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Nick Gerleman
1fe3ff86c3
Summary: Pull Request resolved: https://github.com/facebook/react-native/pull/51303 We do a lot of incorrect `cei()` in text measurement, compensated later by other incorrect bits. There are a couple of interesting bits here: A "desired width" is how large a hypothetical text layout would like to be. It is a floating point value, and to avoid truncation, a container must be larger than the desired width. So ceiling this is correct. We are also passed available width, which may be an exact specification, not at a subpixel boundary. Ceiling this is totally incorrect, since Yoga will disregard our ceiled version, and we just created a layout, larger than our actual measure will be. We must instead floor `availableWidth`, and we create our layout based off of that, to not give an extra physical pixel, that may not be given to us, if later layout rounding doesn't go our way. We then ceil `desiredWidth` earlier. Finally, when we have an exact measuremode, we create the layout so that it uses guaranteedWidth`, but act as if it takes the full available space, per-contract, which may be a subpixel size larger. This means we cannot create layouts which cause truncation. I used this change as an opportunity to clean up `createLayout()`, since we are gating anyways, to remove the duplicated paths, and to avoid the unnecessary `TextDirectionHeuristic` work for BoringLayout case, and since `StaticLayoutBuilder` already defaults to the heuristic we are manually setting. Changelog: [Android][Fixed] - Fix more text rounding bugs Reviewed By: joevilches Differential Revision: D74685353 fbshipit-source-id: 3700df657958c6efb46bfbbe674051d16a2b7c26