add support for print text during render progress bar

progressbar.go

@@ -1,6 +1,7 @@
 package progressbar
 
 import (
+	"bytes"
 	"errors"
 	"fmt"
 	"io"
@@ -121,6 +122,8 @@
 
 	// showDescriptionAtLineEnd specifies whether description should be written at line end instead of line start
 	showDescriptionAtLineEnd bool
+
+	stdBuffer bytes.Buffer
 }
 
 // Theme defines the elements of the bar
@@ -349,7 +352,7 @@
 		b.config.useIECUnits)
 
 	if b.config.renderWithBlankState {
 		b.RenderBlank()
 	}
 
 	return &b
@@ -607,7 +610,7 @@
 	if p.config.invisible {
 		return
 	}
 	p.render()
 }
 
 // New64 returns a new ProgressBar
@@ -655,7 +658,7 @@
 
 	p.lock.Unlock() // so p.Add can lock
 
 	p.Add(0) // re-render
 }
 
 // IsFinished returns true if progress bar is completed
@@ -689,7 +692,8 @@
 	if !p.state.finished && p.state.currentNum >= p.config.max {
 		p.state.finished = true
 		if !p.config.clearOnFinish {
+			io.Copy(p.config.writer, &p.config.stdBuffer)
 			renderProgressBar(p.config, &p.state)
 		}
 		if p.config.onCompletion != nil {
 			p.config.onCompletion()
@@ -707,6 +711,7 @@
 	}
 
 	// then, re-render the current progress bar
+	io.Copy(p.config.writer, &p.config.stdBuffer)
 	w, err := renderProgressBar(p.config, &p.state)
 	if err != nil {
 		return err
@@ -1042,7 +1047,7 @@
 		// ignore any errors in Sync(), as stdout
 		// can't be synced on some operating systems
 		// like Debian 9 (Stretch)
 		f.Sync()
 	}
 
 	return nil
@@ -1065,7 +1070,7 @@
 // Read will read the data and add the number of bytes to the progressbar
 func (r *Reader) Read(p []byte) (n int, err error) {
 	n, err = r.Reader.Read(p)
 	r.bar.Add(n)
 	return
 }
 
@@ -1074,7 +1079,7 @@
 	if closer, ok := r.Reader.(io.Closer); ok {
 		return closer.Close()
 	}
 	r.bar.Finish()
 	return
 }
 
@@ -1142,3 +1147,23 @@
 
 	return 0, err
 }
+
+func shouldCacheOutput(pb *ProgressBar) bool {
+	return !pb.state.finished && !pb.state.exit && !pb.config.invisible
+}
+
+func Bprintln(pb *ProgressBar, a ...interface{}) (int, error) {
+	if !shouldCacheOutput(pb) {
+		return fmt.Fprintln(pb.config.writer, a...)
+	} else {
+		return fmt.Fprintln(&pb.config.stdBuffer, a...)
+	}
+}
+
+func Bprintf(pb *ProgressBar, format string, a ...interface{}) (int, error) {
+	if !shouldCacheOutput(pb) {
+		return fmt.Fprintf(pb.config.writer, format, a...)
+	} else {
+		return fmt.Fprintf(&pb.config.stdBuffer, format, a...)
+	}
+}