reinstate --select-1

buffer.go

@@ -115,23 +115,13 @@ func (mb *MemoryBuffer) LineAt(n int) (Line, error) {
 	return mb.lines[n], nil
 }
 
-// Source implements pipline.Source, and is the buffer for the input
-type Source struct {
-	pipeline.OutputChannel
-	MemoryBuffer
-
-	in        io.Reader
-	enableSep bool
-	ready     chan struct{}
-	setupOnce sync.Once
-}
-
 // Creates a new Source. Does not start processing the input until you
 // call Setup()
 func NewSource(in io.Reader, enableSep bool) *Source {
 	return &Source{
 		in:            in, // Note that this may be closed, so do not rely on it
 		enableSep:     enableSep,
+		done: make(chan struct{}),
 		ready:         make(chan struct{}),
 		setupOnce:     sync.Once{},
 		OutputChannel: pipeline.OutputChannel(make(chan interface{})),
@@ -212,6 +202,9 @@ func (s *Source) Setup(state *Peco) {
 		// XXX Just in case scanner.Scan() did not return a single line...
 		// Note: this will be a no-op if notify.Do has been called before
 		notify.Do(notifycb)
+		// And also, close the done channel so we can tell the consumers
+		// we have finished reading everything
+		close(s.done)
 
 		if pdebug.Enabled {
 			pdebug.Printf("Read all %d lines from source", readCount)
@@ -244,3 +237,9 @@ func (s *Source) Start(ctx context.Context) {
 func (s *Source) Ready() <-chan struct{} {
 	return s.ready
 }
+
+// Done returns the "read all lines" channel. It will be closed as soon as
+// the all input has been read
+func (s *Source) Done() <-chan struct{} {
+	return s.done
+}

interface.go

@@ -409,6 +409,18 @@ type FilterSet struct {
 	current int
 }
 
+// Source implements pipline.Source, and is the buffer for the input
+type Source struct {
+	pipeline.OutputChannel
+	MemoryBuffer
+
+	in        io.Reader
+	enableSep bool
+	done      chan struct{}
+	ready     chan struct{}
+	setupOnce sync.Once
+}
+
 type State interface {
 	Keymap() *Keymap
 	Query() Query

peco.go

@@ -232,6 +232,7 @@ func (p *Peco) Setup() (err error) {
 	}
 	p.source = src
 	p.ResetCurrentLineBuffer()
+
 	return nil
 }
 
@@ -286,6 +287,19 @@ func (p *Peco) Run(ctx context.Context) (err error) {
 	}
 
 	close(p.readyCh)
+	if p.Options.OptSelect1 {
+		go func() {
+			<-p.source.Done()
+			if b := p.CurrentLineBuffer(); b.Size() == 1 {
+				if l, err := b.LineAt(0); err == nil {
+					p.resultCh = make(chan Line)
+					p.Exit(nil)
+					p.resultCh <- l
+					close(p.resultCh)
+				}
+			}
+		}()
+	}
 	<-ctx.Done()
 
 	return p.Err()