CSS Grid algorithm 2/N: auto-placement (#57532)#57532
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Summary: Pull Request resolved: react#57532 Implements the CSS Grid auto placement algorithm ([§8.5](https://www.w3.org/TR/css-grid-1/#auto-placement-algo)). ## How? - **AutoPlacement** — the four-step placement algorithm. - **LinePlacement** — grid-line resolution ([§8.3](https://www.w3.org/TR/css-grid-1/#grid-placement-errors)), including invalid-input handling: `line 0` is treated as `auto`, and `span 0` / negative spans clamp to `1`. - **OccupancyGrid** — overlap tracking for placed items. - Unit tests (line resolution), algorithm tests, and regression tests for the invalid-input cases. ## Not yet implemented These will be introduced later. Default `grid-auto-flow` is `row` so it won't be an issue. - **Dense packing** (`grid-auto-flow: dense`) - **Column flow** (`grid-auto-flow: column`) ## Notes - Stacked on react/yoga#1923 (data structures); until that lands this diff also shows its `GridItem.h` / `GridTrack.h` — those belong to react/yoga#1923. cc - rozele This a small chunk from react/yoga#1894 PR. X-link: react/yoga#1994 Differential Revision: D111722622 Pulled By: rozele
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Summary: Pull Request resolved: react#57532 Implements the CSS Grid auto placement algorithm ([§8.5](https://www.w3.org/TR/css-grid-1/#auto-placement-algo)). ## How? - **AutoPlacement** — the four-step placement algorithm. - **LinePlacement** — grid-line resolution ([§8.3](https://www.w3.org/TR/css-grid-1/#grid-placement-errors)), including invalid-input handling: `line 0` is treated as `auto`, and `span 0` / negative spans clamp to `1`. - **OccupancyGrid** — overlap tracking for placed items. - Unit tests (line resolution), algorithm tests, and regression tests for the invalid-input cases. ## Not yet implemented These will be introduced later. Default `grid-auto-flow` is `row` so it won't be an issue. - **Dense packing** (`grid-auto-flow: dense`) - **Column flow** (`grid-auto-flow: column`) ## Notes - Stacked on react/yoga#1923 (data structures); until that lands this diff also shows its `GridItem.h` / `GridTrack.h` — those belong to react/yoga#1923. cc - rozele This a small chunk from react/yoga#1894 PR. X-link: react/yoga#1994 Differential Revision: D111722622 Pulled By: rozele
Summary: Pull Request resolved: react#57532 Implements the CSS Grid auto placement algorithm ([§8.5](https://www.w3.org/TR/css-grid-1/#auto-placement-algo)). ## How? - **AutoPlacement** — the four-step placement algorithm. - **LinePlacement** — grid-line resolution ([§8.3](https://www.w3.org/TR/css-grid-1/#grid-placement-errors)), including invalid-input handling: `line 0` is treated as `auto`, and `span 0` / negative spans clamp to `1`. - **OccupancyGrid** — overlap tracking for placed items. - Unit tests (line resolution), algorithm tests, and regression tests for the invalid-input cases. ## Not yet implemented These will be introduced later. Default `grid-auto-flow` is `row` so it won't be an issue. - **Dense packing** (`grid-auto-flow: dense`) - **Column flow** (`grid-auto-flow: column`) ## Notes - Stacked on react/yoga#1923 (data structures); until that lands this diff also shows its `GridItem.h` / `GridTrack.h` — those belong to react/yoga#1923. cc - rozele This a small chunk from react/yoga#1894 PR. X-link: react/yoga#1994 Differential Revision: D111722622 Pulled By: rozele
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Summary:
Implements the CSS Grid auto placement algorithm (§8.5).
How?
line 0is treated asauto, andspan 0/ negative spans clamp to1.Not yet implemented
These will be introduced later. Default
grid-auto-flowisrowso it won't be an issue.grid-auto-flow: dense)grid-auto-flow: column)Notes
GridItem.h/GridTrack.h— those belong to CSS Grid algorithm 1/N: data structures yoga#1923.cc - rozele This a small chunk from react/yoga#1894 PR.
X-link: react/yoga#1994
Differential Revision: D111722622
Pulled By: rozele