Allow merge commands to specify overwrite and append simultaneously

commands_test.go

@@ -1091,6 +1091,25 @@ c:
 `
 	test.AssertResult(t, expectedOutput, result.Output)
 }
+
+func TestMergeOverwriteAndAppendCmd(t *testing.T) {
+	cmd := getRootCommand()
+	result := test.RunCmd(cmd, "merge --append --overwrite examples/data1.yaml examples/data2.yaml")
+	if result.Error != nil {
+		t.Error(result.Error)
+	}
+	expectedOutput := `a: other
+b:
+- 1
+- 2
+- 3
+- 4
+c:
+  test: 1
+`
+	test.AssertResult(t, expectedOutput, result.Output)
+}
+
 func TestMergeArraysCmd(t *testing.T) {
 	cmd := getRootCommand()
 	result := test.RunCmd(cmd, "merge --append examples/sample_array.yaml examples/sample_array_2.yaml")

pkg/yqlib/lib.go

@@ -58,11 +58,13 @@ func (l *lib) DeletePath(dataBucket interface{}, path string) (interface{}, erro
 	return l.navigator.DeleteChildValue(dataBucket, paths)
 }
 
-func (l *lib) Merge(dst interface{}, src interface{}, overwrite bool, append bool) error {
-	if overwrite {
-		return mergo.Merge(dst, src, mergo.WithOverride)
-	} else if append {
-		return mergo.Merge(dst, src, mergo.WithAppendSlice)
+func (l *lib) Merge(dst interface{}, src interface{}, overwriteFlag bool, appendFlag bool) error {
+	opts := []func(*mergo.Config){}
+	if overwriteFlag {
+		opts = append(opts, mergo.WithOverride)
 	}
-	return mergo.Merge(dst, src)
+	if appendFlag {
+		opts = append(opts, mergo.WithAppendSlice)
+	}
+	return mergo.Merge(dst, src, opts...)
 }

pkg/yqlib/lib_test.go

@@ -156,6 +156,23 @@ b: 2
 		test.AssertResult(t, `[{a b} {c d} {a 1} {b 2}]`, fmt.Sprintf("%v", mergedData["root"]))
 	})
 
+	t.Run("TestMerge_WithAppendAndOverwrite", func(t *testing.T) {
+		var dst = map[interface{}]interface{}{
+			"a": "initial",
+			"b": []string{"old"},
+		}
+		var src = map[interface{}]interface{}{
+			"a": "replaced",
+			"b": []string{"new"},
+		}
+
+		err := subject.Merge(&dst, src, true, true)
+		if err != nil {
+			t.Fatal("Unexpected error")
+		}
+		test.AssertResult(t, `map[a:replaced b:[old new]]`, fmt.Sprintf("%v", dst))
+	})
+
 	t.Run("TestMerge_WithError", func(t *testing.T) {
 		err := subject.Merge(nil, nil, false, false)
 		if err == nil {