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This method controls whether the builder needs to be called again again even if the layout constraints are the same.

By default, the builder will always be called when the widget is updated because the logic in the callback might have changed. However, there are cases where subclasses of ConstrainedLayoutBuilder know that certain property updates only affect paint and not build. In these cases, we lack a way of expressing that the builder callback is not needed -- and we end up doing superfluous work.

This PR gives subclasses the ability to know exactly when the callback needs to be called and when it can be skipped.

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@tvolkert tvolkert requested a review from goderbauer October 17, 2023 00:39
@github-actions github-actions bot added the framework flutter/packages/flutter repository. See also f: labels. label Oct 17, 2023
@tvolkert tvolkert force-pushed the updateShouldRebuild branch 4 times, most recently from a395c79 to be7a093 Compare October 21, 2023 16:52
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Done

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While this used to be the style, we now recommend against providing specialized getters for performance reasons because most callers don't care about the specific type (especially on the rebuild hot path) but still have to pay for the cast. Instead, just cast it at the two or three sides where you need the specific type. See also "Specializing the getters" in our docs: https://master-api.flutter.dev/flutter/widgets/RenderObjectElement-class.html.

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Done

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Maybe document explicitly that the new widget is asked if it requires a rebuild and it is given the old widget. Not the other way around.

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Done

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I find the wording "rebuilt" here a little confusing since this callback isn't on the Element.rebuild path. Maybe we can reword this to make it clear that this callback is consulted when the widget configuration is changed (i.e. the Element.update path)?

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Done

This method controls whether the builder needs to be called again
again even if the layout constraints are the same.

By default, the builder will always be called when the widget is
updated because the logic in the callback might have changed.
However, there are cases where subclasses of ConstrainedLayoutBuilder
know that certain property updates only affect paint and not build.
In these cases, we lack a way of expressing that the builder callback
is not needed -- and we end up doing superfluous work.

This PR gives subclasses the ability to know exactly when the
callback needs to be called and when it can be skipped.
@tvolkert tvolkert force-pushed the updateShouldRebuild branch from be7a093 to 08c562f Compare October 25, 2023 21:41
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Thanks! PTAL

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LGTM

@tvolkert tvolkert added the autosubmit Merge PR when tree becomes green via auto submit App label Oct 27, 2023
@auto-submit auto-submit bot merged commit 37da62a into flutter:master Oct 27, 2023
engine-flutter-autoroll added a commit to engine-flutter-autoroll/packages that referenced this pull request Oct 27, 2023
engine-flutter-autoroll added a commit to engine-flutter-autoroll/packages that referenced this pull request Oct 27, 2023
@tvolkert tvolkert deleted the updateShouldRebuild branch October 27, 2023 15:35
engine-flutter-autoroll added a commit to engine-flutter-autoroll/packages that referenced this pull request Oct 27, 2023
engine-flutter-autoroll added a commit to engine-flutter-autoroll/packages that referenced this pull request Oct 27, 2023
engine-flutter-autoroll added a commit to engine-flutter-autoroll/packages that referenced this pull request Oct 27, 2023
engine-flutter-autoroll added a commit to engine-flutter-autoroll/packages that referenced this pull request Oct 27, 2023
auto-submit bot pushed a commit to flutter/packages that referenced this pull request Oct 27, 2023
Roll Flutter from c555599 to 5907c97 (45 revisions)

