pkg: Move edit.capturePort to eval.CaptureStringPort.

pkg/edit/instant.go

@@ -1,17 +1,10 @@
 package edit
 
 import (
-	"bufio"
-	"io"
-	"os"
-	"sync"
-
 	"github.com/elves/elvish/pkg/cli"
 	"github.com/elves/elvish/pkg/cli/addons/instant"
 	"github.com/elves/elvish/pkg/eval"
-	"github.com/elves/elvish/pkg/eval/vals"
 	"github.com/elves/elvish/pkg/parse"
-	"github.com/elves/elvish/pkg/strutil"
 )
 
 //elvdoc:var -instant:binding
@@ -40,7 +33,7 @@ func initInstant(ed *Editor, ev *eval.Evaler, nb eval.NsBuilder) {
 
 func instantStart(app cli.App, ev *eval.Evaler, binding cli.Handler) {
 	execute := func(code string) ([]string, error) {
-		outPort, collect, err := capturePort()
+		outPort, collect, err := eval.CaptureStringPort()
 		if err != nil {
 			return nil, err
 		}
@@ -53,41 +46,3 @@ func instantStart(app cli.App, ev *eval.Evaler, binding cli.Handler) {
 	}
 	instant.Start(app, instant.Config{Binding: binding, Execute: execute})
 }
-
-// Like eval.CapturePort, but collects output into strings, with value outputs
-// stringified and prepended a marker.
-func capturePort() (*eval.Port, func() []string, error) {
-	var lines []string
-	var mu sync.Mutex
-	addLine := func(line string) {
-		mu.Lock()
-		defer mu.Unlock()
-		lines = append(lines, line)
-	}
-	port, done, err := eval.PipePort(
-		func(ch <-chan interface{}) {
-			for v := range ch {
-				addLine("▶ " + vals.ToString(v))
-			}
-		},
-		func(r *os.File) {
-			bufr := bufio.NewReader(r)
-			for {
-				line, err := bufr.ReadString('\n')
-				if err != nil {
-					if err != io.EOF {
-						addLine("i/o error: " + err.Error())
-					}
-					break
-				}
-				addLine(strutil.ChopLineEnding(line))
-			}
-		})
-	if err != nil {
-		return nil, nil, err
-	}
-	return port, func() []string {
-		done()
-		return lines
-	}, nil
-}

pkg/eval/port.go

@@ -7,6 +7,7 @@ import (
 	"os"
 	"sync"
 
+	"github.com/elves/elvish/pkg/eval/vals"
 	"github.com/elves/elvish/pkg/strutil"
 )
 
@@ -149,3 +150,41 @@ func CapturePort() (*Port, func() []interface{}, error) {
 		return vs
 	}, nil
 }
+
+// CaptureStringPort is like CapturePort, but processes value outputs by
+// stringifying them and prepending an output marker.
+func CaptureStringPort() (*Port, func() []string, error) {
+	var lines []string
+	var mu sync.Mutex
+	addLine := func(line string) {
+		mu.Lock()
+		defer mu.Unlock()
+		lines = append(lines, line)
+	}
+	port, done, err := PipePort(
+		func(ch <-chan interface{}) {
+			for v := range ch {
+				addLine("▶ " + vals.ToString(v))
+			}
+		},
+		func(r *os.File) {
+			bufr := bufio.NewReader(r)
+			for {
+				line, err := bufr.ReadString('\n')
+				if err != nil {
+					if err != io.EOF {
+						addLine("i/o error: " + err.Error())
+					}
+					break
+				}
+				addLine(strutil.ChopLineEnding(line))
+			}
+		})
+	if err != nil {
+		return nil, nil, err
+	}
+	return port, func() []string {
+		done()
+		return lines
+	}, nil
+}