refactor: Replace go-difflib with go-udiff and extract UnifiedDiff to pkg/udiff

cmd/protoc-gen-go-tableau-loader/embed/templates/hub.pc.go.tpl

@@ -5,6 +5,7 @@ import (
 	"sync/atomic"
 	"time"
 
+	"github.com/tableauio/loader/pkg/udiff"
 	"github.com/tableauio/tableau/format"
 	"github.com/tableauio/tableau/load"
 	"github.com/tableauio/tableau/store"
@@ -143,7 +144,7 @@ func (h *Hub) Store(dir string, format format.Format, options ...store.Option) e
 	return nil
 }
 
-// mutableCheck checks if the messagers are mutable or not.
+// mutableCheck checks if the messagers are mutated or not.
 func (h *Hub) mutableCheck() {
 	interval := h.opts.MutableCheck.Interval
 	if interval == 0 {
@@ -166,7 +167,7 @@ func (h *Hub) mutableCheck() {
 }
 
 func (h *Hub) onMutateDefault(name string, original, current proto.Message) {
-	text, _ := UnifiedDiff(original, current)
+	text, _ := udiff.UnifiedDiff(original, current)
 	fmt.Fprintf(os.Stderr,
 		"==== %s DIFF BEGIN ====\n%s==== %s DIFF END ====\n",
 		name, text, name)

cmd/protoc-gen-go-tableau-loader/embed/templates/util.pc.go.tpl

@@ -1,9 +1,5 @@
 import (
 	"errors"
-
-	"github.com/pmezard/go-difflib/difflib"
-	"github.com/tableauio/tableau/store"
-	"google.golang.org/protobuf/proto"
 )
 
 var ErrNotFound = errors.New("not found")
@@ -22,23 +18,3 @@ func GetMessager[T Messager](messagerMap MessagerMap) T {
 	messager, _ := messagerMap[t.Name()].(T)
 	return messager
 }
-
-// UnifiedDiff generates the proto message delta as a unified diff.
-func UnifiedDiff(original, current proto.Message) (string, error) {
-	originalText, err := store.MarshalToText(original, true)
-	if err != nil {
-		return "", err
-	}
-	currentText, err := store.MarshalToText(current, true)
-	if err != nil {
-		return "", err
-	}
-	diff := difflib.UnifiedDiff{
-		A:        difflib.SplitLines(string(originalText)),
-		B:        difflib.SplitLines(string(currentText)),
-		FromFile: "Original",
-		ToFile:   "Current",
-		Context:  3,
-	}
-	return difflib.GetUnifiedDiffString(diff)
-}

go.mod

@@ -3,11 +3,10 @@ module github.com/tableauio/loader
 go 1.21
 
 require (
+	github.com/aymanbagabas/go-udiff v0.2.0
 	github.com/iancoleman/strcase v0.3.0
-	github.com/pmezard/go-difflib v1.0.0
 	github.com/stretchr/testify v1.10.0
 	github.com/tableauio/tableau v0.15.1
-	golang.org/x/exp v0.0.0-20230418202329-0354be287a23
 	google.golang.org/protobuf v1.34.2
 )
 
@@ -18,6 +17,7 @@ require (
 	github.com/emirpasic/gods v1.18.1 // indirect
 	github.com/mitchellh/go-wordwrap v1.0.1 // indirect
 	github.com/mohae/deepcopy v0.0.0-20170929034955-c48cc78d4826 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/protocolbuffers/txtpbfmt v0.0.0-20240820135758-21b1d9897dc7 // indirect
 	github.com/richardlehane/mscfb v1.0.4 // indirect
 	github.com/richardlehane/msoleps v1.0.4 // indirect

