fix: linear gradient color stop fix up spec

[intergalacticspacehighway]

Summary:

• Color stops needs to follow fix up spec
• Adds multiple stops syntax support. e.g. linear-gradient(red 30% 50%, green).
• Rename position to positions in object style API. Optional string array here makes more sense. We'll add number array support once px support is added. Will do it as a follow up to this PR.

TODOs: transition hint syntax support linear-gradient(red, 50%, green) (Done locally, dependent on this PR). px support.

Changelog:

[GENERAL] [FIXED] - Linear gradient color stop spec.

Test Plan:

• Added testcases in processBackgroundImage-test.js

[NickGerleman]

Going to mostly trust this based off of the unit tests. Function notation parsing is one of the first things on my list, once I get started back on that again.

I suspect when I turned on “ReactNativeFeatureFlags.enableBackgroundStyleApplicator, I broke gradients on Android, since the new path is on the composite drawbable. I haven’t looked around at fixing that up yet. I think it might look like “BackgroundStyleApplicator.setBackgroundImage()”.

[intergalacticspacehighway]

Function notation parsing

yeah i agree to move everything to cpp parser eventually. I built a tiny parser in JS for this syntax instead of using regex. But this is working fine for now.

ReactNativeFeatureFlags.enableBackgroundStyleApplicator. haven’t looked around at fixing that up yet

yes, it has affected the borders. Will take a look and do a PR by this weekend

[facebook-github-bot]

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[facebook-github-bot]

@NickGerleman merged this pull request in 1a49892.

[react-native-bot]

This pull request was successfully merged by @intergalacticspacehighway in 1a49892

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