progress: auto-trim output to fit terminal width

cmd/demo-progress/demo.go

@@ -118,11 +118,11 @@ func main() {
 	// instantiate a Progress Writer and set up the options
 	pw := progress.NewWriter()
 	pw.SetAutoStop(*flagAutoStop)
-	pw.SetTrackerLength(25)
-	pw.SetMessageWidth(24)
+	pw.SetMessageLength(24)
 	pw.SetNumTrackersExpected(*flagNumTrackers)
 	pw.SetSortBy(progress.SortByPercentDsc)
 	pw.SetStyle(progress.StyleDefault)
+	pw.SetTrackerLength(25)
 	pw.SetTrackerPosition(progress.PositionRight)
 	pw.SetUpdateFrequency(time.Millisecond * 100)
 	pw.Style().Colors = progress.StyleColorsExample

go.mod

@@ -6,5 +6,6 @@ require (
 	github.com/mattn/go-runewidth v0.0.13
 	github.com/pkg/profile v1.6.0
 	github.com/stretchr/testify v1.7.4
-	golang.org/x/sys v0.1.0
+	golang.org/x/sys v0.16.0
+	golang.org/x/term v0.16.0
 )

go.sum

@@ -14,8 +14,10 @@ github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSS
 github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.7.4 h1:wZRexSlwd7ZXfKINDLsO4r7WBt3gTKONc6K/VesHvHM=
 github.com/stretchr/testify v1.7.4/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
-golang.org/x/sys v0.1.0 h1:kunALQeHf1/185U1i0GOB/fy1IPRDDpuoOOqRReG57U=
-golang.org/x/sys v0.1.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.16.0 h1:xWw16ngr6ZMtmxDyKyIgsE93KNKz5HKmMa3b8ALHidU=
+golang.org/x/sys v0.16.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/term v0.16.0 h1:m+B6fahuftsE9qjo0VWp2FW0mB3MTJvR0BaMQrq0pmE=
+golang.org/x/term v0.16.0/go.mod h1:yn7UURbUtPyrVJPGPq404EukNFxcm/foM+bV/bfcDsY=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

progress/progress.go

@@ -1,14 +1,15 @@
 package progress
 
 import (
+	"context"
 	"fmt"
 	"io"
 	"os"
 	"sync"
 	"time"
-	"unicode/utf8"
 
 	"github.com/jedib0t/go-pretty/v6/text"
+	"golang.org/x/term"
 )
 
 var (
@@ -23,24 +24,27 @@ var (
 // Progress helps track progress for one or more tasks.
 type Progress struct {
 	autoStop              bool
-	done                  chan bool
+	lengthMessage         int
 	lengthProgress        int
 	lengthProgressOverall int
 	lengthTracker         int
 	logsToRender          []string
 	logsToRenderMutex     sync.RWMutex
-	messageWidth          int
 	numTrackersExpected   int64
 	outputWriter          io.Writer
 	overallTracker        *Tracker
 	overallTrackerMutex   sync.RWMutex
 	pinnedMessages        []string
 	pinnedMessageMutex    sync.RWMutex
 	pinnedMessageNumLines int
+	renderContext         context.Context
+	renderContextCancel   context.CancelFunc
 	renderInProgress      bool
 	renderInProgressMutex sync.RWMutex
 	sortBy                SortBy
 	style                 *Style
+	terminalWidth         int
+	terminalWidthOverride int
 	trackerPosition       Position
 	trackersActive        []*Tracker
 	trackersActiveMutex   sync.RWMutex
@@ -168,11 +172,19 @@ func (p *Progress) SetAutoStop(autoStop bool) {
 	p.autoStop = autoStop
 }
 
-// SetMessageWidth sets the (printed) length of the tracker message. Any message
-// longer the specified width will be snipped abruptly. Any message shorter than
+// SetMessageLength sets the (printed) length of the tracker message. Any
+// message longer the specified length will be snipped. Any message shorter than
 // the specified width will be padded with spaces.
+func (p *Progress) SetMessageLength(length int) {
+	p.lengthMessage = length
+}
+
+// SetMessageWidth sets the (printed) length of the tracker message. Any message
+// longer the specified width will be snipped. Any message shorter than the
+// specified width will be padded with spaces.
+// Deprecated: in favor of SetMessageLength(length)
 func (p *Progress) SetMessageWidth(width int) {
-	p.messageWidth = width
+	p.lengthMessage = width
 }
 
 // SetNumTrackersExpected sets the expected number of trackers to be tracked.
@@ -209,6 +221,12 @@ func (p *Progress) SetStyle(style Style) {
 	p.style = &style
 }
 
+// SetTerminalWidth sets up a sticky terminal width and prevents the Progress
+// Writer from polling for the real width during render.
+func (p *Progress) SetTerminalWidth(width int) {
+	p.terminalWidthOverride = width
+}
+
 // SetTrackerLength sets the text-length of all the Trackers.
 func (p *Progress) SetTrackerLength(length int) {
 	p.lengthTracker = length
@@ -266,7 +284,7 @@ func (p *Progress) ShowValue(show bool) {
 // Stop stops the Render() logic that is in progress.
 func (p *Progress) Stop() {
 	if p.IsRenderInProgress() {
-		p.done <- true
+		p.renderContextCancel()
 	}
 }
 
