Some MethodInfo(s) of array types loaded by MetadataLoadContext are incorrectly evaluated as equal.

[shin1m]

Description

Some MethodInfo(s) of array types loaded by MetadataLoadContext are incorrectly evaluated as equal.
They are expected not to be equal.

        [Fact]
        public void MethodsShouldBeDistinguished()
        {
            using var context = new MetadataLoadContext(new PathAssemblyResolver(Directory.EnumerateFiles(RuntimeEnvironment.GetRuntimeDirectory(), "*.dll").Append(typeof(ArrayTests).Assembly.Location)));
            Type project(Type x) => context.LoadFromAssemblyName(x.Assembly.FullName).GetType(x.FullName, true);
17          void test(Type type) => Assert.NotEqual(type.GetMethod("Get"), type.GetMethod("Set"));
            test(typeof(int[]));
19          test(project(typeof(int[])));
        }

  Failed MLCTests.ArrayTests.MethodsShouldBeDistinguished [54 ms]
  Error Message:
   Assert.NotEqual() Failure
Expected: Not System.Int32 Get(System.Int32)
Actual:   System.Void Set(System.Int32, System.Int32)
  Stack Trace:
     at MLCTests.ArrayTests.<MethodsShouldBeDistinguished>g__test|0_1(Type type) in .../MLCTests/ArrayTests.cs:line 17
   at MLCTests.ArrayTests.MethodsShouldBeDistinguished() in .../MLCTests/ArrayTests.cs:line 19

MLCTests.tar.gz

Configuration

• System.Reflection.MetadataLoadContext 5.0.1

$ LANG=C dotnet --info
.NET SDK (reflecting any global.json):
 Version:   6.0.100-preview.5.21302.13
 Commit:    d6380bcae7

Runtime Environment:
 OS Name:     arch
 OS Version:  
 OS Platform: Linux
 RID:         arch-x64
 Base Path:   .../sdk/6.0.100-preview.5.21302.13/

Host (useful for support):
  Version: 6.0.0-preview.5.21301.5
  Commit:  ec3e0b276b

Other information

runtime/src/libraries/System.Reflection.MetadataLoadContext/src/System/Reflection/TypeLoading/Types/RoArrayType.cs

Line 150 in 57bfe47

internal sealed override IEnumerable<MethodInfo> GetMethodsCore(NameFilter? filter, Type reflectedType)

In the above method, Get, Set, and Address can have same uniquifier between calls.
I think uniquifier should be consistent for a MetadataLoadContext instance.

[joperezr]

Thanks for the report @shin1m. Do you know if this is a regression from 5.0? cc @steveharter

[shin1m]

@joperezr cc @steveharter

Thanks for the report @shin1m. Do you know if this is a regression from 5.0? cc @steveharter

Sorry, I don't know if or not because 5.0.1 is the first version to me.
According to this view, the code comes from dotnet/corefx#33201 written 3 years ago.

Regards,

[buyaa-n]

Error Message:
Assert.NotEqual() Failure
Expected: Not System.Int32 Get(System.Int32)
Actual: System.Void Set(System.Int32, System.Int32)

@shin1m it doesn't look like they are evaluated as equal, looks it is caused by the Assert.NotEqual()'s logic, I believe if you use Assert.Equal() instead I would fail too

[shin1m]

@buyaa-n the error message of Assert.NotEqual() is confusing.
The test case says that Get and Set should NOT be EQUAL, but it fails.

The other assertions fail as well:

var get = type.GetMethod("Get");
var set = type.GetMethod("Set");
// get and set should not be equal.
// all assertions below fail for array types loaded by MetadataLoadContext.
Asssert.False(get.Equals(set));
Asssert.True(get != set);
Asssert.False(get == set);