[Tool Robustness] Gracefully handle asynchronous subprocess crashes and connection timeouts#186964
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This pull request enhances error handling for the analysis server and web debug service connections by introducing a custom exception for server exits and specific timeout handling for web runners. Feedback indicates that the TimeoutException handler in resident_web_runner.dart is unreachable due to its placement after a generic Exception block. Furthermore, a .catchError block in the same file is noted as redundant, potentially causing duplicate error logging and state errors.
| .catchError((Object error, StackTrace stackTrace) { | ||
| _logger.printError( | ||
| 'Failed to establish connection with the web debug service: $error', | ||
| ); | ||
| appFailedToStart(); | ||
| throwToolExit('Failed to connect to the web debug service.'); | ||
| }), |
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This .catchError block introduces redundant error handling and a potential bug. Since connectDebug is already awaited and handled in the run() method (lines 390-400), both blocks will execute upon a connection failure. This leads to duplicate error logging and multiple ToolExit calls.
Furthermore, calling appFailedToStart() twice may not be idempotent; if it completes a Completer without an isCompleted check, the second call will throw a StateError, causing the tool to crash with an unhandled exception—the exact scenario this PR aims to prevent. Additionally, the stackTrace is currently ignored in the _logger.printError call here.
Consider simplifying this block to only ensure the future chain is handled, or log to trace for debugging purposes.
.catchError((Object error, StackTrace stackTrace) {
// This error is handled in ResidentWebRunner.run.
_logger.printTrace('Error in web debug connection: $error\n$stackTrace');
}),…eouts Avoid crashing the flutter tool when the analysis server subprocess exits prematurely or when the web debug connection times out. Fixes flutter#186962 Fixes flutter#186963
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Remove the redundant .catchError block on connectDebug future in attach, allowing connection errors (like TimeoutException) to propagate to asyncGuard and be handled by the central try-catch block in run. This makes the specific TimeoutException handler in run reachable and functional, avoiding duplicate logging and potential unhandled async crashes.
Roll Flutter from e03b91f1fe34 to f3a4b9897834 (63 revisions) flutter/flutter@e03b91f...f3a4b98 2026-05-26 47866232+chunhtai@users.noreply.github.com Update batch release doc to reflect latest workflow (flutter/flutter#186979) 2026-05-26 engine-flutter-autoroll@skia.org Roll Skia from 0442274cc696 to 27a819894f7c (5 revisions) (flutter/flutter#187094) 2026-05-26 bkonyi@google.com [Tool Robustness] Gracefully handle asynchronous subprocess crashes and connection timeouts (flutter/flutter#186964) 2026-05-26 bkonyi@google.com [pubspec] Bump Dart SDK constraint to ^3.13.0 (flutter/flutter#186957) 2026-05-26 engine-flutter-autoroll@skia.org Roll Dart SDK from 7eb54169841d to 00e625453c43 (1 revision) (flutter/flutter#187086) 2026-05-26 bdero@google.com [Impeller] Retire Y-coord-scale plumbing by flipping GLES at the vertex stage (flutter/flutter#186556) 2026-05-26 engine-flutter-autoroll@skia.org Roll Skia from f4f294bdf98d to 0442274cc696 (2 revisions) (flutter/flutter#187079) 2026-05-26 kevmoo@users.noreply.github.com [flutter_tools] Fix version cache poisoning from git environment variables (flutter/flutter#186595) 2026-05-26 bkonyi@google.com [Tool] Handle DTD connection failures gracefully in widget-preview (flutter/flutter#186952) 2026-05-25 engine-flutter-autoroll@skia.org Roll Skia from 9d1adb5f2427 to f4f294bdf98d (1 revision) (flutter/flutter#187056) 2026-05-25 engine-flutter-autoroll@skia.org Roll Skia from 4dd78179e6ec to 9d1adb5f2427 (1 revision) (flutter/flutter#187048) 2026-05-25 engine-flutter-autoroll@skia.org Roll Skia from 1f26101197bf to 4dd78179e6ec (4 revisions) (flutter/flutter#187044) 2026-05-24 engine-flutter-autoroll@skia.org Roll Skia from