@@ -279,6 +297,13 @@ func (p *Progress) Style() *Style {
 	return p.style
 }
 
+func (p *Progress) getTerminalWidth() int {
+	if p.terminalWidthOverride > 0 {
+		return p.terminalWidthOverride
+	}
+	return p.terminalWidth
+}
+
 func (p *Progress) initForRender() {
 	// pick a default style
 	p.Style()
@@ -287,7 +312,7 @@ func (p *Progress) initForRender() {
 	}
 
 	// reset the signals
-	p.done = make(chan bool, 1)
+	p.renderContext, p.renderContextCancel = context.WithCancel(context.Background())
 
 	// pick default lengths if no valid ones set
 	if p.lengthTracker <= 0 {
@@ -297,13 +322,15 @@ func (p *Progress) initForRender() {
 	// calculate length of the actual progress bar by discounting the left/right
 	// border/box chars
 	p.lengthProgress = p.lengthTracker -
-		utf8.RuneCountInString(p.style.Chars.BoxLeft) -
-		utf8.RuneCountInString(p.style.Chars.BoxRight)
-	p.lengthProgressOverall = p.messageWidth +
+		text.RuneWidthWithoutEscSequences(p.style.Chars.BoxLeft) -
+		text.RuneWidthWithoutEscSequences(p.style.Chars.BoxRight)
+	p.lengthProgressOverall = p.lengthMessage +
 		text.RuneWidthWithoutEscSequences(p.style.Options.Separator) +
 		p.lengthProgress + 1
 	if p.style.Visibility.Percentage {
-		p.lengthProgressOverall += text.RuneWidthWithoutEscSequences(fmt.Sprintf(p.style.Options.PercentFormat, 0.0))
+		p.lengthProgressOverall += text.RuneWidthWithoutEscSequences(
+			fmt.Sprintf(p.style.Options.PercentFormat, 0.0),
+		)
 	}
 
 	// if not output write has been set, output to STDOUT
@@ -315,6 +342,29 @@ func (p *Progress) initForRender() {
 	if p.updateFrequency <= 0 {
 		p.updateFrequency = DefaultUpdateFrequency
 	}
+
+	// get the current terminal size for preventing roll-overs, and do this in a
+	// background loop until end of render
+	go p.watchTerminalSize() // needs p.updateFrequency
+}
+
+func (p *Progress) updateTerminalSize() {
+	p.terminalWidth, _, _ = term.GetSize(int(os.Stdout.Fd()))
+}
+
+func (p *Progress) watchTerminalSize() {
+	// once
+	p.updateTerminalSize()
+	// until end of time
+	ticker := time.NewTicker(time.Second / 10)
+	for {
+		select {
+		case <-ticker.C:
+			p.updateTerminalSize()
+		case <-p.renderContext.Done():
+			return
+		}
+	}
 }
 
 // renderHint has hints for the Render*() logic

progress/progress_test.go

@@ -1,6 +1,7 @@
 package progress
 
 import (
+	"context"
 	"math"
 	"os"
 	"testing"
@@ -143,6 +144,16 @@ func TestProgress_SetStyle(t *testing.T) {
 	assert.Equal(t, StyleCircle.Name, p.Style().Name)
 }
 
+func TestProgress_SetMessageLength(t *testing.T) {
+	p := Progress{}
+	assert.Equal(t, 0, p.lengthMessage)
+
+	p.SetMessageLength(80)
+	assert.Equal(t, 80, p.lengthMessage)
+	p.SetMessageWidth(81)
+	assert.Equal(t, 81, p.lengthMessage)
+}
+
 func TestProgress_SetTrackerLength(t *testing.T) {
 	p := Progress{}
 	assert.Equal(t, 0, p.lengthTracker)
@@ -222,13 +233,11 @@ func TestProgress_ShowValue(t *testing.T) {
 }
 
 func TestProgress_Stop(t *testing.T) {
-	doneChannel := make(chan bool, 1)
-
 	p := Progress{}
-	p.done = doneChannel
+	p.renderContext, p.renderContextCancel = context.WithCancel(context.Background())
 	p.renderInProgress = true
 	p.Stop()
-	assert.True(t, <-doneChannel)
+	assert.NotNil(t, <-p.renderContext.Done())
 }
 
 func TestProgress_Style(t *testing.T) {

progress/render.go

@@ -22,7 +22,7 @@ func (p *Progress) Render() {
 			select {
 			case <-ticker.C:
 				lastRenderLength = p.renderTrackers(lastRenderLength)
-			case <-p.done:
+			case <-p.renderContext.Done():
 				// always render the current state before finishing render in
 				// case it hasn't been shown yet
 				p.renderTrackers(lastRenderLength)
@@ -180,7 +180,11 @@ func (p *Progress) renderPinnedMessages(out *strings.Builder) {
 	numLines := len(p.pinnedMessages)
 	for _, msg := range p.pinnedMessages {
 		msg = strings.TrimSpace(msg)
-		out.WriteString(p.style.Colors.Pinned.Sprint(msg))
+		msg = p.style.Colors.Pinned.Sprint(msg)
+		if width := p.getTerminalWidth(); width > 0 {
+			msg = text.Trim(msg, width)
+		}
+		out.WriteString(msg)
 		out.WriteRune('\n')
 
