Cannot find suitable method System.Enum.Parse(2 parameters)

[Susko3]

Seen in the wild at ppy/osu#20614 (this app is using monoandroid10.0).

Seems to be caused by trimming/optimization that is done on Android Release builds.
The method Enum.Parse<TEnum>(string, bool) (fetched by AutoMapper via reflection) seems to be missing.

Version: 12.0.0

Expected behavior

Using AutoMapper shouldn't crash the app.

Actual behavior

Using any part of AutoMapper crashes the app with the following stack trace.

10-22 22:51:30.070 24694 24694 E AndroidRuntime: FATAL EXCEPTION: main
10-22 22:51:30.070 24694 24694 E AndroidRuntime: Process: com.companyname.app1, PID: 24694
10-22 22:51:30.070 24694 24694 E AndroidRuntime: android.runtime.JavaProxyThrowable: System.TypeInitializationException: The type initializer for 'AutoMapper.Internal.Mappers.StringToEnumMapper' threw an exception. ---> System.ArgumentOutOfRangeException: Cannot find suitable method System.Enum.Parse(2 parameters).
10-22 22:51:30.070 24694 24694 E AndroidRuntime: Parameter name: methodName
10-22 22:51:30.070 24694 24694 E AndroidRuntime:   at AutoMapper.Internal.TypeExtensions.StaticGenericMethod (System.Type type, System.String methodName, System.Int32 parametersCount) [0x0004e] in <f0f2d41eebaf41da82f0b54e1380e562>:0
10-22 22:51:30.070 24694 24694 E AndroidRuntime:   at AutoMapper.Internal.Mappers.StringToEnumMapper..cctor () [0x00019] in <f0f2d41eebaf41da82f0b54e1380e562>:0
10-22 22:51:30.070 24694 24694 E AndroidRuntime:    --- End of inner exception stack trace ---
10-22 22:51:30.070 24694 24694 E AndroidRuntime:   at AutoMapper.Internal.Mappers.MapperRegistry.Mappers () [0x00049] in <f0f2d41eebaf41da82f0b54e1380e562>:0
10-22 22:51:30.070 24694 24694 E AndroidRuntime:   at AutoMapper.MapperConfigurationExpression..ctor () [0x00040] in <f0f2d41eebaf41da82f0b54e1380e562>:0
10-22 22:51:30.070 24694 24694 E AndroidRuntime:   at AutoMapper.MapperConfiguration.Build (System.Action`1[T] configure) [0x00000] in <f0f2d41eebaf41da82f0b54e1380e562>:0
10-22 22:51:30.070 24694 24694 E AndroidRuntime:   at AutoMapper.MapperConfiguration..ctor (System.Action`1[T] configure) [0x00000] in <f0f2d41eebaf41da82f0b54e1380e562>:0
10-22 22:51:30.070 24694 24694 E AndroidRuntime:   at App1.MainActivity.OnCreate (Android.OS.Bundle savedInstanceState) [0x00022] in <9ca4390c120b485c93ba97c56d55de2c>:0
10-22 22:51:30.070 24694 24694 E AndroidRuntime:   at Android.App.Activity.n_OnCreate_Landroid_os_Bundle_ (System.IntPtr jnienv, System.IntPtr native__this, System.IntPtr native_savedInstanceState) [0x0000f] in <95707276dab64377aff41df0eecbc657>:0
10-22 22:51:30.070 24694 24694 E AndroidRuntime:   at (wrapper dynamic-method) Android.Runtime.DynamicMethodNameCounter.1(intptr,intptr,intptr)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at crc64a7a6b04b89628087.MainActivity.n_onCreate(Native Method)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at crc64a7a6b04b89628087.MainActivity.onCreate(MainActivity.java:38)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at android.app.Activity.performCreate(Activity.java:8151)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at android.app.Activity.performCreate(Activity.java:8135)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1309)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3704)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3903)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2328)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at android.os.Handler.dispatchMessage(Handler.java:106)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at android.os.Looper.loop(Looper.java:255)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at android.app.ActivityThread.main(ActivityThread.java:8212)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at java.lang.reflect.Method.invoke(Native Method)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:632)
10-22 22:51:30.070 24694 24694 E AndroidRuntime:        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1049)

Steps to reproduce

1. Create a new Android Xamarin project
2. Add AutoMapper 12.0.0 nuget package
3. Add the following to MainActivity.cs:

protected override void OnCreate(Bundle savedInstanceState)
{
    base.OnCreate(savedInstanceState);
    Xamarin.Essentials.Platform.Init(this, savedInstanceState);
    // Set our view from the "main" layout resource
    SetContentView(Resource.Layout.activity_main);

+    var mapper = new AutoMapper.MapperConfiguration(c => { }).CreateMapper();
+    Title = mapper.ToString();
}

4. Run the project in Release on a device

Steps to fix this issue (any will work)

• downgrade to AutoMapper 11.0.1
• build in Debug configuration
• apply this diff

protected override void OnCreate(Bundle savedInstanceState)
{
    base.OnCreate(savedInstanceState);
    Xamarin.Essentials.Platform.Init(this, savedInstanceState);
    // Set our view from the "main" layout resource
    SetContentView(Resource.Layout.activity_main);

+    var t = Enum.Parse<InputSourceType>("1", true);
+    Title = t.ToString();

    var mapper = new AutoMapper.MapperConfiguration(c => { }).CreateMapper();
    Title = mapper.ToString();
}

[lbargaoanu]

You need to configure your project to not trim the missing method.

[Susko3]

Hmm, I would expect the library to configure / signal to the compiler what methods it needs.

[lbargaoanu]

I don't think it works that way, but feel free to look into it. Zero mobile expertise around here.

[Susko3]

Should be possible to preserve with https://learn.microsoft.com/en-us/xamarin/cross-platform/deploy-test/linker.
Since this is msbuild, I don't think it's possible to have this in the library, so every project using it needs to add their own linker preserve filter.

Not sure how this relates to regular .NET trimming (eg. when using net6.0-android). Maybe some of the attributes used there also apply to the linker.

[lbargaoanu]

Maybe it's easier to use that overload in your own code. It avoids boxing. That's why we switched to it.

[pwelter34]

I struggled with this in blazor for .net 7.0. The following is how i fixed it ...

Project.csproj

<ItemGroup>
  <EmbeddedResource Include="./../ILLink.Descriptors.xml">
    <LogicalName>ILLink.Descriptors.xml</LogicalName>
  </EmbeddedResource>
</ItemGroup>

ILLink.Descriptors.xml

<linker>
  <assembly fullname="AutoMapper" preserve="all" />
  <assembly fullname="System.Runtime">
    <type fullname="System.Enum" preserve="all" />
  </assembly>
</linker>