This project demonstrates a possible bug in the project gulp-typescript (https://github.com/ivogabe/gulp-typescript) when using both option options.declaration: true and options.allowJs: true together.

#Issue Whe options.allowJs: true is provided, both TS and JS files get transpiled. All is great.

When both options.allowJs: true and options.declaration: true are set, only the typescript files get transpiled and not the javascript files.

#Steps to reproduce

1. Pull this project with git clone
2. Pull dependencies with npm install
3. Start by building project with options.declaration: false by typing gulp without-declarations
4. Now verify that you have a directory named release/js which contains both testJS.js and testTS.js. This is as expected.
5. Now remove your release dir with rm -rf release
6. This time build project with options.declaration: true by typing gulp with-declarations
7. Look in releases/js and find that only testTS.js exists there and not the (originally) javascript file testJS.js.