[local_auth] Convert Android to new Pigeon suspend support by stuartmorgan-g · Pull Request #12894 · flutter/packages

stuartmorgan-g · 2026-09-17T14:14:19Z

Switches the async authenticate method from the old callback system to Pigeon's new suspend support. Because the underlying SDK doesn't have a suspend-style method currently, the plugin bridges the existing intrenal callback to a suspend coroutine.

This will simplify later conversion to JNI-backed Pigeon, and also simplifies unit tests.

Part of flutter/flutter#192417

Pre-Review Checklist

Regular contributors who have demonstrated familiarity with the repository guidelines only need to comment if the PR is not auto-exempted by repo tooling. ↩ ↩²

Switches the async authenticat method from the old callback system to Pigeon's new `suspend` support. Because the underlying SDK doesn't have a `suspend`-style method currently, the plugin bridges the existing intrenal callback to a `suspend` coroutine. This will simplify later conversion to JNI-backed Pigeon, and also simplifies unit tests. Part of flutter/flutter#192417

gemini-code-assist

Code Review

This pull request updates the internal platform API of the Android local authentication plugin from callbacks to Kotlin coroutines (suspend functions), updating the Pigeon-generated messages and modifying the corresponding unit tests to run within runTest. A review comment identifies a potential issue in createAuthCompletionHandler where the suspended authenticate coroutine could hang indefinitely if stopAuthentication() is called, and suggests using a local AtomicBoolean to guarantee the continuation is resumed exactly once.

gemini-code-assist · 2026-09-17T14:15:52Z

  internal fun createAuthCompletionHandler(
-      callback: (Result<AuthResult>) -> Unit
+      continuation: Continuation<AuthResult>
  ): (AuthResult) -> Unit {
-    return { authResult -> onAuthenticationCompleted(callback, authResult) }
+    return { authResult ->
+      if (authInProgress.compareAndSet(true, false)) {
+        continuation.resume(authResult)
+      }
+    }
  }


If stopAuthentication() is called, it sets authInProgress to false and cancels the authentication. This asynchronously triggers onAuthenticationError in AuthenticationHelper, which invokes this completion handler.\n\nHowever, because authInProgress has already been set to false by stopAuthentication(), the check authInProgress.compareAndSet(true, false) will fail, and continuation.resume(authResult) will never be called. This causes the suspended authenticate coroutine to hang indefinitely, leaking resources and preventing the Dart Future from completing.\n\nUsing a local AtomicBoolean to ensure the continuation is resumed exactly once, while safely attempting to clear the global authInProgress state, resolves this hang and avoids potential race conditions with subsequent authentication attempts.

internal fun createAuthCompletionHandler( continuation: Continuation<AuthResult> ): (AuthResult) -> Unit { val resumed = AtomicBoolean(false) return { authResult -> if (resumed.compareAndSet(false, true)) { authInProgress.compareAndSet(true, false) continuation.resume(authResult) } } }

This was bothering me when I was touching the code as well, so I had checked the history and it's pretty much always worked this way so I let it go. But it does seem like it if works it's because it happens not to actually be async, which doesn't seem like a good thing to rely on. I updated the PR to remove the authInProgress.set(false) line from cancel, so that it will be set to false by the callback actually triggering instead. (I verified locally with a synthetic timed cancel that this works as expected.)

stuartmorgan-g · 2026-09-17T14:15:55Z

The test changes here were Gemini-authored, but (with the caveat that I'm not familiar with the specific test utilities involved here) looked good to me, and had the simplifications of directly using returned values that I was expecting from the refactor.

mboetger

Sorry I didn't get to this before your last day - happy to take over from here if you want. Just let me know.

stuartmorgan · 2026-10-13T17:01:41Z

@mboetger You'll need to do a CLA override on this; the automagic group stuff has updated such that my old @google.com address fails the CLA now. We've run into this before, and I always just put something like "Author was employed at Google at time the PR was opened".

mboetger · 2026-10-13T22:41:44Z

@mboetger You'll need to do a CLA override on this; the automagic group stuff has updated such that my old @google.com address fails the CLA now. We've run into this before, and I always just put something like "Author was employed at Google at time the PR was opened".

Done.

