Possibility to call another task

README.md

@@ -141,6 +141,28 @@ task2:
 
 Will stop at the moment the dependencies of `task2` are executed.
 
+### Calling a task from another task
+
+When a task has many dependencies, they are executed concurrently. This will
+often result in a faster build pipeline. But in some situations you may need
+to call other tasks serially. For this just prefix a command with `^`:
+
+```yml
+a-task:
+  cmds:
+    - ^another-task
+    - ^even-another-task
+    - echo "Both done"
+
+another-task:
+  cmds:
+    - ...
+
+even-another-task:
+  cmds:
+    - ...
+```
+
 ### Prevent task from running when not necessary
 
 If a task generates something, you can inform Task the source and generated

task.go

@@ -74,13 +74,17 @@ func Run() {
 
 // RunTask runs a task by its name
 func RunTask(name string) error {
-	mu.Lock()
-	if _, found := runnedTasks[name]; found {
+	if strings.HasPrefix(name, "^") {
+		name = strings.TrimPrefix(name, "^")
+	} else {
+		mu.Lock()
+		if _, found := runnedTasks[name]; found {
+			mu.Unlock()
+			return &cyclicDepError{name}
+		}
+		runnedTasks[name] = struct{}{}
 		mu.Unlock()
-		return &cyclicDepError{name}
 	}
-	runnedTasks[name] = struct{}{}
-	mu.Unlock()
 
 	t, ok := Tasks[name]
 	if !ok {
@@ -174,6 +178,14 @@ func (t *Task) runCommand(i int) error {
 	if err != nil {
 		return err
 	}
+
+	if strings.HasPrefix(c, "^") {
+		if err = RunTask(c); err != nil {
+			return err
+		}
+		return nil
+	}
+
 	dir, err := ReplaceVariables(t.Dir, vars)
 	if err != nil {
 		return err

task_test.go

@@ -85,3 +85,30 @@ func TestVars(t *testing.T) {
 		}
 	}
 }
+
+func TestTaskCall(t *testing.T) {
+	const dir = "testdata/task_call"
+
+	files := []string{
+		"foo.txt",
+		"bar.txt",
+	}
+
+	for _, f := range files {
+		_ = os.Remove(filepath.Join(dir, f))
+	}
+
+	c := exec.Command("task")
+	c.Dir = dir
+
+	if err := c.Run(); err != nil {
+		t.Error(err)
+		return
+	}
+
+	for _, f := range files {
+		if _, err := os.Stat(filepath.Join(dir, f)); err != nil {
+			t.Error(err)
+		}
+	}
+}

testdata/task_call/.gitignore

@@ -0,0 +1 @@
+*.txt

testdata/task_call/Taskfile.yml

@@ -0,0 +1,20 @@
+default:
+  cmds:
+    - ^set-foo
+    - ^print
+    - ^set-bar
+    - ^print
+
+print:
+  cmds:
+    - echo text > {{.FILE}}
+
+set-foo:
+  set: FILE
+  cmds:
+    - echo foo.txt
+
+set-bar:
+  set: FILE
+  cmds:
+    - echo bar.txt