Cancel other executing targets when one fails.

plan.go

@@ -157,10 +157,18 @@ func (p *Plan) newTarget(ctx context.Context, target string) (Target, error) {
 // Rule. Targets Exec functions are gauranteed to be called when all of the
 // Targets dependencies have been fulfilled.
 func (p *Plan) Exec(ctx context.Context, semaphore Semaphore) error {
+	ctx, cancel := context.WithCancel(ctx)
+	defer cancel()
+
 	return p.graph.Walk(func(t Target) error {
 		semaphore.P()
 		defer semaphore.V()
-		return t.Exec(ctx)
+		err := t.Exec(ctx)
+		if err != nil {
+			// Cancel all other currently executing targets.
+			cancel()
+		}
+		return err
 	})
 }
 

plan_test.go

@@ -45,10 +45,20 @@ func TestPlan_Cancel(t *testing.T) {
 	ctx, cancel := context.WithTimeout(ctx, 1*time.Second)
 	defer cancel()
 	err := Exec(ctx, NewSemaphore(0), "test/000-cancel/all").(*dag.MultiError)
-	assert.Equal(t, 1, len(err.Errors))
+	assert.Equal(t, 2, len(err.Errors))
 	assert.True(t, strings.Contains(err.Errors[0].Error(), "signal: killed"))
 }
 
+func TestPlan_Cancel_Fail(t *testing.T) {
+	clean(t)
+
+	err := Exec(ctx, NewSemaphore(0), "test/000-cancel/all", "test/000-cancel/fail").(*dag.MultiError)
+	assert.Equal(t, 3, len(err.Errors))
+	assert.True(t, strings.Contains(err.Errors[0].Error(), "exit status 1"))
+	assert.True(t, strings.Contains(err.Errors[1].Error(), "signal: killed"))
+	assert.True(t, strings.Contains(err.Errors[2].Error(), "signal: killed"))
+}
+
 func TestTarget_Dependencies(t *testing.T) {
 	wd, err := os.Getwd()
 	assert.NoError(t, err)

test/000-cancel/all.walk

@@ -1,5 +1,10 @@
 #!/bin/bash
 
+deps() {
+  echo a.sleep
+  echo b.sleep
+}
+
 case $1 in
-  exec) exec sleep 60 ;;
+  deps) deps ;;
 esac

test/000-cancel/default.sleep.walk

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+case $1 in
+  exec) echo "Sleeping..." && exec sleep 60 ;;
+esac

test/000-cancel/fail.walk

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+case $1 in
+  exec) exit 1 ;;
+esac