refactor: improve error handling in structured entry creation and update tests

Author: madhunzv

diff/diff.go

@@ -4,8 +4,8 @@ import (
 	"bytes"
 	"fmt"
 	"io"
-	"log"
 	"math"
+	"os"
 	"regexp"
 	"sort"
 	"strings"
@@ -278,14 +278,16 @@ func doDiff(report *Report, key string, oldContent *manifest.MappingResult, newC
 	if options.StructuredOutput() {
 		entry, err := buildStructuredEntry(key, changeType, subjectKind, options.SuppressedKinds, oldContent, newContent)
 		if err != nil {
-			// Log error with context before panicking to aid debugging
-			log.Printf("Error building structured entry for %s (kind: %s, changeType: %s): %v", key, subjectKind, changeType, err)
-			panic(fmt.Errorf("failed to build structured entry: %w", err))
-		}
-		if changeType == "MODIFY" && !entry.ChangesSuppressed && len(entry.Changes) == 0 {
-			return
+			// Log warning and omit field-level changes for this entry
+			// printStructuredReport() will still output a basic entry with name and changeType
+			fmt.Fprintf(os.Stderr, "Warning: failed to build structured entry for %s (kind: %s, changeType: %s): %v\n",
+				key, subjectKind, changeType, err)
+		} else {
+			if changeType == "MODIFY" && !entry.ChangesSuppressed && len(entry.Changes) == 0 {
+				return
+			}
+			structured = entry
 		}
-		structured = entry
 	}
 
 	report.addEntry(key, options.SuppressedKinds, subjectKind, options.OutputContext, diffs, changeType, structured)

diff/diff_test.go

@@ -756,10 +756,14 @@ data:
 			key: makeMapping(":\n  not-valid: value"),
 		}
 
-		requireStructuredPanic(t, func() {
-			var buf bytes.Buffer
-			_ = Manifests(oldIndex, newIndex, opts, &buf)
-		}, "failed to build structured entry", "convert new manifest")
+		var buf bytes.Buffer
+		changed := Manifests(oldIndex, newIndex, opts, &buf)
+		require.True(t, changed, "Should report resource-level change even when YAML parsing fails")
+
+		var entries []StructuredEntry
+		require.NoError(t, json.Unmarshal(buf.Bytes(), &entries))
+		require.Len(t, entries, 1)
+		require.Equal(t, "MODIFY", entries[0].ChangeType)
 	})
 
 	t.Run("InvalidOldManifestYAML", func(t *testing.T) {
@@ -770,10 +774,14 @@ data:
 			key: makeMapping(validConfigMap),
 		}
 
-		requireStructuredPanic(t, func() {
-			var buf bytes.Buffer
-			_ = Manifests(oldIndex, newIndex, opts, &buf)
-		}, "failed to build structured entry", "convert old manifest")
+		var buf bytes.Buffer
+		changed := Manifests(oldIndex, newIndex, opts, &buf)
+		require.True(t, changed, "Should report resource-level change even when YAML parsing fails")
+
+		var entries []StructuredEntry
+		require.NoError(t, json.Unmarshal(buf.Bytes(), &entries))
+		require.Len(t, entries, 1)
+		require.Equal(t, "MODIFY", entries[0].ChangeType)
 	})
 
 	t.Run("ArrayDocumentProducesJSONUnmarshalError", func(t *testing.T) {
@@ -790,10 +798,14 @@ data:
 			key: makeMapping(listManifest),
 		}
 
-		requireStructuredPanic(t, func() {
-			var buf bytes.Buffer
-			_ = Manifests(map[string]*manifest.MappingResult{}, newIndex, opts, &buf)
-		}, "failed to build structured entry", "convert new manifest", "cannot unmarshal array")
+		var buf bytes.Buffer
+		changed := Manifests(map[string]*manifest.MappingResult{}, newIndex, opts, &buf)
+		require.True(t, changed, "Should report resource-level change even when JSON unmarshal fails")
+
+		var entries []StructuredEntry
+		require.NoError(t, json.Unmarshal(buf.Bytes(), &entries))
+		require.Len(t, entries, 1)
+		require.Equal(t, "ADD", entries[0].ChangeType)
 	})
 }
 
@@ -967,23 +979,6 @@ spec:
 		require.Empty(t, entries, "Should have no entries for empty manifests")
 	})
 }
-
-func requireStructuredPanic(t *testing.T, fn func(), substrings ...string) {
-	t.Helper()
-	defer func() {
-		if r := recover(); r != nil {
-			err, ok := r.(error)
-			require.True(t, ok, "panic should be an error, got %T", r)
-			for _, sub := range substrings {
-				require.Contains(t, err.Error(), sub)
-			}
-			return
-		}
-		t.Fatalf("expected panic but function completed successfully")
-	}()
-	fn()
-}
-
 func TestManifestsWithRedactedSecrets(t *testing.T) {
 	ansi.DisableColors(true)