bbe9ccc2bdbf to 1f26101197bf (1 revision) (flutter/flutter#187016) 2026-05-24 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from nsgcNDlZOuweOvy3Q... to Itd2Jq_ZIABH2rW7B... (flutter/flutter#187032) 2026-05-23 engine-flutter-autoroll@skia.org Roll Dart SDK from 7e0f28eb5315 to 7eb54169841d (1 revision) (flutter/flutter#187005) 2026-05-23 engine-flutter-autoroll@skia.org Roll Dart SDK from 90e55fa88456 to 7e0f28eb5315 (1 revision) (flutter/flutter#186990) 2026-05-23 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from 6T6BY9PTftoG3vP_1... to nsgcNDlZOuweOvy3Q... (flutter/flutter#186984) 2026-05-23 chris@bracken.jp iOS] Migrate VSyncClient to a pure Obj-C implementation (#186166) (flutter/flutter#186935) 2026-05-23 30870216+gaaclarke@users.noreply.github.com Disables embedder_tests.cm for fuchsia (flutter/flutter#186969) 2026-05-23 engine-flutter-autoroll@skia.org Roll Dart SDK from b8414c46f6c7 to 90e55fa88456 (2 revisions) (flutter/flutter#186977) 2026-05-22 engine-flutter-autoroll@skia.org Roll Skia from 6fdb013d1953 to bbe9ccc2bdbf (1 revision) (flutter/flutter#186980) 2026-05-22 mdebbar@google.com [web] Fix cutoff text in WebParagraph (flutter/flutter#186819) 2026-05-22 1961493+harryterkelsen@users.noreply.github.com fix(web): Removes the iterative downscaling hack (flutter/flutter#186914) 2026-05-22 30870216+gaaclarke@users.noreply.github.com opts the linux embedder into sdf rendering (flutter/flutter#186909) 2026-05-22 engine-flutter-autoroll@skia.org Roll Skia from dae8778ca40d to 6fdb013d1953 (5 revisions) (flutter/flutter#186970) 2026-05-22 dacoharkes@google.com Fix hooks inputs outputs rebuilt (flutter/flutter#186701) 2026-05-22 30870216+gaaclarke@users.noreply.github.com adds linux impeller integration test for external textures (flutter/flutter#186759) 2026-05-22 kevmoo@users.noreply.github.com fix(flutter_tools): defensively catch DWDS unregistered service extension errors (flutter/flutter#186896) 2026-05-22 bdero@google.com [Impeller] Add golden harness support to the renderer test layer (flutter/flutter#186735) 2026-05-22 mdebbar@google.com [web] Remove image codecs from canvaskit_chromium (flutter/flutter#178133) 2026-05-22 30870216+gaaclarke@users.noreply.github.com opts all macos into wide gamut (flutter/flutter#186277) 2026-05-22 engine-flutter-autoroll@skia.org Roll Skia from 356185490a75 to dae8778ca40d (9 revisions) (flutter/flutter#186949) 2026-05-22 1598289+lukemmtt@users.noreply.github.com Filter out SwiftPM schemes when fetching schemes (flutter/flutter#186006) 2026-05-22 engine-flutter-autoroll@skia.org Roll Packages from 3754d04 to 69cf959 (1 revision) (flutter/flutter#186950) 2026-05-22 engine-flutter-autoroll@skia.org Roll Dart SDK from eca46bec956d to b8414c46f6c7 (2 revisions) (flutter/flutter#186944) 2026-05-22 30870216+gaaclarke@users.noreply.github.com Saves a DeviceHolderVK with the CommandPoolVK (flutter/flutter#186749) 2026-05-22 engine-flutter-autoroll@skia.org Roll Dart SDK from e0d509fd676e to eca46bec956d (1 revision) (flutter/flutter#186922) 2026-05-22 bkonyi@google.com [ Tool ] Stop generating widget preview scaffold under $TMP (flutter/flutter#186476) 2026-05-21 737941+loic-sharma@users.noreply.github.com Fix typo in StretchingOverscrollIndicator docs (flutter/flutter#186897) 2026-05-21 engine-flutter-autoroll@skia.org Roll Dart SDK from 28c7cb5a8e8d to e0d509fd676e (1 revision) (flutter/flutter#186903) 2026-05-21 jason-simmons@users.noreply.github.com Fix some issues in the integration between EmbedderExternalViewEmbedder and Impeller (flutter/flutter#184905) 2026-05-21 jason-simmons@users.noreply.github.com Fix a potential buffer overflow in the animated PNG decoder when parsing malformed fdAT chunks (flutter/flutter#186700) 2026-05-21 engine-flutter-autoroll@skia.org Roll Skia from 2ff20950975d to 356185490a75 (5 revisions) (flutter/flutter#186892) 2026-05-21 flar@google.com Add primitive shadows to rendering benchmark (flutter/flutter#186779) 2026-05-21 15619084+vashworth@users.noreply.github.com Move prefetchSwiftPackages to be per platform (flutter/flutter#186468) 2026-05-21 okorohelijah@google.com Upgrade iOS version (flutter/flutter#186889) ...