go.sum

@@ -1,5 +1,7 @@
 github.com/antchfx/xpath v0.0.0-20170515025933-1f3266e77307 h1:C735MoY/X+UOx6SECmHk5pVOj51h839Ph13pEoY8UmU=
 github.com/antchfx/xpath v0.0.0-20170515025933-1f3266e77307/go.mod h1:Yee4kTMuNiPYJ7nSNorELQMr1J33uOpXDMByNYhvtNk=
+github.com/aymanbagabas/go-udiff v0.2.0 h1:TK0fH4MteXUDspT88n8CKzvK0X9O2xu9yQjWpi6yML8=
+github.com/aymanbagabas/go-udiff v0.2.0/go.mod h1:RE4Ex0qsGkTAJoQdQQCA0uG+nAzJO/pI/QwceO5fgrA=
 github.com/benbjohnson/clock v1.1.0 h1:Q92kusRqC1XV2MjkWETPvjJVqKetz1OzxZB7mHJLju8=
 github.com/benbjohnson/clock v1.1.0/go.mod h1:J11/hYXuz8f4ySSvYwY0FKfm+ezbsZBKZxNJlLklBHA=
 github.com/bufbuild/protocompile v0.10.0 h1:+jW/wnLMLxaCEG8AX9lD0bQ5v9h1RUiMKOBOT5ll9dM=
@@ -56,8 +58,6 @@ go.uber.org/zap v1.24.0 h1:FiJd5l1UOLj0wCgbSE0rwwXHzEdAZS6hiiSnxJN/D60=
 go.uber.org/zap v1.24.0/go.mod h1:2kMP+WWQ8aoFoedH3T2sq6iJ2yDWpHbP0f6MQbS9Gkg=
 golang.org/x/crypto v0.28.0 h1:GBDwsMXVQi34v5CCYUm2jkJvu4cbtru2U4TN2PSyQnw=
 golang.org/x/crypto v0.28.0/go.mod h1:rmgy+3RHxRZMyY0jjAJShp2zgEdOqj2AO7U0pYmeQ7U=
-golang.org/x/exp v0.0.0-20230418202329-0354be287a23 h1:4NKENAGIctmZYLK9W+X1kDK8ObBFqOSCJM6WE7CvkJY=
-golang.org/x/exp v0.0.0-20230418202329-0354be287a23/go.mod h1:CxIveKay+FTh1D0yPZemJVgC/95VzuuOLq5Qi4xnoYc=
 golang.org/x/image v0.18.0 h1:jGzIakQa/ZXI1I0Fxvaa9W7yP25TqT6cHIHn+6CqvSQ=
 golang.org/x/image v0.18.0/go.mod h1:4yyo5vMFQjVjUcVk4jEQcU9MGy/rulF5WvUILseCM2E=
 golang.org/x/net v0.30.0 h1:AcW1SDZMkb8IpzCdQUaIq2sP4sZ4zw+55h6ynffypl4=

internal/options/options.go

@@ -1,10 +1,10 @@
 package options
 
 import (
+	"slices"
 	"strings"
 
 	"github.com/tableauio/tableau/proto/tableaupb"
-	"golang.org/x/exp/slices"
 	"google.golang.org/protobuf/compiler/protogen"
 	"google.golang.org/protobuf/proto"
 	"google.golang.org/protobuf/reflect/protoreflect"

pkg/udiff/udiff.go

@@ -0,0 +1,20 @@
+package udiff
+
+import (
+	"github.com/aymanbagabas/go-udiff"
+	"github.com/tableauio/tableau/store"
+	"google.golang.org/protobuf/proto"
+)
+
+// UnifiedDiff generates the proto message delta as a unified diff.
+func UnifiedDiff(original, current proto.Message) (string, error) {
+	originalText, err := store.MarshalToText(original, true)
+	if err != nil {
+		return "", err
+	}
+	currentText, err := store.MarshalToText(current, true)
+	if err != nil {
+		return "", err
+	}
+	return udiff.Unified("Original", "Current", string(originalText), string(currentText)), nil
+}

