Duration, error) {
+	return parseDurationFromNow(age, time.Now)
+}
+
 // ReadableString parses d into a human readable duration.
 // Based on https://github.com/hako/durafmt
 func (d Duration) ReadableString() string {
diff --git a/fs/parseduration_test.go b/fs/parseduration_test.go
index 04830ef06..69de520ca 100644
--- a/fs/parseduration_test.go
+++ b/fs/parseduration_test.go
@@ -15,6 +15,11 @@ import (
 var _ pflag.Value = (*Duration)(nil)
 
 func TestParseDuration(t *testing.T) {
+	now := time.Date(2020, 9, 5, 8, 15, 5, 250, time.UTC)
+	getNow := func() time.Time {
+		return now
+	}
+
 	for _, test := range []struct {
 		in   string
 		want time.Duration
@@ -37,12 +42,12 @@ func TestParseDuration(t *testing.T) {
 		{"1x", 0, true},
 		{"off", time.Duration(DurationOff), false},
 		{"1h2m3s", time.Hour + 2*time.Minute + 3*time.Second, false},
-		{"2001-02-03", time.Since(time.Date(2001, 2, 3, 0, 0, 0, 0, time.UTC)), false},
-		{"2001-02-03 10:11:12", time.Since(time.Date(2001, 2, 3, 10, 11, 12, 0, time.UTC)), false},
-		{"2001-02-03T10:11:12", time.Since(time.Date(2001, 2, 3, 10, 11, 12, 0, time.UTC)), false},
-		{"2001-02-03T10:11:12.123Z", time.Since(time.Date(2001, 2, 3, 10, 11, 12, 123, time.UTC)), false},
+		{"2001-02-03", now.Sub(time.Date(2001, 2, 3, 0, 0, 0, 0, time.UTC)), false},
+		{"2001-02-03 10:11:12", now.Sub(time.Date(2001, 2, 3, 10, 11, 12, 0, time.UTC)), false},
+		{"2001-02-03T10:11:12", now.Sub(time.Date(2001, 2, 3, 10, 11, 12, 0, time.UTC)), false},
+		{"2001-02-03T10:11:12.123Z", now.Sub(time.Date(2001, 2, 3, 10, 11, 12, 123, time.UTC)), false},
 	} {
-		duration, err := ParseDuration(test.in)
+		duration, err := parseDurationFromNow(test.in, getNow)
 		if test.err {
 			require.Error(t, err)
 		} else {
@@ -58,6 +63,11 @@ func TestParseDuration(t *testing.T) {
 }
 
 func TestDurationString(t *testing.T) {
+	now := time.Date(2020, 9, 5, 8, 15, 5, 250, time.UTC)
+	getNow := func() time.Time {
+		return now
+	}
+
 	for _, test := range []struct {
 		in   time.Duration
 		want string
@@ -88,7 +98,7 @@ func TestDurationString(t *testing.T) {
 		got := Duration(test.in).String()
 		assert.Equal(t, test.want, got)
 		// Test the reverse
-		reverse, err := ParseDuration(test.want)
+		reverse, err := parseDurationFromNow(test.want, getNow)
 		assert.NoError(t, err)
 		assert.Equal(t, test.in, reverse)
 	}