…r#11789) Roll Flutter from e03b91f1fe34 to f3a4b9897834 (63 revisions) flutter/flutter@e03b91f...f3a4b98 2026-05-26 47866232+chunhtai@users.noreply.github.com Update batch release doc to reflect latest workflow (flutter/flutter#186979) 2026-05-26 engine-flutter-autoroll@skia.org Roll Skia from 0442274cc696 to 27a819894f7c (5 revisions) (flutter/flutter#187094) 2026-05-26 bkonyi@google.com [Tool Robustness] Gracefully handle asynchronous subprocess crashes and connection timeouts (flutter/flutter#186964) 2026-05-26 bkonyi@google.com [pubspec] Bump Dart SDK constraint to ^3.13.0 (flutter/flutter#186957) 2026-05-26 engine-flutter-autoroll@skia.org Roll Dart SDK from 7eb54169841d to 00e625453c43 (1 revision) (flutter/flutter#187086) 2026-05-26 bdero@google.com [Impeller] Retire Y-coord-scale plumbing by flipping GLES at the vertex stage (flutter/flutter#186556) 2026-05-26 engine-flutter-autoroll@skia.org Roll Skia from f4f294bdf98d to 0442274cc696 (2 revisions) (flutter/flutter#187079) 2026-05-26 kevmoo@users.noreply.github.com [flutter_tools] Fix version cache poisoning from git environment variables (flutter/flutter#186595) 2026-05-26 bkonyi@google.com [Tool] Handle DTD connection failures gracefully in widget-preview (flutter/flutter#186952) 2026-05-25 engine-flutter-autoroll@skia.org Roll Skia from 9d1adb5f2427 to f4f294bdf98d (1 revision) (flutter/flutter#187056) 2026-05-25 engine-flutter-autoroll@skia.org Roll Skia from 4dd78179e6ec to 9d1adb5f2427 (1 revision) (flutter/flutter#187048) 2026-05-25 engine-flutter-autoroll@skia.org Roll Skia from 1f26101197bf to 4dd78179e6ec (4 revisions) (flutter/flutter#187044) 2026-05-24 engine-flutter-autoroll@skia.org Roll Skia from bbe9ccc2bdbf to 1f26101197bf (1 revision) (flutter/flutter#187016) 2026-05-24 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from nsgcNDlZOuweOvy3Q... to Itd2Jq_ZIABH2rW7B... (flutter/flutter#187032) 2026-05-23 engine-flutter-autoroll@skia.org Roll Dart SDK from 7e0f28eb5315 to 7eb54169841d (1 revision) (flutter/flutter#187005) 2026-05-23 engine-flutter-autoroll@skia.org Roll Dart SDK from 90e55fa88456 to 7e0f28eb5315 (1 revision) (flutter/flutter#186990) 2026-05-23 engine-flutter-autoroll@skia.org Roll Fuchsia Linux SDK from 6T6BY9PTftoG3vP_1... to nsgcNDlZOuweOvy3Q... (flutter/flutter#186984) 2026-05-23 chris@bracken.jp iOS] Migrate VSyncClient to a pure Obj-C implementation (#186166) (flutter/flutter#186935) 2026-05-23 30870216+gaaclarke@users.noreply.github.com Disables embedder_tests.cm for fuchsia (flutter/flutter#186969) 2026-05-23 engine-flutter-autoroll@skia.org Roll Dart SDK from b8414c46f6c7 to 90e55fa88456 (2 revisions) (flutter/flutter#186977) 2026-05-22 engine-flutter-autoroll@skia.org Roll Skia from 6fdb013d1953 to bbe9ccc2bdbf (1 revision) (flutter/flutter#186980) 2026-05-22 mdebbar@google.com [web] Fix cutoff text in WebParagraph (flutter/flutter#186819) 2026-05-22 1961493+harryterkelsen@users.noreply.github.com fix(web): Removes the iterative downscaling hack (flutter/flutter#186914) 2026-05-22 30870216+gaaclarke@users.noreply.github.com opts the linux embedder into sdf rendering (flutter/flutter#186909) 2026-05-22 engine-flutter-autoroll@skia.org Roll