pipe.MkDirAll runs instantly not sequentially in pipe.Script

[stephen-soltesz]

In a pipe.Script context, my expectation is that every step runs sequentially, where earlier steps complete before later steps start.

I discovered that a few functions like pipe.MkDirAll run instantly, irrespective of their position in the pipe.Script.

For example:

pipe.Script(
	pipe.System("sleep 2 && test ! -d newdir"),     // wait then fail.
	pipe.MkDirAll("newdir/subdir", 0755),           // runs before first step completes
),

If my understanding is correct, it looks like this behavior could be changed by using a TaskFunc in the implementation of MkDirAll.

For example:

func syncMkDirAll(dir string, perm os.FileMode) pipe.Pipe {
	return pipe.TaskFunc(func(s *pipe.State) error {
		return os.MkdirAll(s.Path(dir), perm)
	})
}

What do you think of making MkDir* a TaskFunc by default?

Thanks!