Add macOS support

[amgleitman]

Summary

This adds macOS support to react-native-svg.

A good amount of code for react-native-svg iOS, such as constructing paths, is already platform-agnostic, but there were a few big things that needed to be resolved, mostly related to type differences between macOS and iOS (for example, importing <UIKIt/UIKit.h> and differences between NSView/UIView, NSColor/UIColor, etc.), as well as a couple of iOS concepts that don't appear to have direct macOS equivalent (like -[UIView tintColor], which we use to determine what "currentColor" is).

Most of the heavy lifting in resolving platform differences lies in RNSVGUIKit.h, which is a similar strategy to what react-native-macos does with RCTUIKit.h (found here).

Test Plan

To verify that nothing broke, I created a test app and confirmed that the example SVGs shown in this repo's README render exactly the same.

Screenshot Comparison

macOS	iOS

Compatibility

OS	Implemented
iOS	N/A
Android	N/A
macOS	✅

Checklist

• I have tested this on a device and a simulator
• I added documentation in README.md
• I updated the typed files (typescript)
• I added a test for the API in the __tests__ folder

[jacobp100]

@amgleitman Thank you so much for working on this! Looks like a huge undertaking. It's been one of the things holding me back from using rn-macos and this will help a lot

[amgleitman]

@msand, can you take a look at this?

[jacobp100]

@amgleitman Do you have a published version of https://github.com/microsoft/react-native-svg-macos?

[amgleitman]

@amgleitman Do you have a published version of https://github.com/microsoft/react-native-svg-macos?

@jacobp100 Not yet, but we're working on it.

[jacobp100]

Ok. Thanks for your work on this! It'll be really helpful

[msand]

This is really impressive work! I hope to have some time and energy to dedicate to open source soon, becoming a father this spring, and our startup is growing quickly atm...

[HeyImChris]

This is really impressive work! I hope to have some time and energy to dedicate to open source soon, becoming a father this spring, and our startup is growing quickly atm...

To give us some flexibility with contributing to this repo, do you think it'd be possible to give @amgleitman write permissions so he can merge in the Mac support change? Either way, congrats on the startup and soon-to-be fathering!

[vincentjames501]

This is awesome! @msand do you have any thoughts to @HeyImChris 's question?

[msand]

I just added @amgleitman to the repository with write rights. Think I'll announce in a separate issue that this repo is looking for more maintainers and add a link to the readme. Thanks for any help in this!

[amgleitman]

Thanks @msand! Can I assume that I have your blessing to merge this PR and help maintain this repo in the future?

[vomchik]

@amgleitman do you have the source code of the SVG content(all you show on screenshots)? I want to try to write tests for this library.

[amgleitman]

@amgleitman do you have the source code of the SVG content(all you show on screenshots)? I want to try to write tests for this library.

I took the examples from the README file.

[vomchik]

@amgleitman do you have the source code of the SVG content(all you show on screenshots)? I want to try to write tests for this library.

I took the examples from the README file.

i see :) thanks