Skia from dae8778ca40d to 6fdb013d1953 (5 revisions) (flutter/flutter#186970) 2026-05-22 dacoharkes@google.com Fix hooks inputs outputs rebuilt (flutter/flutter#186701) 2026-05-22 30870216+gaaclarke@users.noreply.github.com adds linux impeller integration test for external textures (flutter/flutter#186759) 2026-05-22 kevmoo@users.noreply.github.com fix(flutter_tools): defensively catch DWDS unregistered service extension errors (flutter/flutter#186896) 2026-05-22 bdero@google.com [Impeller] Add golden harness support to the renderer test layer (flutter/flutter#186735) 2026-05-22 mdebbar@google.com [web] Remove image codecs from canvaskit_chromium (flutter/flutter#178133) 2026-05-22 30870216+gaaclarke@users.noreply.github.com opts all macos into wide gamut (flutter/flutter#186277) 2026-05-22 engine-flutter-autoroll@skia.org Roll Skia from 356185490a75 to dae8778ca40d (9 revisions) (flutter/flutter#186949) 2026-05-22 1598289+lukemmtt@users.noreply.github.com Filter out SwiftPM schemes when fetching schemes (flutter/flutter#186006) 2026-05-22 engine-flutter-autoroll@skia.org Roll Packages from 3754d04 to 69cf959 (1 revision) (flutter/flutter#186950) 2026-05-22 engine-flutter-autoroll@skia.org Roll Dart SDK from eca46bec956d to b8414c46f6c7 (2 revisions) (flutter/flutter#186944) 2026-05-22 30870216+gaaclarke@users.noreply.github.com Saves a DeviceHolderVK with the CommandPoolVK (flutter/flutter#186749) 2026-05-22 engine-flutter-autoroll@skia.org Roll Dart SDK from e0d509fd676e to eca46bec956d (1 revision) (flutter/flutter#186922) 2026-05-22 bkonyi@google.com [ Tool ] Stop generating widget preview scaffold under $TMP (flutter/flutter#186476) 2026-05-21 737941+loic-sharma@users.noreply.github.com Fix typo in StretchingOverscrollIndicator docs (flutter/flutter#186897) 2026-05-21 engine-flutter-autoroll@skia.org Roll Dart SDK from 28c7cb5a8e8d to e0d509fd676e (1 revision) (flutter/flutter#186903) 2026-05-21 jason-simmons@users.noreply.github.com Fix some issues in the integration between EmbedderExternalViewEmbedder and Impeller (flutter/flutter#184905) 2026-05-21 jason-simmons@users.noreply.github.com Fix a potential buffer overflow in the animated PNG decoder when parsing malformed fdAT chunks (flutter/flutter#186700) 2026-05-21 engine-flutter-autoroll@skia.org Roll Skia from 2ff20950975d to 356185490a75 (5 revisions) (flutter/flutter#186892) 2026-05-21 flar@google.com Add primitive shadows to rendering benchmark (flutter/flutter#186779) 2026-05-21 15619084+vashworth@users.noreply.github.com Move prefetchSwiftPackages to be per platform (flutter/flutter#186468) 2026-05-21 okorohelijah@google.com Upgrade iOS version (flutter/flutter#186889) ...
Avoid crashing the flutter tool when the analysis server subprocess exits prematurely (e.g. with 255) or when the web debug connection times out.
For the analysis server, we introduce a private _AnalysisServerExitException and map it to a clean ToolExit when awaiting the analysis.
For the web runner, we attach a .catchError handler to the connectDebug future to handle connection timeouts, printing a clear error and exiting via ToolExit instead of raising an unhandled async error.
Fixes #186962
Fixes #186963