Annotating taggedTemplateLiteral calls as #__PURE__

[Andarist]

Q	A
Fixed Issues	Fixes #6324, fixes #5900
Patch: Bug Fix?	no
Major: Breaking Change?	no
Minor: New Feature?	yes
Tests Added/Pass?	yes
Spec Compliancy?	n/a
License	MIT
Doc PR	no
Any Dependency Changes?	no

[babel-bot]

Build successful! You can test your changes in the REPL here: https://babeljs.io/repl/build/5072/

[brikou]

Great!

[Andarist]

@brikou keep in mind that this will make only taggedTemplateLiteral calls tree-shakeable, but you also need to mark as pure your css calls. You can do that with pure_funcs option of UglifyJS.

[brikou]

thank you very much for your insights 👍

[Andarist]

@brikou You might be interested in the plugin I'm creating.

When I add this feature it might help consumers of your component library (assuming you distribute one - if not its still advised to just use pure_funcs of the UglifyJS).

[jridgewell]

Feel free to merge, this is a simple enough change.