[flutter_tools] Prevent interactive device selection in machine mode#188267
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Fixes a crash when running `flutter run --machine` (or other commands in machine mode) when multiple devices are connected and no device is specified. Previously, if multiple devices were connected, the tool would attempt to prompt the user interactively to select a device, even in machine mode. This interactive prompt listens to `stdin` (via a broadcast stream wrapper). Since `stdin` is a single-subscription stream, once it has been listened to by the prompt, it cannot be listened to again. When the machine daemon later attempts to listen to `stdin` to receive JSON-RPC commands, it throws a `StateError: Bad state: Stream has already been listened to.` and crashes. This fix introduces a `canPrompt` flag to device discovery and selection methods (defaulting to `!outputMachineFormat` in `FlutterCommand`), which disables interactive prompting when running in machine mode. Instead, the tool will print the available devices and exit gracefully, which is the correct behavior for machine-to-machine communication when a required parameter is missing. Fixes flutter#175948
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This pull request introduces a canPrompt parameter to findAllTargetDevices and its helper methods to control interactive device selection prompting, defaulting to false when machine format output is enabled. Unit tests are added to verify these interactions. The reviewer suggested defensively checking if argResults is non-null in outputMachineFormat to prevent potential null pointer errors during early command initialization or in tests.
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autosubmit label was removed for flutter/flutter/188267, because - The status or check suite Google testing 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/188267, because - The status or check suite Google testing 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/188267, because The base commit of the PR is older than 7 days and can not be merged. Please merge the latest changes from the main into this branch and resubmit the PR. |
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…12169) Manual roll Flutter from 91939cc4db78 to dc2a8703e12b (50 revisions) Manual roll requested by [email protected] flutter/flutter@91939cc...dc2a870 2026-07-09 [email protected] [ios,macos] Update swiftc.py flags to match swiftc (flutter/flutter#189174) 2026-07-09 [email protected] [AGP 9] Update Warn Version to AGP 9+ (flutter/flutter#189109) 2026-07-09 [email protected] Sync CHANGELOG.md from stable (flutter/flutter#189203) 2026-07-09 [email protected] [web] Roll Chrome to 145 (framework) (flutter/flutter#182861) 2026-07-09 [email protected] Roll Packages from 52d84d6 to 20928d5 (6 revisions) (flutter/flutter#189194) 2026-07-09 [email protected] [web] Avoid absolute positioning for base CanvasKit canvas (flutter/flutter#188337) 2026-07-09 [email protected] Roll Dart SDK from cdb7217e65aa to a11fb7ed40a5 (6 revisions) (flutter/flutter#189195) 2026-07-09 [email protected] Fix dereference of nullptr in the moved-to-rect signal in the Linux embedder (flutter/flutter#189152) 2026-07-09 [email protected] Fix data for design packages (flutter/flutter#189140) 2026-07-09 [email protected] Roll Skia from 7b42d1251d54 to ab3a7b98c94d (2 revisions) (flutter/flutter#189181) 2026-07-09 [email protected] Roll Skia from 05d9d214e0b7 to 7b42d1251d54 (2 revisions) (flutter/flutter#189175) 2026-07-09 [email protected] Roll Skia from 542c8bdd7f4f to 05d9d214e0b7 (4 revisions) (flutter/flutter#189169) 2026-07-09 [email protected] UberSDF rect handling for thin (line-like) rectangles (flutter/flutter#188821) 2026-07-09 [email protected] Roll Skia from dd572c07f63c to 542c8bdd7f4f (4 revisions) (flutter/flutter#189160) 2026-07-09 [email protected] [flutter_tools] Fix hot restart for WASM web builds (flutter/flutter#187898) 2026-07-08 [email protected] Split FlViewRenderer into OpenGL and software backends (flutter/flutter#188824) 2026-07-08 [email protected] Promote android_hardware_smoke_tests out of bringup