Add new flag 'shell' which outputs shell commands from a task

cmd/task/task.go

@@ -3,6 +3,7 @@ package main
 import (
  "context"
  "fmt"
+ "io"
  "log"
  "os"
  "path/filepath"
@@ -87,6 +88,7 @@ func run() error {
  color bool
  interval time.Duration
  global bool
+ shell bool
  )
 
  pflag.BoolVar(&versionFlag, "version", false, "Show Task version.")
@@ -115,6 +117,7 @@ func run() error {
  pflag.IntVarP(&concurrency, "concurrency", "C", 0, "Limit number tasks to run concurrently.")
  pflag.DurationVarP(&interval, "interval", "I", 0, "Interval to watch for changes.")
  pflag.BoolVarP(&global, "global", "g", false, "Runs global Taskfile, from $HOME/Taskfile.{yml,yaml}.")
+ pflag.BoolVarP(&shell, "shell", "", false, "Dump raw shell script")
  pflag.Parse()
 
  if versionFlag {
@@ -235,6 +238,12 @@ func run() error {
  return err
  }
 
+ if shell {
+ e.Shell = true
+ // disable all other logs except purely shell output
+ e.Logger.Stdout = io.Discard
+ }
+
  if e.Taskfile.Version.Compare(taskfile.V3) >= 0 {
  calls, globals = args.ParseV3(tasksAndVars...)
  } else {

precondition.go

@@ -15,6 +15,11 @@ var ErrPreconditionFailed = errors.New("task: precondition not met")
 
 func (e *Executor) areTaskPreconditionsMet(ctx context.Context, t *taskfile.Task) (bool, error) {
  for _, p := range t.Preconditions {
+ // log precondition command if shell flag is passed
+ if e.Shell {
+ e.Logger.FOutf(e.Stdout, logger.Default, "%s\n", p.Sh)
+ return true, nil
+ }
  err := execext.RunCommand(ctx, &execext.RunCommandOptions{
  Command: p.Sh,
  Dir: t.Dir,

task.go

@@ -46,6 +46,7 @@ type Executor struct {
  Verbose bool
  Silent bool
  Dry bool
+ Shell bool
  Summary bool
  Parallel bool
  Color bool
@@ -278,6 +279,11 @@ func (e *Executor) runCommand(ctx context.Context, t *taskfile.Task, call taskfi
  return nil
  }
 
+ if e.Shell {
+ e.Logger.FOutf(e.Stdout, logger.Default, "%s\n", cmd.Cmd)
+ return nil
+ }
+
  if e.Verbose || (!cmd.Silent && !t.Silent && !e.Taskfile.Silent && !e.Silent) {
  e.Logger.Errf(logger.Green, "task: [%s] %s", t.Name(), cmd.Cmd)
  }

task_test.go

@@ -1892,3 +1892,27 @@ func TestSplitArgs(t *testing.T) {
  require.NoError(t, err)
  assert.Equal(t, "3\n", buff.String())
 }
+
+func TestShell(t *testing.T) {
+ // reuse testdata/dry since 'shell' flag has similar behavior
+ const dir = "testdata/dry"
+
+ file := filepathext.SmartJoin(dir, "file.txt")
+ _ = os.Remove(file)
+
+ var buff bytes.Buffer
+
+ e := task.Executor{
+ Dir: dir,
+ Stdout: &buff,
+ Stderr: io.Discard,
+ Shell: true,
+ }
+ require.NoError(t, e.Setup())
+ require.NoError(t, e.Run(context.Background(), taskfile.Call{Task: "build"}))
+
+ assert.Equal(t, "touch file.txt", strings.TrimSpace(buff.String()))
+ if _, err := os.Stat(file); err == nil {
+ t.Errorf("File should not exist %s", file)
+ }
+}