packer: Ui error output is red

command/build/command.go

@@ -101,8 +101,8 @@ func (c Command) Run(env packer.Environment, args []string) int {
 		var ui packer.Ui
 
 		ui = &packer.ColoredUi{
-			colors[i%len(colors)],
-			env.Ui(),
+			Color: colors[i%len(colors)],
+			Ui: env.Ui(),
 		}
 
 		ui = &packer.PrefixedUi{

packer/ui.go

@@ -29,6 +29,7 @@ type Ui interface {
 // ColoredUi is a UI that is colored using terminal colors.
 type ColoredUi struct {
 	Color      UiColor
+	ErrorColor UiColor
 	Ui         Ui
 }
 
@@ -48,24 +49,29 @@ type ReaderWriterUi struct {
 }
 
 func (u *ColoredUi) Say(message string) {
-	u.Ui.Say(u.colorize(message, true))
+	u.Ui.Say(u.colorize(message, u.Color, true))
 }
 
 func (u *ColoredUi) Message(message string) {
-	u.Ui.Message(u.colorize(message, false))
+	u.Ui.Message(u.colorize(message, u.Color, false))
 }
 
 func (u *ColoredUi) Error(message string) {
-	u.Ui.Error(u.colorize(message, false))
+	color := u.ErrorColor
+	if color == 0 {
+		color = UiColorRed
+	}
+
+	u.Ui.Error(u.colorize(message, color, true))
 }
 
-func (u *ColoredUi) colorize(message string, bold bool) string {
+func (u *ColoredUi) colorize(message string, color UiColor, bold bool) string {
 	attr := 0
 	if bold {
 		attr = 1
 	}
 
-	return fmt.Sprintf("\033[%d;%d;40m%s\033[0m", attr, u.Color, message)
+	return fmt.Sprintf("\033[%d;%d;40m%s\033[0m", attr, color, message)
 }
 
 func (u *PrefixedUi) Say(message string) {

packer/ui_test.go

@@ -14,13 +14,26 @@ func testUi() *ReaderWriterUi {
 }
 
 func TestColoredUi(t *testing.T) {
-	assert := asserts.NewTestingAsserts(t, true)
-
 	bufferUi := testUi()
-	ui := &ColoredUi{UiColorRed, bufferUi}
+	ui := &ColoredUi{UiColorYellow, UiColorRed, bufferUi}
 
 	ui.Say("foo")
-	assert.Equal(readWriter(bufferUi), "\033[1;31;40mfoo\033[0m\n", "should have color")
+	result := readWriter(bufferUi)
+	if result != "\033[1;33;40mfoo\033[0m\n" {
+		t.Fatalf("invalid output: %s", result)
+	}
+
+	ui.Message("foo")
+	result = readWriter(bufferUi)
+	if result != "\033[0;33;40mfoo\033[0m\n" {
+		t.Fatalf("invalid output: %s", result)
+	}
+
+	ui.Error("foo")
+	result = readWriter(bufferUi)
+	if result != "\033[1;31;40mfoo\033[0m\n" {
+		t.Fatalf("invalid output: %s", result)
+	}
 }
 
 func TestPrefixedUi(t *testing.T) {