[amplify_flutter] Support using `--wasm` flutter cli argument.

[asaarnak]

Because amplify_flutter is using Platform.isAndroid.

This is thrown: Unsupported operation: Platform._operatingSystem

Line: call $Platform.isAndroid

  (func $new AmplifyClassImpl (;33855;) (result (ref $AmplifyClassImpl))
    block $label1
      block $label0
        call $Platform.isAndroid implicit getter
        br_if $label0
        call $Platform.isIOS implicit getter
        i32.eqz
        br_if $label1
      end $label0
      call $AmplifyHybridImpl
      return
    end $label1
    call $AmplifyClassImpl.protected
    return
  )

The pub.dev suggests removing dart:io import from:
package:amplify_flutter/amplify_flutter.dart
package:amplify_flutter/src/amplify_impl.dart

[ekjotmultani]

Hi @asaarnak, thank you for raising this issue, along with a PR! Please see the discussion on that thread, we appreciate community contribution! We will track this as a feature request

[asaarnak]

Hi @ekjotmultani.
I added an comment under the PR.
Thanks.

I found the same issue with other packages while testing.
The amplify_auth_cognito has same errors.

[asaarnak]

@tyllark
After these commits the application is starting and loading first page.

But when i try to login i get some errors about worker on this line:

await Amplify.Auth.signIn(
  username: email,
  options: const SignInOptions(
    pluginOptions: CognitoSignInPluginOptions(
      authFlowType: AuthenticationFlowType.customAuthWithoutSrp,
    ),
  ),
);

Its looking for a file workers.debug.dart.js but can't find it, also when running with --release tag then its looking for a file workers.release.dart.js and also it's looking it from packages/amplify_auth_cognito_dart and also from test/packages/amplify_auth_cognito_dart directory.

http://localhost:41167/packages/amplify_auth_cognito_dart/src/workers/workers.js
http://localhost:41167/packages/amplify_auth_cognito_dart/src/workers/workers.debug.dart.js
http://localhost:41167/test/packages/amplify_auth_cognito_dart/src/workers/workers.debug.dart.js

