Spec-correct CSS Flexbox §4.5 auto-min-size opt-in on YGConfig (re-land) (#1966)#1968
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Spec-correct CSS Flexbox §4.5 auto-min-size opt-in on YGConfig (re-land) (#1966)#1968adityasharat wants to merge 1 commit into
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…nd) (react#1966) Summary: Re-land of D105720159, originally reverted (revert: 0e642b96c7e2) due to a latent NPE in `ReactProgressBarViewManager.kt` and Instagram-internal `ReactSwitchManager.kt` — both fixed in the prior diffs in this stack. Crash and broken e2e tests reported in T273821098 / P2359486686. This re-land additionally fixes a correctness gap in the original D105720159 design: it claimed "Default configs carry the bit (preserves today's behaviour); existing trees see no change" — but `LayoutConformance::Strict` in `YogaLayoutableShadowNode::resolveErrata` returned `YGErrataNone`, which clears every errata bit *including* the new `MinSizeUndefinedInsteadOfAuto` (bit 8). Since `react-strict-dom` sets `experimental_layoutConformance="strict"` on every native View, this implicitly opts every RSD-using surface into the new auto-min probe. That's the exact path Airwave's tests took to hit the original NPE. Change: `LayoutConformance::Strict` now returns `YGErrataMinSizeUndefinedInsteadOfAuto` instead of `YGErrataNone`. Strict mode keeps every other CSS conformance behavior intact; only the new auto-min feature stays opt-in via explicit `YGConfig` setup. This matches the design pattern Litho uses in the child diff (`ComponentsConfiguration.useAutoMinSize` flag, gated independently of any strict-mode plumbing). Original summary follows: X-link: react/react-native#57015 Implements CSS Flexbox §4.5 automatic minimum sizing in Yoga. When opted in on a `YGConfig`, every flex item whose main-axis `min-{width,height}` is undefined receives a content-derived floor — `min(min-content, specified-size, max-size)` plus any aspect-ratio-transferred lower bound — so it cannot shrink below the size CSS browsers would honor. How to opt in: clear the new `YGErrataMinSizeUndefinedInsteadOfAuto` errata bit on the config. Default configs carry the bit (preserves today's behaviour); existing trees see no change. The bit is added to `YGErrataClassic` so consumers using that constant continue to get the same default. **`LayoutConformance::Strict` also keeps the bit set** — the new feature is strictly opt-in, not inferred from strict-mode CSS conformance. See D105720159 for full details on precedence rules, container recursion semantics, and per-item opt-outs. Changelog: [General][Added] - Add CSS Flexbox §4.5 automatic minimum sizing. Opt in by clearing the new `YGErrataMinSizeUndefinedInsteadOfAuto` errata bit on `YGConfig`. Differential Revision: D107183851
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…nd) (#57057) Summary: Pull Request resolved: #57057 X-link: react/yoga#1968 Re-land of D105720159, originally reverted (revert: 0e642b96c7e2) due to a latent NPE in `ReactProgressBarViewManager.kt` and Instagram-internal `ReactSwitchManager.kt` — both fixed in the prior diffs in this stack. Crash and broken e2e tests reported in T273821098 / P2359486686. This re-land additionally fixes a correctness gap in the original D105720159 design: it claimed "Default configs carry the bit (preserves today's behaviour); existing trees see no change" — but `LayoutConformance::Strict` in `YogaLayoutableShadowNode::resolveErrata` returned `YGErrataNone`, which clears every errata bit *including* the new `MinSizeUndefinedInsteadOfAuto` (bit 8). Since `react-strict-dom` sets `experimental_layoutConformance="strict"` on every native View, this implicitly opts every RSD-using surface into the new auto-min probe. That's the exact path Airwave's tests took to hit the original NPE. Change: `LayoutConformance::Strict` now returns `YGErrataMinSizeUndefinedInsteadOfAuto` instead of `YGErrataNone`. Strict mode keeps every