fix: enable dyff rename detection when --find-renames is set (#980)

* fix: enable dyff rename detection when --find-renames is set

The condition guarding dyff.DetectRenames(true) was inverted: it
enabled rename detection only when FindRenames was NOT set (<= 0) and
disabled it when the user explicitly requested it via --find-renames.

Flip the condition from <= 0 to > 0 so that dyff's rename detection
is enabled when --find-renames is set to any positive value, matching
the documented behavior.

Fixes #976

Signed-off-by: yxxhero <aiopsclub@163.com>

* fix: propagate FindRenames to Report and update tests

Pass FindRenames from Options to Report so that printDyffReport can
use it to conditionally enable dyff.DetectRenames. Update test name
and add FindRenames field to test reports for consistency.

Signed-off-by: yxxhero <aiopsclub@163.com>

* fix: preserve FindRenames in doSuppress and add regression test

Copy FindRenames into the filtered report in doSuppress so that
--find-renames still works when --suppress-output-line-regex is used.
Add TestPrintDyffReportFindRenamesChangesOutput to verify that dyff
output differs between FindRenames == 0 and FindRenames > 0.

Signed-off-by: yxxhero <aiopsclub@163.com>

* refactor: make Report.findRenames unexported and improve tests

Make findRenames an unexported field on Report since it is internal
state for dyff printing, not part of the public API.

Rename TestPrintDyffReportDoesNotMergeAddRemoveWithFindRenames to
TestPrintDyffReportAddRemoveDiffersFromModify for clarity.

Replace the brittle NotEqual assertion in the rename detection test
with specific assertions on stable dyff output markers (presence of
'one document removed/added' vs 'value change') to reliably verify
that rename detection is toggled by findRenames.

Signed-off-by: yxxhero <aiopsclub@163.com>

---------

Signed-off-by: yxxhero <aiopsclub@163.com>

Author: yxxhero

diff/diff.go

@@ -65,7 +65,7 @@ func ManifestReport(oldIndex, newIndex map[string]*manifest.MappingResult, optio
 }
 
 func generateReport(oldIndex, newIndex map[string]*manifest.MappingResult, newOwnedReleases map[string]OwnershipDiff, options *Options) (bool, *Report, error) {
-	report := Report{}
+	report := Report{findRenames: options.FindRenames}
 	report.setupReportFormat(options.OutputFormat)
 	var possiblyRemoved []string
 
@@ -118,7 +118,9 @@ func doSuppress(report Report, suppressedOutputLineRegex []string) (Report, erro
 		return report, nil
 	}
 
-	filteredReport := Report{}
+	filteredReport := Report{
+		findRenames: report.findRenames,
+	}
 	filteredReport.format = report.format
 	filteredReport.Entries = []ReportEntry{}
 

diff/report.go

@@ -20,9 +20,10 @@ import (
 
 // Report to store report data and format
 type Report struct {
-	format  ReportFormat
-	Entries []ReportEntry
-	mode    string
+	format      ReportFormat
+	Entries     []ReportEntry
+	mode        string
+	findRenames float32
 }
 
 // ReportEntry to store changes between releases
@@ -115,6 +116,9 @@ func printDyffReport(r *Report, to io.Writer) {
 		dyff.IgnoreWhitespaceChanges(true),
 		dyff.KubernetesEntityDetection(true),
 	)
+	if r.findRenames > 0 {
+		compareOptions = append(compareOptions, dyff.DetectRenames(true))
+	}
 	report, _ := dyff.CompareInputFiles(currentInputFile, newInputFile, compareOptions...)
 	reportWriter := &dyff.HumanReport{
 		Report:               report,

diff/report_test.go

@@ -104,8 +104,9 @@ func TestPrintDyffReportWithAddAndRemove(t *testing.T) {
 	require.Contains(t, output, "new-app", "Expected dyff output to show added resource new-app")
 }
 
-func TestPrintDyffReportDoesNotMergeAddRemove(t *testing.T) {
+func TestPrintDyffReportAddRemoveDiffersFromModify(t *testing.T) {
 	addRemoveReport := &Report{
+		findRenames: 1.0,
 		Entries: []ReportEntry{
 			{
 				Key:        "default, old-app, Deployment (apps)",
@@ -133,6 +134,7 @@ func TestPrintDyffReportDoesNotMergeAddRemove(t *testing.T) {
 	}
 
 	modifyReport := &Report{
+		findRenames: 1.0,
 		Entries: []ReportEntry{
 			{
 				Key:        "default, app, Deployment (apps)",
@@ -164,6 +166,55 @@ func TestPrintDyffReportDoesNotMergeAddRemove(t *testing.T) {
 	require.Contains(t, addRemoveOutput, "new-app")
 }
 
+func TestPrintDyffReportRenameDetectionEnabledWithFindRenames(t *testing.T) {
+	entries := []ReportEntry{
+		{
+			Key:        "default, old-app, Deployment (apps)",
+			Kind:       "Deployment",
+			ChangeType: "REMOVE",
+			Diffs: []difflib.DiffRecord{
+				{Payload: "apiVersion: apps/v1", Delta: difflib.LeftOnly},
+				{Payload: "kind: Deployment", Delta: difflib.LeftOnly},
+				{Payload: "metadata:", Delta: difflib.LeftOnly},
+				{Payload: "  name: old-app", Delta: difflib.LeftOnly},
+				{Payload: "spec:", Delta: difflib.LeftOnly},
+				{Payload: "  replicas: 3", Delta: difflib.LeftOnly},
+			},
+		},
+		{
+			Key:        "default, new-app, Deployment (apps)",
+			Kind:       "Deployment",
+			ChangeType: "ADD",
+			Diffs: []difflib.DiffRecord{
+				{Payload: "apiVersion: apps/v1", Delta: difflib.RightOnly},
+				{Payload: "kind: Deployment", Delta: difflib.RightOnly},
+				{Payload: "metadata:", Delta: difflib.RightOnly},
+				{Payload: "  name: new-app", Delta: difflib.RightOnly},
+				{Payload: "spec:", Delta: difflib.RightOnly},
+				{Payload: "  replicas: 3", Delta: difflib.RightOnly},
+			},
+		},
+	}
+
+	var noRenameBuf bytes.Buffer
+	printDyffReport(&Report{findRenames: 0, Entries: entries}, &noRenameBuf)
+	noRenameOutput := noRenameBuf.String()
+
+	require.Contains(t, noRenameOutput, "one document removed",
+		"Without findRenames, dyff should report a separate document removal")
+	require.Contains(t, noRenameOutput, "one document added",
+		"Without findRenames, dyff should report a separate document addition")
+
+	var withRenameBuf bytes.Buffer
+	printDyffReport(&Report{findRenames: 1.0, Entries: entries}, &withRenameBuf)
+	withRenameOutput := withRenameBuf.String()
+
+	require.NotContains(t, withRenameOutput, "one document removed",
+		"With findRenames > 0, dyff should match documents as a rename, not report removal")
+	require.Contains(t, withRenameOutput, "value change",
+		"With findRenames > 0, dyff should show the matched rename as a value change")
+}
+
 func TestPrintDyffReportEmpty(t *testing.T) {
 	report := &Report{
 		Entries: []ReportEntry{},