progress: support pinned messages with multiple lines (#233)

Author: jedib0t

cmd/demo-progress/demo.go

@@ -90,10 +90,8 @@ func trackSomething(pw progress.Writer, idx int64, updateMessage bool) {
 				tracker.MarkAsErrored()
 			}
 			pw.SetPinnedMessages(
-				fmt.Sprintf("Current Time: %s | Total Time: %s",
-					time.Now().Format(time.RFC3339),
-					time.Now().Sub(timeStart).Round(time.Second),
-				),
+				fmt.Sprintf(">> Current Time: %-32s", time.Now().Format(time.RFC3339)),
+				fmt.Sprintf(">>   Total Time: %-32s", time.Now().Sub(timeStart).Round(time.Millisecond)),
 			)
 		case <-updateTicker:
 			if updateMessage {

progress/progress.go

@@ -35,7 +35,8 @@ type Progress struct {
 	overallTracker        *Tracker
 	overallTrackerMutex   sync.RWMutex
 	pinnedMessages        []string
-	pinnedMessagesMutex   sync.RWMutex
+	pinnedMessageMutex    sync.RWMutex
+	pinnedMessageNumLines int
 	renderInProgress      bool
 	renderInProgressMutex sync.RWMutex
 	sortBy                SortBy
@@ -157,14 +158,6 @@ func (p *Progress) Log(msg string, a ...interface{}) {
 	p.logsToRenderMutex.Unlock()
 }
 
-// PinnedMessages returns the current pinned messages.
-func (p *Progress) PinnedMessages() []string {
-	p.pinnedMessagesMutex.RLock()
-	defer p.pinnedMessagesMutex.RUnlock()
-
-	return p.pinnedMessages
-}
-
 // SetAutoStop toggles the auto-stop functionality. Auto-stop set to true would
 // mean that the Render() function will automatically stop once all currently
 // active Trackers reach their final states. When set to false, the client code
@@ -197,8 +190,8 @@ func (p *Progress) SetOutputWriter(writer io.Writer) {
 // progress bar. This method can be used to overwrite all the pinned messages.
 // Call this function without arguments to "clear" the pinned messages.
 func (p *Progress) SetPinnedMessages(messages ...string) {
-	p.pinnedMessagesMutex.Lock()
-	defer p.pinnedMessagesMutex.Unlock()
+	p.pinnedMessageMutex.Lock()
+	defer p.pinnedMessageMutex.Unlock()
 
 	p.pinnedMessages = messages
 }

progress/progress_test.go

@@ -95,14 +95,6 @@ func TestProgress_Log(t *testing.T) {
 	assert.Len(t, p.logsToRender, 1)
 }
 
-func TestProgress_PinnedMessages(t *testing.T) {
-	p := Progress{}
-	assert.Nil(t, p.pinnedMessages)
-
-	p.pinnedMessages = []string{"pin1", "pin2"}
-	assert.Equal(t, []string{"pin1", "pin2"}, p.PinnedMessages())
-}
-
 func TestProgress_SetAutoStop(t *testing.T) {
 	p := Progress{}
 	assert.False(t, p.autoStop)

progress/render.go

@@ -159,22 +159,28 @@ func (p *Progress) moveCursorToTheTop(out *strings.Builder) {
 		numLinesToMoveUp++
 	}
 	if p.style.Visibility.Pinned {
-		numLinesToMoveUp += len(p.pinnedMessages)
+		numLinesToMoveUp += p.pinnedMessageNumLines
 	}
-	if numLinesToMoveUp > 0 {
-		out.WriteString(text.CursorUp.Sprintn(numLinesToMoveUp))
+	for numLinesToMoveUp > 0 {
+		out.WriteString(text.CursorUp.Sprint())
+		out.WriteString(text.EraseLine.Sprint())
+		numLinesToMoveUp--
 	}
 }
 
 func (p *Progress) renderPinnedMessages(out *strings.Builder) {
-	p.pinnedMessagesMutex.RLock()
-	defer p.pinnedMessagesMutex.RUnlock()
+	p.pinnedMessageMutex.RLock()
+	defer p.pinnedMessageMutex.RUnlock()
 
+	numLines := len(p.pinnedMessages)
 	for _, msg := range p.pinnedMessages {
-		out.WriteString(text.EraseLine.Sprint())
-		out.WriteString(p.Style().Colors.Pinned.Sprint(msg))
+		msg = strings.TrimSpace(msg)
+		out.WriteString(p.style.Colors.Pinned.Sprint(msg))
 		out.WriteRune('\n')
+
+		numLines += strings.Count(msg, "\n")
 	}
+	p.pinnedMessageNumLines = numLines
 }
 
 func (p *Progress) renderTracker(out *strings.Builder, t *Tracker, hint renderHint) {
@@ -194,7 +200,6 @@ func (p *Progress) renderTracker(out *strings.Builder, t *Tracker, hint renderHi
 		}
 	}
 
-	out.WriteString(text.EraseLine.Sprint())
 	if hint.isOverallTracker {
 		if !t.IsDone() {
 			hint := renderHint{hideValue: true, isOverallTracker: true}