Running gulp tasks in sequence throws `Unhandled stream error in pipe`

[aimad-majdou]

What were you expecting to happen?

To run 3 tasks in sequence, the first one is just to run a build command, the second one will delete a folder and it's content, the third one will copy files from a source into a destination (which was the deleted folder).

So basically the tasks definition is as following :

gulp.task('build-files, function(cb) {
    runSequence('run-build-cmd',
        'delete-dest', 'copy-files',
        cb);
});
gulp.task('delete-dest', (cb) => {
    del([pathToDestFolder], {force: true});
    cb();
});
gulp.task('copy-files', () => {
    return gulp.src(pathToSrcFolder)
        .pipe(gulp.dest(pathToDestFolder))
        .pipe(gulp.dest(anotherPath));
});

This task will run whenever changes happened in the source folder as following :

gulp.watch(pathToSrcFolder, ['build-files']);

When I run the gulp delete-dest in cmd prompt (which will clear the pathToDestFolder) and then gulp copy-files (which will copy the source folder into two folders pathToDestFolder and anotherPath) it works as expected .

So I guess runSequence didn't work as expected ?

I tried to use rimraf instead of del, and all seems to work just fine, I know that rimraf is depricated, and it's better to use del instead, but why del in this case results in an exception ?

What actually happened?

Error was thrown:

internal/streams/legacy.js:59
      throw er; // Unhandled stream error in pipe.
      ^

Error: ENOENT: no such file or directory, chmod 'pathToDestFolder\path\to\some\file\file.ext'

What version of gulp are you using?

3.9.1

What versions of npm and node are you using?

npm -v & node -v
5.6.0
v8.9.4

[stephenlacy]

This is a support issue, not an error with gulp.

Your issue is that del is returning before the file is actually deleted, and it gets deleted when your subsequent tasks are running. Use del.sync

[support]

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