Roll Packages from a1ed23c to da40eaf (33 revisions) flutter/packages@a1ed23c...da40eaf 2026-10-15 [email protected] [pigeon]add support for sealed classes in native interop (flutter/packages#13175) 2026-10-15 [email protected] [pigeon] Replace full JNI bindings with stubs for API classes that aren't needed (flutter/packages#13173) 2026-10-14 [email protected] [material_ui] Fix self-comparison and assert bugs in semantics_tester (flutter/packages#12722) 2026-10-14 [email protected] [camera_avfoundation] Replace the deprecated 'videoOrientation' with 'videoRotationAngle' on iOS 17+ (flutter/packages#13247) 2026-10-14 [email protected] [material_ui] Fix GridTile crash when the incoming constraints are unbounded (flutter/packages#12586) 2026-10-14 [email protected] [in_app_purchase_storekit] Remove unused and deprecated "SKDownload" hosted content (flutter/packages#13222) 2026-10-14 [email protected] [material_ui] Add supportingTextPadding to InputDecorator (flutter/packages#12769) 2026-10-14 [email protected] [vector_graphics_codec] Add support for encoding and decoding paint blur commands (flutter/packages#13148) 2026-10-14 [email protected] [go_router] Fix redirect zone async error handling (flutter/packages#12836) 2026-10-14 [email protected] Sync release-go_router-18.1.0 to main (flutter/packages#13260) 2026-10-14 [email protected] Sync release-cupertino_ui-1.1.3 to main (flutter/packages#13258) 2026-10-14 [email protected] [material_ui] add enableInlinePrediction parameter to TextFormField (flutter/packages#12793) 2026-10-14 [email protected] Sync release-material_ui-1.7.0 to main (flutter/packages#13259) 2026-10-14 [email protected] [material_ui] Add the Material shapes. (flutter/packages#12771) 2026-10-14 [email protected] [material_ui] Add tertiary tap callbacks to InkResponse and InkWell (flutter/packages#12676) 2026-10-14 [email protected] Roll Flutter from 4249ccb to 426be96 (44 revisions) (flutter/packages#13256) 2026-10-14 [email protected] [material_ui] fixes expanded state in the a11y_assessment home page dropdown (flutter/packages#13219) 2026-10-14 [email protected] [VPAT] Fix semantics in a11y_assessments drawer, radio, and rail demos (flutter/packages#13159) 2026-10-14 [email protected] [google_maps_flutter] Add onPointOfInterestTap (flutter/packages#11872) 2026-10-14 [email protected] [go_router] Fix shell route key collisions and dynamic branch updates (flutter/packages#12549) 2026-10-14 [email protected] Manual roll Flutter from d03768e to 4249ccb (158 revisions) (flutter/packages#13220) 2026-10-14 [email protected] [image_picker_ios] Require Flutter 3.47 / iOS 15 and drop deprecated kUTType code paths (flutter/packages#13224) 2026-10-13 [email protected] [in_app_purchase_storekit] Fixes Storekit 2 flaky tests (flutter/packages#13213) 2026-10-13 [email protected] [local_auth] Convert Android to new Pigeon suspend support (flutter/packages#12894) 2026-10-13 [email protected] [material_ui] Add enabled parameter to DropdownButtonFormField (flutter/packages#12610) 2026-10-13 [email protected] [go_router] Link ShellRoute docs to StatefulShellRoute (flutter/packages#13120) 2026-10-13 [email protected] FadeForwards page transition performance (flutter/packages#13161) 2026-10-13 [email protected] [in_app_purchase_android] Guard async billing callbacks against duplicate listener responses (flutter/packages#12640) 2026-10-13 [email protected] [google_sign_in] Remove the Objective-C exception catcher (flutter/packages#13156) 2026-10-13 [email protected] [camera_avfoundation] Remove availability checks below the package minimum iOS 13 (flutter/packages#13214) 2026-10-13 [email protected] [google_maps_flutter_ios] Remove iOS 14 availability check from example UI tests (flutter/packages#13218) 2026-10-13 [email protected] [google_sign_in] Convert implementation to Kotlin (flutter/packages#13005) 2026-10-13 [email protected] [image_picker_ios] PR 2/5 Add a PHImageManager image-data seam and migrate plugin native tests to Swift Testing (flutter/packages#13079) 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-flutter-autoroll Please CC [email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Flutter: 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: ...

stuartmorgan-g requested a review from mboetger September 17, 2026 14:14

flutter-dashboard Bot added the CICD Run CI/CD label Sep 17, 2026

github-actions Bot added p: local_auth platform-android labels Sep 17, 2026

gemini-code-assist Bot reviewed Sep 17, 2026

View reviewed changes

stuartmorgan-g added 2 commits September 17, 2026 10:44

Don't set auth to false when canceling

8d0c38c

Merge branch 'main' into kotlin-local-auth-part-3-async

490bd42

anilcancakir mentioned this pull request Sep 27, 2026

[local_auth] Keep a stopped sticky prompt from reappearing on Android #13039

Closed

10 of 11 tasks

mboetger approved these changes Oct 12, 2026

View reviewed changes

Merge branch 'main' into kotlin-local-auth-part-3-async

5c382f5

mboetger added the autosubmit Merge PR when tree becomes green via auto submit App label Oct 13, 2026

auto-submit Bot merged commit ca5b2e5 into flutter:main Oct 13, 2026
13 checks passed

This was referenced Oct 14, 2026

Roll Packages from a1ed23c8f760 to ac2db9cfeaf6 (12 revisions) flutter/flutter#194387

Closed

Roll Packages from a1ed23c8f760 to da40eaf4548a (33 revisions) flutter/flutter#194459

Merged

Navigation Menu

Repository navigation

[local_auth] Convert Android to new Pigeon suspend support - #12894

[local_auth] Convert Android to new Pigeon suspend support#12894
auto-submit[bot] merged 4 commits into
flutter:mainfrom
stuartmorgan-g:kotlin-local-auth-part-3-async

stuartmorgan-g commented Sep 17, 2026 •

edited

Loading

Uh oh!

gemini-code-assist Bot left a comment

Uh oh!

gemini-code-assist Bot Sep 17, 2026

Uh oh!

stuartmorgan-g Sep 17, 2026

Uh oh!

stuartmorgan-g commented Sep 17, 2026

Uh oh!

mboetger left a comment

Uh oh!

stuartmorgan commented Oct 13, 2026

Uh oh!

mboetger commented Oct 13, 2026

Uh oh!

Uh oh!

Reviewers

Uh oh!

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

Conversation

stuartmorgan-g commented Sep 17, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Pre-Review Checklist

Footnotes

Uh oh!

gemini-code-assist Bot left a comment

Choose a reason for hiding this comment

Code Review

Uh oh!

gemini-code-assist Bot Sep 17, 2026

Choose a reason for hiding this comment

Uh oh!

stuartmorgan-g Sep 17, 2026

Choose a reason for hiding this comment

Uh oh!

stuartmorgan-g commented Sep 17, 2026

Uh oh!

mboetger left a comment

Choose a reason for hiding this comment

Uh oh!

stuartmorgan commented Oct 13, 2026

Uh oh!

mboetger commented Oct 13, 2026

Uh oh!

Uh oh!

Reviewers

Uh oh!

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

stuartmorgan-g commented Sep 17, 2026 •

edited

Loading