AssertionError: Task function must be specified – Code Example

There is a significant change in gulp 4.0 which leads to assertionerror when using syntax of gulp 3. one such change is the way tasks are defined. Instead of list parameters, gulp 4.0+ uses gulp.series() and gulp.parallel(). Using otherwise can lead to AssertionError: Task function must be specified.

Code Example

The below code will create assertionerror –

gulp.task('default', ['task1', 'task2','task3']);

Replace it with this –

gulp.task('default', gulp.series('task1', 'task2','task3'));