cli/command/container: deprecate NewDiffFormat, DiffFormatWrite

cli/command/container/diff.go

@@ -33,7 +33,7 @@ func runDiff(ctx context.Context, dockerCLI command.Cli, containerID string) err
 	}
 	diffCtx := formatter.Context{
 		Output: dockerCLI.Out(),
-		Format: NewDiffFormat("{{.Type}} {{.Path}}"),
+		Format: newDiffFormat("{{.Type}} {{.Path}}"),
 	}
-	return DiffFormatWrite(diffCtx, changes)
+	return diffFormatWrite(diffCtx, changes)
 }

cli/command/container/formatter_diff.go

@@ -13,24 +13,37 @@ const (
 )
 
 // NewDiffFormat returns a format for use with a diff Context
+//
+// Deprecated: this function was only used internally and will be removed in the next release.
 func NewDiffFormat(source string) formatter.Format {
+	return newDiffFormat(source)
+}
+
+// newDiffFormat returns a format for use with a diff [formatter.Context].
+func newDiffFormat(source string) formatter.Format {
 	if source == formatter.TableFormatKey {
 		return defaultDiffTableFormat
 	}
 	return formatter.Format(source)
 }
 
 // DiffFormatWrite writes formatted diff using the Context
-func DiffFormatWrite(ctx formatter.Context, changes []container.FilesystemChange) error {
-	render := func(format func(subContext formatter.SubContext) error) error {
+//
+// Deprecated: this function was only used internally and will be removed in the next release.
+func DiffFormatWrite(fmtCtx formatter.Context, changes []container.FilesystemChange) error {
+	return diffFormatWrite(fmtCtx, changes)
+}
+
+// diffFormatWrite writes formatted diff using the [formatter.Context].
+func diffFormatWrite(fmtCtx formatter.Context, changes []container.FilesystemChange) error {
+	return fmtCtx.Write(newDiffContext(), func(format func(subContext formatter.SubContext) error) error {
 		for _, change := range changes {
 			if err := format(&diffContext{c: change}); err != nil {
 				return err
 			}
 		}
 		return nil
-	}
-	return ctx.Write(newDiffContext(), render)
+	})
 }
 
 type diffContext struct {
@@ -39,12 +52,14 @@ type diffContext struct {
 }
 
 func newDiffContext() *diffContext {
-	diffCtx := diffContext{}
-	diffCtx.Header = formatter.SubHeaderContext{
-		"Type": changeTypeHeader,
-		"Path": pathHeader,
+	return &diffContext{
+		HeaderContext: formatter.HeaderContext{
+			Header: formatter.SubHeaderContext{
+				"Type": changeTypeHeader,
+				"Path": pathHeader,
+			},
+		},
 	}
-	return &diffCtx
 }
 
 func (d *diffContext) MarshalJSON() ([]byte, error) {

cli/command/container/formatter_diff_test.go

@@ -16,23 +16,23 @@ func TestDiffContextFormatWrite(t *testing.T) {
 		expected string
 	}{
 		{
-			formatter.Context{Format: NewDiffFormat("table")},
+			formatter.Context{Format: newDiffFormat("table")},
 			`CHANGE TYPE   PATH
 C             /var/log/app.log
 A             /usr/app/app.js
 D             /usr/app/old_app.js
 `,
 		},
 		{
-			formatter.Context{Format: NewDiffFormat("table {{.Path}}")},
+			formatter.Context{Format: newDiffFormat("table {{.Path}}")},
 			`PATH
 /var/log/app.log
 /usr/app/app.js
 /usr/app/old_app.js
 `,
 		},
 		{
-			formatter.Context{Format: NewDiffFormat("{{.Type}}: {{.Path}}")},
+			formatter.Context{Format: newDiffFormat("{{.Type}}: {{.Path}}")},
 			`C: /var/log/app.log
 A: /usr/app/app.js
 D: /usr/app/old_app.js
@@ -50,7 +50,7 @@ D: /usr/app/old_app.js
 		t.Run(string(tc.context.Format), func(t *testing.T) {
 			out := bytes.NewBufferString("")
 			tc.context.Output = out
-			err := DiffFormatWrite(tc.context, diffs)
+			err := diffFormatWrite(tc.context, diffs)
 			if err != nil {
 				assert.Error(t, err, tc.expected)
 			} else {