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[web] Support local screenshot and golden testing in felt test - #191318
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Enables local screenshot testing in felt test by downloading baselines from Skia Gold, performing local pixel diffing (both precise and fuzzy), and caching baselines on disk. Fixes flutter#191314 Part of flutter#191313
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This pull request introduces local caching and offline capabilities for Flutter Web Engine golden screenshot tests, allowing baseline images to be fetched from Skia Gold, cached locally, and compared offline. Key feedback includes optimizing comparePixels by reusing Pixel instances to reduce garbage collection pressure, draining the HTTP response stream on 404 in SkiaGoldClient to prevent socket leaks, using asynchronous file I/O in _getGolden, and wrapping file rename operations in a try-catch block to handle concurrent file access robustly on Windows.
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This pull request implements offline support and local caching for Flutter Web Engine golden screenshot tests. It introduces local pixel-by-pixel comparison (supporting fuzzy and precise algorithms), baseline caching under .dart_tool/web_goldens_cache, and offline execution flags. Review feedback suggests optimizing the fuzzy 3x3 neighborhood matching by checking the exact center pixel first to short-circuit the search, and draining the HTTP response streams in SkiaGoldClient before throwing exceptions to prevent potential socket leaks.
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autosubmit label was removed for flutter/flutter/191318, because - The status or check suite Dashboard Checks has failed. Please fix the issues identified (or deflake) before re-applying this label. |
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autosubmit label was removed for flutter/flutter/191318, because - The status or check suite Dashboard Checks has failed. Please fix the issues identified (or deflake) before re-applying this label. |
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flutter/flutter@b444e78...63b9518 2026-09-09 [email protected] Roll Packages from 9af9c60 to 36e088a (24 revisions) (flutter/flutter#192485) 2026-09-09 [email protected] Re-add Xcode and OpenJDK dependencies to macOS wasm local_engine builders (flutter/flutter#192238) 2026-09-09 [email protected] Roll Dart SDK from 77094991d1c1 to 4be1b711b4ba (5 revisions) (flutter/flutter#192453) 2026-09-09 [email protected] [material] Use super parameters in more places (flutter/flutter#192149) 2026-09-09 [email protected] [cupertino] Use super parameters in more places (flutter/flutter#192148) 2026-09-09 [email protected] [flutter_tools] Gracefully handle EROFS and write-protected file system errors (flutter/flutter#192431) 2026-09-09 [email protected] [tool] Migrate BuildIOSCommand and BuildIOSArchiveCommand to modular dependency injection (flutter/flutter#192250) 2026-09-09 [email protected] Replace more enum instances comparison to use `equality ==` instead of `identical` and update related tests (flutter/flutter#192229) 2026-09-09 [email protected] [web] Support local screenshot and golden testing in felt test (flutter/flutter#191318) 2026-09-09 [email protected] [tool] Migrate DaemonCommand and DebugAdapterCommand to modular dependency injection (flutter/flutter#190793) 2026-09-09 [email protected] [web] Support local golden testing in flutter test (flutter/flutter#191386) 2026-09-09 [email protected] [flutter_tools] Ignore widget previews outside lib/ during LSP code generation (flutter/flutter#192326) 2026-09-09 [email protected] [flutter_tools] Read package_config.json asynchronously in loadPackageConfigWithLogging (flutter/flutter#192443) 2026-09-08 [email protected] Add precacheTestImage to flutter_test and unskip web image tests (flutter/flutter#191435) 2026-09-08 [email protected] et: Fix compile_commands.json post-processing (flutter/flutter#192395) 2026-09-08 [email protected] Refactor createDebuggingOptions and option registrations to OptionDescriptor (flutter/flutter#192307) 2026-09-08 [email protected] [flutter_tools] Fix test separation between `VersionFreshnessValidator` and `FlutterVersion.checkFlutterVersionFreshness` (flutter/flutter#191593) 2026-09-08 [email protected] [tool] Migrate EmulatorsCommand to modular dependency injection (flutter/flutter#190769) 2026-09-08 [email protected] [tool] Migrate Desktop build subcommands and toolchain to modular dependency injection (flutter/flutter#190781) 2026-09-08 [email protected] [tool] Migrate Tooling and Analysis commands to modular dependency injection (flutter/flutter#190788) 2026-09-08 [email protected] Skip KGP version validation for AGP built-in Kotlin (flutter/flutter#192206) If this roll has caused a breakage, revert this CL and set the roller to dry run mode using the controls here: https://autoroll.skia.org/r/flutter-packages Please CC [email protected],[email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Packages: https://github.com/flutter/flutter/issues/new/choose To report a problem with the AutoRoller itself, please file a bug: https://issues.skia.org/issues/new?component=1389291&template=1850622 Documentation for the AutoRoller is here: https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md
