initial pass at deferred commands

Author: mccolljr

task.go

@@ -8,6 +8,7 @@ import (
 	"os"
 	"sync"
 	"sync/atomic"
+	"time"
 
 	"github.com/go-task/task/v3/internal/compiler"
 	compilerv2 "github.com/go-task/task/v3/internal/compiler/v2"
@@ -339,6 +340,11 @@ func (e *Executor) RunTask(ctx context.Context, call taskfile.Call) error {
 		}
 
 		for i := range t.Cmds {
+			if t.Cmds[i].Defer {
+				defer e.runDeferred(t, call, i)
+				continue
+			}
+
 			if err := e.runCommand(ctx, t, call, i); err != nil {
 				if err2 := e.statusOnError(t); err2 != nil {
 					e.Logger.VerboseErrf(logger.Yellow, "task: error cleaning status on error: %v", err2)
@@ -395,6 +401,14 @@ func (e *Executor) runDeps(ctx context.Context, t *taskfile.Task) error {
 	return g.Wait()
 }
 
+func (e *Executor) runDeferred(t *taskfile.Task, call taskfile.Call, i int) {
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second*10)
+	defer cancel()
+	if err := e.runCommand(ctx, t, call, i); err != nil {
+		e.Logger.VerboseErrf(logger.Yellow, `task: ignored error in deferred cmd: %s`, err.Error())
+	}
+}
+
 func (e *Executor) runCommand(ctx context.Context, t *taskfile.Task, call taskfile.Call, i int) error {
 	cmd := t.Cmds[i]
 

task_test.go

@@ -1044,6 +1044,32 @@ func TestRunOnlyRunsJobsHashOnce(t *testing.T) {
 	tt.Run(t)
 }
 
+func TestDeferredCmds(t *testing.T) {
+	const dir = "testdata/deferred"
+	var buff bytes.Buffer
+	e := task.Executor{
+		Dir:    dir,
+		Stdout: &buff,
+		Stderr: &buff,
+	}
+	assert.NoError(t, e.Setup())
+
+	expectedOutputOrder := strings.TrimSpace(`
+task: [task-2] echo 'cmd ran'
+cmd ran
+task: [task-2] exit 1
+task: [task-2] echo 'failing' && exit 2
+failing
+task: [task-2] echo 'echo ran'
+echo ran
+task: [task-1] echo 'task-1 ran'
+task-1 ran
+`)
+	assert.Error(t, e.Run(context.Background(), taskfile.Call{Task: "task-2"}))
+	fmt.Println(buff.String())
+	assert.Contains(t, buff.String(), expectedOutputOrder)
+}
+
 func TestIgnoreNilElements(t *testing.T) {
 	tests := []struct {
 		name string

taskfile/cmd.go

@@ -7,6 +7,7 @@ type Cmd struct {
 	Task        string
 	Vars        *Vars
 	IgnoreError bool
+	Defer       bool
 }
 
 // Dep is a task dependency
@@ -33,6 +34,18 @@ func (c *Cmd) UnmarshalYAML(unmarshal func(interface{}) error) error {
 		c.IgnoreError = cmdStruct.IgnoreError
 		return nil
 	}
+	var deferredCmd struct {
+		Defer string
+	}
+	if err := unmarshal(&deferredCmd); err == nil && deferredCmd.Defer != "" {
+		c.Defer = true
+		if strings.HasPrefix(deferredCmd.Defer, "^") {
+			c.Task = strings.TrimPrefix(deferredCmd.Defer, "^")
+		} else {
+			c.Cmd = deferredCmd.Defer
+		}
+		return nil
+	}
 	var taskCall struct {
 		Task string
 		Vars *Vars

taskfile/taskfile_test.go

@@ -19,6 +19,8 @@ vars:
   PARAM1: VALUE1
   PARAM2: VALUE2
 `
+		yamlDeferredTask = `defer: ^some_task`
+		yamlDeferredCmd  = `defer: echo 'test'`
 	)
 	tests := []struct {
 		content  string
@@ -41,6 +43,16 @@ vars:
 				},
 			}},
 		},
+		{
+			yamlDeferredCmd,
+			&taskfile.Cmd{},
+			&taskfile.Cmd{Cmd: "echo 'test'", Defer: true},
+		},
+		{
+			yamlDeferredTask,
+			&taskfile.Cmd{},
+			&taskfile.Cmd{Task: "some_task", Defer: true},
+		},
 		{
 			yamlDep,
 			&taskfile.Dep{},

testdata/deferred/Taskfile.yml

@@ -0,0 +1,12 @@
+version: "3"
+
+tasks:
+  task-1:
+    - echo 'task-1 ran'
+
+  task-2:
+    - defer: "^task-1"
+    - defer: echo 'echo ran'
+    - defer: echo 'failing' && exit 2
+    - echo 'cmd ran'
+    - exit 1

variables.go

@@ -102,6 +102,7 @@ func (e *Executor) compiledTask(call taskfile.Call, evaluateShVars bool) (*taskf
 				Cmd:         r.Replace(cmd.Cmd),
 				Vars:        r.ReplaceVars(cmd.Vars),
 				IgnoreError: cmd.IgnoreError,
+				Defer:       cmd.Defer,
 			})
 		}
 	}