 		numLines += strings.Count(msg, "\n")
@@ -192,28 +196,37 @@ func (p *Progress) renderTracker(out *strings.Builder, t *Tracker, hint renderHi
 	message := t.message()
 	message = strings.ReplaceAll(message, "\t", "    ")
 	message = strings.ReplaceAll(message, "\r", "")
-	if p.messageWidth > 0 {
+	if p.lengthMessage > 0 {
 		messageLen := text.RuneWidthWithoutEscSequences(message)
-		if messageLen < p.messageWidth {
-			message = text.Pad(message, p.messageWidth, ' ')
+		if messageLen < p.lengthMessage {
+			message = text.Pad(message, p.lengthMessage, ' ')
 		} else {
-			message = text.Snip(message, p.messageWidth, p.style.Options.SnipIndicator)
+			message = text.Snip(message, p.lengthMessage, p.style.Options.SnipIndicator)
 		}
 	}
 
+	tOut := &strings.Builder{}
+	tOut.Grow(p.lengthProgressOverall)
 	if hint.isOverallTracker {
 		if !t.IsDone() {
 			hint := renderHint{hideValue: true, isOverallTracker: true}
-			p.renderTrackerProgress(out, t, message, p.generateTrackerStr(t, p.lengthProgressOverall, hint), hint)
+			p.renderTrackerProgress(tOut, t, message, p.generateTrackerStr(t, p.lengthProgressOverall, hint), hint)
 		}
 	} else {
 		if t.IsDone() {
-			p.renderTrackerDone(out, t, message)
+			p.renderTrackerDone(tOut, t, message)
 		} else {
 			hint := renderHint{hideTime: !p.style.Visibility.Time, hideValue: !p.style.Visibility.Value}
-			p.renderTrackerProgress(out, t, message, p.generateTrackerStr(t, p.lengthProgress, hint), hint)
+			p.renderTrackerProgress(tOut, t, message, p.generateTrackerStr(t, p.lengthProgress, hint), hint)
 		}
 	}
+
+	outStr := tOut.String()
+	if width := p.getTerminalWidth(); width > 0 {
+		outStr = text.Trim(outStr, width)
+	}
+	out.WriteString(outStr)
+	out.WriteRune('\n')
 }
 
 func (p *Progress) renderTrackerDone(out *strings.Builder, t *Tracker, message string) {
@@ -225,7 +238,6 @@ func (p *Progress) renderTrackerDone(out *strings.Builder, t *Tracker, message s
 		out.WriteString(p.style.Colors.Error.Sprint(p.style.Options.ErrorString))
 	}
 	p.renderTrackerStats(out, t, renderHint{hideTime: !p.style.Visibility.Time, hideValue: !p.style.Visibility.Value})
-	out.WriteRune('\n')
 }
 
 func (p *Progress) renderTrackerMessage(out *strings.Builder, t *Tracker, message string) {
@@ -252,7 +264,6 @@ func (p *Progress) renderTrackerProgress(out *strings.Builder, t *Tracker, messa
 	if hint.isOverallTracker {
 		out.WriteString(p.style.Colors.Tracker.Sprint(trackerStr))
 		p.renderTrackerStats(out, t, hint)
-		out.WriteRune('\n')
 	} else if p.trackerPosition == PositionRight {
 		p.renderTrackerMessage(out, t, message)
 		out.WriteString(p.style.Colors.Message.Sprint(p.style.Options.Separator))
@@ -261,7 +272,6 @@ func (p *Progress) renderTrackerProgress(out *strings.Builder, t *Tracker, messa
 			out.WriteString(p.style.Colors.Tracker.Sprint(" " + trackerStr))
 		}
 		p.renderTrackerStats(out, t, hint)
-		out.WriteRune('\n')
 	} else {
 		p.renderTrackerPercentage(out, t)
 		if p.style.Visibility.Tracker {
@@ -270,7 +280,6 @@ func (p *Progress) renderTrackerProgress(out *strings.Builder, t *Tracker, messa
 		p.renderTrackerStats(out, t, hint)
 		out.WriteString(p.style.Colors.Message.Sprint(p.style.Options.Separator))
 		p.renderTrackerMessage(out, t, message)
-		out.WriteRune('\n')
 	}
 }
 
@@ -301,7 +310,7 @@ func (p *Progress) renderTrackers(lastRenderLength int) int {
 
 	// stop if auto stop is enabled and there are no more active trackers
 	if p.autoStop && p.LengthActive() == 0 {
-		p.done <- true
+		p.renderContextCancel()
 	}
 
 	return out.Len()