other CSS conformance behavior intact; only the new auto-min feature stays opt-in via explicit `YGConfig` setup. This matches the design pattern Litho uses in the child diff (`ComponentsConfiguration.useAutoMinSize` flag, gated independently of any strict-mode plumbing). Original summary follows: X-link: react/yoga#1966 Pull Request resolved: #57015 Implements CSS Flexbox §4.5 automatic minimum sizing in Yoga. When opted in on a `YGConfig`, every flex item whose main-axis `min-{width,height}` is undefined receives a content-derived floor — `min(min-content, specified-size, max-size)` plus any aspect-ratio-transferred lower bound — so it cannot shrink below the size CSS browsers would honor. How to opt in: clear the new `YGErrataMinSizeUndefinedInsteadOfAuto` errata bit on the config. Default configs carry the bit (preserves today's behaviour); existing trees see no change. The bit is added to `YGErrataClassic` so consumers using that constant continue to get the same default. **`LayoutConformance::Strict` also keeps the bit set** — the new feature is strictly opt-in, not inferred from strict-mode CSS conformance. See D105720159 for full details on precedence rules, container recursion semantics, and per-item opt-outs. Changelog: [General][Added] - Add CSS Flexbox §4.5 automatic minimum sizing. Opt in by clearing the new `YGErrataMinSizeUndefinedInsteadOfAuto` errata bit on `YGConfig`. Reviewed By: javache, aashay-gaikwad Differential Revision: D107183851 fbshipit-source-id: 451b86347e24da5504649ba575fb27ae0d2f9853
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Summary:
Re-land of D105720159, originally reverted (revert: 0e642b96c7e2) due to a latent NPE in
ReactProgressBarViewManager.ktand Instagram-internalReactSwitchManager.kt— both fixed in the prior diffs in this stack. Crash and broken e2e tests reported in T273821098 / P2359486686.This re-land additionally fixes a correctness gap in the original D105720159 design: it claimed "Default configs carry the bit (preserves today's behaviour); existing trees see no change" — but
LayoutConformance::StrictinYogaLayoutableShadowNode::resolveErratareturnedYGErrataNone, which clears every errata bit including the newMinSizeUndefinedInsteadOfAuto(bit 8). Sincereact-strict-domsetsexperimental_layoutConformance="strict"on every native View, this implicitly opts every RSD-using surface into the new auto-min probe. That's the exact path Airwave's tests took to hit the original NPE.Change:
LayoutConformance::Strictnow returnsYGErrataMinSizeUndefinedInsteadOfAutoinstead ofYGErrataNone. Strict mode keeps every other CSS conformance behavior intact; only the new auto-min feature stays opt-in via explicitYGConfigsetup. This matches the design pattern Litho uses in the child diff (ComponentsConfiguration.useAutoMinSizeflag, gated independently of any strict-mode plumbing).Original summary follows:
X-link: facebook/react-native#57015
Implements CSS Flexbox §4.5 automatic minimum sizing in Yoga. When opted in on a
YGConfig, every flex item whose main-axismin-{width,height}is undefined receives a content-derived floor —min(min-content, specified-size, max-size)plus any aspect-ratio-transferred lower bound — so it cannot shrink below the size CSS browsers would honor.How to opt in: clear the new
YGErrataMinSizeUndefinedInsteadOfAutoerrata bit on the config. Default configs carry the bit (preserves today's behaviour); existing trees see no change. The bit is added toYGErrataClassicso consumers using that constant continue to get the same default.LayoutConformance::Strictalso keeps the bit set — the new feature is strictly opt-in, not inferred from strict-mode CSS conformance.See D105720159 for full details on precedence rules, container recursion semantics, and per-item opt-outs.
Changelog:
[General][Added] - Add CSS Flexbox §4.5 automatic minimum sizing. Opt in by clearing the new
YGErrataMinSizeUndefinedInsteadOfAutoerrata bit onYGConfig.Differential Revision: D107183851