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…r#12814) flutter/flutter@b444e78...63b9518 2026-09-09 [email protected] Roll Packages from 9af9c60 to 36e088a (24 revisions) (flutter/flutter#192485) 2026-09-09 [email protected] Re-add Xcode and OpenJDK dependencies to macOS wasm local_engine builders (flutter/flutter#192238) 2026-09-09 [email protected] Roll Dart SDK from 77094991d1c1 to 4be1b711b4ba (5 revisions) (flutter/flutter#192453) 2026-09-09 [email protected] [material] Use super parameters in more places (flutter/flutter#192149) 2026-09-09 [email protected] [cupertino] Use super parameters in more places (flutter/flutter#192148) 2026-09-09 [email protected] [flutter_tools] Gracefully handle EROFS and write-protected file system errors (flutter/flutter#192431) 2026-09-09 [email protected] [tool] Migrate BuildIOSCommand and BuildIOSArchiveCommand to modular dependency injection (flutter/flutter#192250) 2026-09-09 [email protected] Replace more enum instances comparison to use `equality ==` instead of `identical` and update related tests (flutter/flutter#192229) 2026-09-09 [email protected] [web] Support local screenshot and golden testing in felt test (flutter/flutter#191318) 2026-09-09 [email protected] [tool] Migrate DaemonCommand and DebugAdapterCommand to modular dependency injection (flutter/flutter#190793) 2026-09-09 [email protected] [web] Support local golden testing in flutter test (flutter/flutter#191386) 2026-09-09 [email protected] [flutter_tools] Ignore widget previews outside lib/ during LSP code generation (flutter/flutter#192326) 2026-09-09 [email protected] [flutter_tools] Read package_config.json asynchronously in loadPackageConfigWithLogging (flutter/flutter#192443) 2026-09-08 [email protected] Add precacheTestImage to flutter_test and unskip web image tests (flutter/flutter#191435) 2026-09-08 [email protected] et: Fix compile_commands.json post-processing (flutter/flutter#192395) 2026-09-08 [email protected] Refactor createDebuggingOptions and option registrations to OptionDescriptor (flutter/flutter#192307) 2026-09-08 [email protected] [flutter_tools] Fix test separation between `VersionFreshnessValidator` and `FlutterVersion.checkFlutterVersionFreshness` (flutter/flutter#191593) 2026-09-08 [email protected] [tool] Migrate EmulatorsCommand to modular dependency injection (flutter/flutter#190769) 2026-09-08 [email protected] [tool] Migrate Desktop build subcommands and toolchain to modular dependency injection (flutter/flutter#190781) 2026-09-08 [email protected] [tool] Migrate Tooling and Analysis commands to modular dependency injection (flutter/flutter#190788) 2026-09-08 [email protected] Skip KGP version validation for AGP built-in Kotlin (flutter/flutter#192206) If this roll has caused a breakage, revert this CL and set the roller to dry run mode using the controls here: https://autoroll.skia.org/r/flutter-packages Please CC [email protected],[email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Packages: https://github.com/flutter/flutter/issues/new/choose To report a problem with the AutoRoller itself, please file a bug: https://issues.skia.org/issues/new?component=1389291&template=1850622 Documentation for the AutoRoller is here: https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md
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…r#12814) flutter/flutter@b444e78...63b9518 2026-09-09 [email protected] Roll Packages from 9af9c60 to 36e088a (24 revisions) (flutter/flutter#192485) 2026-09-09 [email protected] Re-add Xcode and OpenJDK dependencies to macOS wasm local_engine builders (flutter/flutter#192238) 2026-09-09 [email protected] Roll Dart SDK from 77094991d1c1 to 4be1b711b4ba (5 revisions) (flutter/flutter#192453) 2026-09-09 [email protected] [material] Use super parameters in more places (flutter/flutter#192149) 2026-09-09 [email protected] [cupertino] Use super parameters in more places (flutter/flutter#192148) 2026-09-09 [email protected] [flutter_tools] Gracefully handle EROFS and write-protected file system errors (flutter/flutter#192431) 2026-09-09 [email protected] [tool] Migrate BuildIOSCommand and BuildIOSArchiveCommand to modular dependency injection (flutter/flutter#192250) 2026-09-09 [email protected] Replace more enum instances comparison to use `equality ==` instead of `identical` and update related tests (flutter/flutter#192229) 2026-09-09 [email protected] [web] Support local screenshot and golden testing in felt test (flutter/flutter#191318) 2026-09-09 [email protected] [tool] Migrate DaemonCommand and DebugAdapterCommand to modular dependency injection (flutter/flutter#190793) 2026-09-09 [email protected] [web] Support local golden testing in flutter test (flutter/flutter#191386) 2026-09-09 [email protected] [flutter_tools] Ignore widget previews outside lib/ during LSP code generation (flutter/flutter#192326) 2026-09-09 [email protected] [flutter_tools] Read package_config.json asynchronously in loadPackageConfigWithLogging (flutter/flutter#192443) 2026-09-08 [email protected] Add precacheTestImage to flutter_test and unskip web image tests (flutter/flutter#191435) 2026-09-08 [email protected] et: Fix compile_commands.json post-processing (flutter/flutter#192395) 2026-09-08 [email protected] Refactor createDebuggingOptions and option registrations to OptionDescriptor (flutter/flutter#192307) 2026-09-08 [email protected] [flutter_tools] Fix test separation between `VersionFreshnessValidator` and `FlutterVersion.checkFlutterVersionFreshness` (flutter/flutter#191593) 2026-09-08 [email protected] [tool] Migrate EmulatorsCommand to modular dependency injection (flutter/flutter#190769) 2026-09-08 [email protected] [tool] Migrate Desktop build subcommands and toolchain to modular dependency injection (flutter/flutter#190781) 2026-09-08 [email protected] [tool] Migrate Tooling and Analysis commands to modular dependency injection (flutter/flutter#190788) 2026-09-08 [email protected] Skip KGP version validation for AGP built-in Kotlin (flutter/flutter#192206) If this roll has caused a breakage, revert this CL and set the roller to dry run mode using the controls here: https://autoroll.skia.org/r/flutter-packages Please CC [email protected],[email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Packages: https://github.com/flutter/flutter/issues/new/choose To report a problem with the AutoRoller itself, please file a bug: https://issues.skia.org/issues/new?component=1389291&template=1850622 Documentation for the AutoRoller is here: https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md
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Enables local screenshot testing in felt test by downloading baselines from Skia Gold, performing local pixel diffing (both precise and fuzzy), and caching baselines on disk.
Fixes #191314
Fixes #63710
Part of #191313
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