in CI (flutter/flutter#189081) 2026-07-08 [email protected] Roll Skia from 8df24be66531 to dd572c07f63c (4 revisions) (flutter/flutter#189150) 2026-07-08 [email protected] Expose LinuxWindowRegistrar on _window_linux.dart in order to better support out of tree LinuxWindowingOwners (flutter/flutter#188917) 2026-07-08 [email protected] Roll pub packages (flutter/flutter#189149) 2026-07-08 [email protected] fix(ci): harden some workflows (flutter/flutter#189087) 2026-07-08 [email protected] Roll Skia from 51a62da33da0 to 8df24be66531 (1 revision) (flutter/flutter#189139) 2026-07-08 [email protected] Roll Dart SDK to Dart 3.13 beta3 (flutter/flutter#189122) 2026-07-08 [email protected] [flutter_tools] Don't crash on non-UTF-8 plugin pubspec.yaml (flutter/flutter#188976) 2026-07-08 [email protected] [flutter_tools] Watch transitive #include headers for FragmentProgram hot reload (flutter/flutter#187945) 2026-07-08 [email protected] Roll Skia from 040d9f55de00 to 51a62da33da0 (1 revision) (flutter/flutter#189135) 2026-07-08 [email protected] Roll Packages from 92525f5 to 52d84d6 (7 revisions) (flutter/flutter#189134) 2026-07-08 [email protected] [flutter_tools] Forcefully kill hung subprocesses 5 seconds after timeout (flutter/flutter#187178) 2026-07-08 [email protected] Expose the app's build name and number as compile-time constants (flutter/flutter#187935) 2026-07-08 [email protected] Roll Skia from 1ff92f879815 to 040d9f55de00 (1 revision) (flutter/flutter#189131) 2026-07-08 [email protected] Roll Skia from 6137414bef5c to 1ff92f879815 (6 revisions) (flutter/flutter#189126) 2026-07-08 [email protected] [test cross imports] More test/rendering + flutter_test/test fixes (flutter/flutter#188954) 2026-07-08 [email protected] engine: explain why each candidate build was skipped in Flutter web loader (flutter/flutter#186254) 2026-07-08 [email protected] vscode: add missing unicode.h (flutter/flutter#189102) 2026-07-08 [email protected] Roll Fuchsia Linux SDK from 7RjQJBW3m-3Jl-7jr... to QcRFUtvCw2EobfJ8s... (flutter/flutter#189104) 2026-07-08 [email protected] Roll Skia from 075fbe4778d9 to 6137414bef5c (10 revisions) (flutter/flutter#189106) 2026-07-08 [email protected] engine: warn on WASM load failure when not crossOriginIsolated (flutter/flutter#186252) 2026-07-08 [email protected] Roll Dart SDK from c9bccc09e733 to db2155f56bf3 (2 revisions) (flutter/flutter#189105) 2026-07-08 [email protected] [flutter_tools] Prevent interactive device selection in machine mode (flutter/flutter#188267) 2026-07-08 [email protected] [flutter_tools] Fix wireless ADB device discovery when serial contains spaces (flutter/flutter#187943) 2026-07-07 [email protected] [web] Fix grouped autofill on iOS Chrome (flutter/flutter#187459) 2026-07-07 [email protected] Fix TextSelectionOverlay crash when layout is degenerate (flutter/flutter#188672) 2026-07-07 [email protected] [flutter_tools] Provision Android NDK in the main Gradle invocation (flutter/flutter#186337) 2026-07-07 [email protected] Android_hardware_smoke_test: Migrate to AGP 9 (flutter/flutter#189082) ...
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Fixes a crash when running
flutter run --machine(or other commands in machine mode) when multiple devices are connected and no device is specified.Previously, if multiple devices were connected, the tool would attempt to prompt the user interactively to select a device, even in machine mode. This interactive prompt listens to
stdin(via a broadcast stream wrapper). Sincestdinis a single-subscription stream, once it has been listened to by the prompt, it cannot be listened to again. When the machine daemon later attempts to listen tostdinto receive JSON-RPC commands, it throws aStateError: Bad state: Stream has already been listened to.and crashes.This fix introduces a
canPromptflag to device discovery and selection methods (defaulting to!outputMachineFormatinFlutterCommand), which disables interactive prompting when running in machine mode. Instead, the tool will print the available devices and exit gracefully, which is the correct behavior for machine-to-machine communication when a required parameter is missing.Fixes #175948