Grunt clean:dynamic task does not delete file/s from /build during grunt watch task

[netweb]

When running the Grunt task grunt watch a file that is modified and saved should be cleaned from the /build folder and the modified file copied from the /src folder to the /build folder as part of the watch:all task:

tasks: [ 'clean:dynamic', 'copy:dynamic' ],

Currently the clean:dynamic task does not actually 'clean' (delete) the file from the /build folder, the copy:dynamic task overwrites the existing file.

Workaround: Do nothing and continue to have the file overwritten without cleaning first.

Options:

1. Fix the clean:dynamic task to actually 'clean' (delete) the file from /build

2. Remove the clean:dynamic task from the clean and watch:all tasks list

To reproduce:

• Temporarilly remove copy:dynamic from the watch:all task tasks list
• Run grunt watch
• Edit a file from /src and save

Expected Results:

• Edited file should be 'cleaned' (deleted) in /build folder

Actual results:

• File remains in /build folder

See also replicated upstream ticket for WordPress Core: ​#WP29066