pkg/udiff/udiff_test.go

@@ -0,0 +1,100 @@
+package udiff
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"google.golang.org/protobuf/types/known/structpb"
+	"google.golang.org/protobuf/types/known/wrapperspb"
+)
+
+func TestUnifiedDiff_NoDifference(t *testing.T) {
+	original := wrapperspb.String("hello")
+	current := wrapperspb.String("hello")
+
+	diff, err := UnifiedDiff(original, current)
+	require.NoError(t, err)
+	assert.Empty(t, diff)
+}
+
+func TestUnifiedDiff_WithDifference(t *testing.T) {
+	original := wrapperspb.String("hello")
+	current := wrapperspb.String("world")
+
+	diff, err := UnifiedDiff(original, current)
+	require.NoError(t, err)
+	assert.NotEmpty(t, diff)
+
+	// Assert full unified diff lines
+	assert.Contains(t, diff, "--- Original")
+	assert.Contains(t, diff, "+++ Current")
+	assert.Contains(t, diff, `-value: "hello"`)
+	assert.Contains(t, diff, `+value: "world"`)
+}
+
+func TestUnifiedDiff_NilMessages(t *testing.T) {
+	original := wrapperspb.String("")
+	current := wrapperspb.String("")
+
+	diff, err := UnifiedDiff(original, current)
+	require.NoError(t, err)
+	assert.Empty(t, diff)
+}
+
+func TestUnifiedDiff_ComplexMessage(t *testing.T) {
+	original, err := structpb.NewStruct(map[string]any{
+		"name":    "Alice",
+		"age":     30,
+		"active":  true,
+		"score":   99.5,
+		"address": map[string]any{"city": "Shanghai", "zip": "200000"},
+		"tags":    []any{"admin", "vip"},
+	})
+	require.NoError(t, err)
+
+	current, err := structpb.NewStruct(map[string]any{
+		"name":    "Bob",
+		"age":     25,
+		"active":  false,
+		"score":   88.0,
+		"address": map[string]any{"city": "Beijing", "zip": "100000"},
+		"tags":    []any{"user"},
+	})
+	require.NoError(t, err)
+
+	diff, err := UnifiedDiff(original, current)
+	require.NoError(t, err)
+	assert.NotEmpty(t, diff)
+
+	// Assert changed fields with full unified diff lines
+	assert.Contains(t, diff, "-    bool_value: true")
+	assert.Contains(t, diff, "+    bool_value: false")
+	assert.Contains(t, diff, `-          string_value: "Shanghai"`)
+	assert.Contains(t, diff, `+          string_value: "Beijing"`)
+	assert.Contains(t, diff, `-          string_value: "200000"`)
+	assert.Contains(t, diff, `+          string_value: "100000"`)
+	assert.Contains(t, diff, "-    number_value: 30")
+	assert.Contains(t, diff, "+    number_value: 25")
+	assert.Contains(t, diff, `-    string_value: "Alice"`)
+	assert.Contains(t, diff, `+    string_value: "Bob"`)
+	assert.Contains(t, diff, "-    number_value: 99.5")
+	assert.Contains(t, diff, "+    number_value: 88")
+	assert.Contains(t, diff, `-        string_value: "admin"`)
+	assert.Contains(t, diff, `-        string_value: "vip"`)
+	assert.Contains(t, diff, `+        string_value: "user"`)
+
+	// Assert unchanged fields (keys) are not in diff lines (no +/- prefix)
+	assert.NotContains(t, diff, `-  key: "active"`)
+	assert.NotContains(t, diff, `+  key: "active"`)
+	assert.NotContains(t, diff, `-  key: "address"`)
+	assert.NotContains(t, diff, `+  key: "address"`)
+	assert.NotContains(t, diff, `-  key: "age"`)
+	assert.NotContains(t, diff, `+  key: "age"`)
+	assert.NotContains(t, diff, `-  key: "name"`)
+	assert.NotContains(t, diff, `+  key: "name"`)
+	assert.NotContains(t, diff, `-  key: "score"`)
+	assert.NotContains(t, diff, `+  key: "score"`)
+	assert.NotContains(t, diff, `-  key: "tags"`)
+	assert.NotContains(t, diff, `+  key: "tags"`)
+}