mock tty using interfaces to test more easily

packer/tty.go

@@ -0,0 +1,5 @@
+package packer
+
+type TTY interface {
+	ReadString() (string, error)
+}

packer/ui.go

@@ -82,7 +82,7 @@ type BasicUi struct {
 	ErrorWriter io.Writer
 	l           sync.Mutex
 	interrupted bool
-	tty         *tty.TTY
+	tty         TTY
 	StackableProgressBar
 }
 
@@ -235,7 +235,7 @@ func (rw *BasicUi) Ask(query string) (string, error) {
 			log.Printf("ui: scan err: %s", err)
 			return
 		}
-		result <- line
+		result <- strings.TrimSpace(line)
 	}()
 
 	select {

packer/ui_test.go

@@ -34,9 +34,18 @@ func testUi() *BasicUi {
 		Reader:      new(bytes.Buffer),
 		Writer:      new(bytes.Buffer),
 		ErrorWriter: new(bytes.Buffer),
+		tty:         new(testTTY),
 	}
 }
 
+type testTTY struct {
+	say string
+}
+
+func (tttyy *testTTY) ReadString() (string, error) {
+	return tttyy.say, nil
+}
+
 func TestColoredUi(t *testing.T) {
 	bufferUi := testUi()
 	ui := &ColoredUi{UiColorYellow, UiColorRed, bufferUi}
@@ -217,7 +226,7 @@ func TestBasicUi_Ask(t *testing.T) {
 	for _, testCase := range testCases {
 		// Because of the internal bufio we can't easily reset the input, so create a new one each time
 		bufferUi := testUi()
-		writeReader(bufferUi, testCase.Input)
+		bufferUi.tty = &testTTY{testCase.Input}
 
 		actual, err = bufferUi.Ask(testCase.Prompt)
 		if err != nil {