flutter/flutter@c555599...5907c97

2023-10-27 [email protected] Add `isLogicalKeyPressed` to `KeyEvent` (flutter/flutter#136856)
2023-10-27 98614782+auto-submit[bot]@users.noreply.github.com Reverts "Ensure `flutter build apk --release` optimizes+shrinks platform code" (flutter/flutter#137433)
2023-10-27 [email protected] Roll Flutter Engine from bedc49efc85c to a198ad4e740d (20 revisions) (flutter/flutter#137429)
2023-10-27 [email protected] Make `SemanticsNode.isMergedIntoParent` Readonly (flutter/flutter#137304)
2023-10-27 [email protected] Manual roll Flutter Engine from bedc49efc85c to 71e1a0430232 (16 revisions) (flutter/flutter#137422)
2023-10-27 [email protected] Roll Packages from fea24c5 to 2af6954 (5 revisions) (flutter/flutter#137421)
2023-10-27 [email protected] Run tests on either macOS 12 or 13 (flutter/flutter#137365)
2023-10-27 [email protected] Revert "Update `DataTable` test when data row is pressed for Material 3 (#137230)" (flutter/flutter#137407)
2023-10-27 [email protected] Revert "Reland - Update `OutlinedButton` tests for Material 3 (#136809) (#137247)" (flutter/flutter#137406)
2023-10-27 [email protected] Ensure `flutter build apk --release` optimizes+shrinks platform code (flutter/flutter#136880)
2023-10-27 [email protected] Update `DataTable` test when data row is pressed for Material 3 (flutter/flutter#137230)
2023-10-27 [email protected] Reland - Update `OutlinedButton` tests for Material 3 (#136809) (flutter/flutter#137247)
2023-10-27 [email protected] update asset manifest file name referenced in `WebServiceWorker` (flutter/flutter#135954)
2023-10-27 [email protected] give `throwsToolExit` a more useful description (flutter/flutter#136694)
2023-10-27 [email protected] Add ConstrainedLayoutBuilder.updateShouldRebuild() (flutter/flutter#136691)
2023-10-27 [email protected] Fix. typos (flutter/flutter#137325)
2023-10-27 [email protected] Roll Flutter Engine from 87f384c2d70b to bedc49efc85c (1 revision) (flutter/flutter#137382)
2023-10-26 [email protected] Fix Typos (flutter/flutter#137292)
2023-10-26 [email protected] AnimationController should dispatch creation in constructor. (flutter/flutter#134839)
2023-10-26 [email protected] Roll Flutter Engine from 9788bb9ff83e to 87f384c2d70b (4 revisions) (flutter/flutter#137380)
2023-10-26 [email protected] Roll Flutter Engine from ce1c1ee54107 to 9788bb9ff83e (3 revisions) (flutter/flutter#137373)
2023-10-26 [email protected] Marks Windows_arm64 windows_startup_test to be unflaky (flutter/flutter#137228)
2023-10-26 [email protected] Marks Windows_arm64 flutter_tool_startup__windows to be unflaky (flutter/flutter#137229)
2023-10-26 [email protected] Marks Windows_arm64 windows_home_scroll_perf__timeline_summary to be unflaky (flutter/flutter#137221)
2023-10-26 [email protected] Declare dependency on copyFlutterAssetsTask in bundleAarTask (flutter/flutter#137370)
2023-10-26 [email protected] Marks Windows_arm64 complex_layout_win_desktop__start_up to be unflaky (flutter/flutter#137225)
2023-10-26 [email protected] Roll Flutter Engine from 394744d2c4d0 to ce1c1ee54107 (2 revisions) (flutter/flutter#137367)
2023-10-26 [email protected] Marks Windows_arm64 hot_mode_dev_cycle_win_target__benchmark to be unflaky (flutter/flutter#137217)
2023-10-26 [email protected] Marks Windows_arm64 flutter_view_win_desktop__start_up to be unflaky (flutter/flutter#137226)
2023-10-26 [email protected] Marks Windows_arm64 platform_view_win_desktop__start_up to be unflaky (flutter/flutter#137227)
2023-10-26 [email protected] Marks Windows_arm64 flutter_gallery_win_desktop__start_up to be unflaky (flutter/flutter#137224)
2023-10-26 [email protected] Marks Windows_arm64 hello_world_win_desktop__compile to be unflaky (flutter/flutter#137222)
2023-10-26 [email protected] Marks Windows_arm64 flutter_gallery_win_desktop__compile to be unflaky (flutter/flutter#137223)
2023-10-26 [email protected] Marks Windows_arm64 run_release_test_windows to be unflaky (flutter/flutter#137220)
2023-10-26 [email protected] Fix dislocated doc and comment on ThemeData localize cache (flutter/flutter#137315)
2023-10-26 [email protected] Marks Windows_arm64 platform_channel_sample_test_windows to be unflaky (flutter/flutter#137218)
2023-10-26 [email protected] Roll Flutter Engine from 7c5c8f587992 to 394744d2c4d0 (1 revision) (flutter/flutter#137364)
2023-10-26 [email protected] Roll Flutter Engine from 9363fe6ba503 to 7c5c8f587992 (3 revisions) (flutter/flutter#137363)
2023-10-26 [email protected] Roll Flutter Engine from 542f8bc4c019 to 9363fe6ba503 (2 revisions) (flutter/flutter#137354)
2023-10-26 [email protected] Unified analytics events for doctor validators (flutter/flutter#136647)
2023-10-26 [email protected] Roll Flutter Engine from d8132d5070bf to 542f8bc4c019 (2 revisions) (flutter/flutter#137349)
2023-10-26 [email protected] Marks Windows_arm64 run_debug_test_windows to be unflaky (flutter/flutter#137219)
2023-10-26 [email protected] Roll Flutter Engine from 0a6253dbfafd to d8132d5070bf (1 revision) (flutter/flutter#137347)
2023-10-26 [email protected] Roll Flutter Engine from 5da115661f01 to 0a6253dbfafd (1 revision) (flutter/flutter#137341)
2023-10-26 [email protected] Roll Flutter Engine from 61ae5ef94e9c to 5da115661f01 (1 revision) (flutter/flutter#137340)

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engine-flutter-autoroll added a commit to engine-flutter-autoroll/packages that referenced this pull request Feb 16, 2024
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