main.dart.mjs:66 DEBUG | SignInStateMachine | Device secrets not present for user: user@gmail.com
main.dart.mjs:66 FINE: 2025-09-15 14:57:51.187: AWS.Amplify.AmplifyAuthCognito.SignInStateMachine: Device secrets not present for user: user@gmail.com
main.dart.mjs:66 FINE: 2025-09-15 14:57:51.228: AWS.ASFContextDataProvider.ASFWorker: Spawning worker at packages/amplify_auth_cognito_dart/src/workers/workers.js
Refused to execute script from 'http://localhost:43001/packages/amplify_auth_cognito_dart/src/workers/workers.js' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled.
:43001/#/login:1 Refused to execute script from 'http://localhost:43001/packages/amplify_auth_cognito_dart/src/workers/workers.js' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled.
main.dart.mjs:66 FINE: 2025-09-15 14:57:51.241: AWS.ASFContextDataProvider.ASFWorker: Error initializing worker: WorkerBeeExceptionImpl {
main.dart.mjs:66   error=An unknown error occurred,
main.dart.mjs:66 }
main.dart.mjs:66 FINE: 2025-09-15 14:57:51.243: AWS.ASFContextDataProvider.ASFWorker: Spawning worker at packages/amplify_auth_cognito_dart/src/workers/workers.debug.dart.js
Refused to execute script from 'http://localhost:43001/packages/amplify_auth_cognito_dart/src/workers/workers.debug.dart.js' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled.
:43001/#/login:1 Refused to execute script from 'http://localhost:43001/packages/amplify_auth_cognito_dart/src/workers/workers.debug.dart.js' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled.
main.dart.mjs:66 FINE: 2025-09-15 14:57:51.262: AWS.ASFContextDataProvider.ASFWorker: Error initializing worker: WorkerBeeExceptionImpl {
main.dart.mjs:66   error=An unknown error occurred,
main.dart.mjs:66 }
main.dart.mjs:66 FINE: 2025-09-15 14:57:51.264: AWS.ASFContextDataProvider.ASFWorker: Spawning worker at http://localhost:43001/test/packages/amplify_auth_cognito_dart/src/workers/workers.debug.dart.js
Refused to execute script from 'http://localhost:43001/test/packages/amplify_auth_cognito_dart/src/workers/workers.debug.dart.js' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled.
:43001/#/login:1 Refused to execute script from 'http://localhost:43001/test/packages/amplify_auth_cognito_dart/src/workers/workers.debug.dart.js' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled.
main.dart.mjs:66 FINE: 2025-09-15 14:57:51.275: AWS.ASFContextDataProvider.ASFWorker: Error initializing worker: WorkerBeeExceptionImpl {
main.dart.mjs:66   error=An unknown error occurred,
main.dart.mjs:66 }
main.dart.mjs:66 FINE: 2025-09-15 14:57:51.277: AWS.ASFContextDataProvider.ASFWorker: Error in worker: WorkerBeeExceptionImpl {
main.dart.mjs:66   error=Could not launch web worker.,
main.dart.mjs:66   stackTrace=main.dart.wasm 1:3043195  module0._awaitHelper closure at org-dartlang-sdk:///dart-sdk/lib/_internal/wasm/lib/async_patch.dart:107:14
main.dart.mjs:66 main.dart.wasm 1:3043275  module0.closure wrapper at org-dartlang-sdk:///dart-sdk/lib/_internal/wasm/lib/async_patch.dart:107:14 trampoline
main.dart.mjs:66 main.dart.wasm 1:4853750  module0.StackZoneSpecification._registerBinaryCallback closure at file:///home/a/.pub-cache/hosted/pub.dev/stack_trace-1.12.1/lib/src/stack_zone_specification.dart:138:36
main.dart.mjs:66 main.dart.wasm 1:4853973  module0.closure wrapper at file:///home/a/.pub-cache/hosted/pub.dev/stack_trace-1.12.1/lib/src/stack_zone_specification.dart:138:36 trampoline
main.dart.mjs:66 main.dart.wasm 1:4854082  module0.StackZoneSpecification._run
main.dart.mjs:66 main.dart.wasm 1:4853653  module0.StackZoneSpecification._registerBinaryCallback closure at file:///home/a/.pub-cache/hosted/pub.dev/stack_trace-1.12.1/lib/src/stack_zone_specification.dart:138:15
main.dart.mjs:66 main.dart.wasm 1:4853946  module0.closure wrapper at file:///home/a/.pub-cache/hosted/pub.dev/stack_trace-1.12.1/lib/src/stack_zone_specification.dart:138:15 trampoline
main.dart.mjs:66 ===== asynchronous gap ===========================
main.dart.mjs:66 main.dart.wasm 1:3443620  module0._CustomZone.registerCallback
main.dart.mjs:66 main.dart.wasm 1:3443261  module0._CustomZone.bindCallbackGuarded
main.dart.mjs:66 main.dart.wasm 1:3032047  module0._rootScheduleMicrotask
main.dart.mjs:66 main.dart.wasm 1:3038642  module0._rootScheduleMicrotask tear-off trampoline
main.dart.mjs:66 ===== asynchronous gap ===========================
main.dart.mjs:66 main.dart.wasm 1:3444214  module0._CustomZone.registerBinaryCallback
main.dart.mjs:66 main.dart.wasm 1:3041804  module0._registerErrorHandler
main.dart.mjs:66 main.dart.wasm 1:3041585  module0._Future.then
main.dart.mjs:66 main.dart.wasm 1:3031522  module0._awaitHelper
main.dart.mjs:66 ===== asynchronous gap ===========================
main.dart.mjs:66 main.dart.wasm 1:3444214  module0._CustomZone.registerBinaryCallback
main.dart.mjs:66 main.dart.wasm 1:3041804  module0._registerErrorHandler
main.dart.mjs:66 main.dart.wasm 1:3041585  module0._Future.then
main.dart.mjs:66 main.dart.wasm 1:3031522  module0._awaitHelper
main.dart.mjs:66 ===== asynchronous gap ===========================
main.dart.mjs:66 main.dart.wasm 1:3444214  module0._CustomZone.registerBinaryCallback
main.dart.mjs:66 main.dart.wasm 1:3041804  module0._registerErrorHandler
main.dart.mjs:66 main.dart.wasm 1:3041585  module0._Future.then
main.dart.mjs:66 main.dart.wasm 1:3031522  module0._awaitHelper
main.dart.mjs:66 ,
main.dart.mjs:66 }
WebGL: CONTEXT_LOST_WEBGL: loseContext: context lost
:43001/#/login:1 WebGL: CONTEXT_LOST_WEBGL: loseContext: context lost