Merge pull request #2335 from git-lfs/githistory-log-list-task

git/githistory/log: implement ListTask type

git/githistory/log/list_task.go

@@ -0,0 +1,41 @@
+package log
+
+import "fmt"
+
+// ListTask is a Task implementation that logs all updates in a list where each
+// entry is line-delimited.
+//
+// For example:
+//   entry #1
+//   entry #2
+//   msg: ..., done
+type ListTask struct {
+	msg string
+	ch  chan string
+}
+
+// NewListTask instantiates a new *ListTask instance with the given message.
+func NewListTask(msg string) *ListTask {
+	return &ListTask{
+		msg: msg,
+		ch:  make(chan string, 1),
+	}
+}
+
+// Entry logs a line-delimited task entry.
+func (l *ListTask) Entry(update string) {
+	l.ch <- fmt.Sprintf("%s\n", update)
+}
+
+func (l *ListTask) Complete() {
+	l.ch <- fmt.Sprintf("%s: ...", l.msg)
+	close(l.ch)
+}
+
+// Throttled implements the Task.Throttled function and ensures that all log
+// updates are printed to the sink.
+func (l *ListTask) Throttled() bool { return false }
+
+// Updates implements the Task.Updates function and returns a channel of updates
+// to log to the sink.
+func (l *ListTask) Updates() <-chan string { return l.ch }

git/githistory/log/list_task_test.go

@@ -0,0 +1,52 @@
+package log
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestListTaskCallsDoneWhenComplete(t *testing.T) {
+	task := NewListTask("example")
+	task.Complete()
+
+	select {
+	case update, ok := <-task.Updates():
+		assert.Equal(t, "example: ...", update)
+		assert.True(t, ok,
+			"git/githistory/log: expected Updates() to remain open")
+	default:
+		t.Fatal("git/githistory/log: expected update from *ListTask")
+	}
+
+	select {
+	case update, ok := <-task.Updates():
+		assert.False(t, ok,
+			"git/githistory.log: unexpected *ListTask.Update(): %s", update)
+	default:
+		t.Fatal("git/githistory/log: expected *ListTask.Updates() to be closed")
+	}
+}
+
+func TestListTaskWritesEntries(t *testing.T) {
+	task := NewListTask("example")
+	task.Entry("1")
+
+	select {
+	case update, ok := <-task.Updates():
+		assert.True(t, ok,
+			"git/githistory/log: expected ListTask.Updates() to remain open")
+		assert.Equal(t, "1\n", update)
+	default:
+		t.Fatal("git/githistory/log: expected task.Updates() to have an update")
+	}
+}
+
+func TestListTaskIsNotThrottled(t *testing.T) {
+	task := NewListTask("example")
+
+	throttled := task.Throttled()
+
+	assert.False(t, throttled,
+		"git/githistory/log: expected *ListTask to be Throttle()-d")
+}

git/githistory/log/log.go

@@ -94,6 +94,14 @@ func (l *Logger) Percentage(msg string, total uint64) *PercentageTask {
 	return t
 }
 
+// List creates and enqueues a new *ListTask.
+func (l *Logger) List(msg string) *ListTask {
+	t := NewListTask(msg)
+	l.enqueue(t)
+
+	return t
+}
+
 // enqueue enqueues the given Tasks "ts".
 func (l *Logger) enqueue(ts ...Task) {
 	if l == nil {