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Data-driven tests are not fully supported for overloaded test methods

See original GitHub issue

Description

The MSTest V2 test framework does not appear to correctly support overloaded data-driven test methods. Only tests for the first overload are actually found and executed.

Steps to reproduce

Compile and execute the unit tests in the following code fragment:

using System.Globalization;

namespace TestProject1
{
    [TestClass]
    public class UnitTest1
    {
        [DataTestMethod]
        [DynamicData(nameof(Equal_StringAndInt32), DynamicDataSourceType.Method)]
        public void Equal(string x, int y)
        {
            Assert.AreEqual(x, y.ToString(CultureInfo.InvariantCulture));
        }

        [DataTestMethod]
        [DynamicData(nameof(Equal_Int32AndString), DynamicDataSourceType.Method)]
        public void Equal(int x, string y)
        {
            Assert.AreEqual(x.ToString(CultureInfo.InvariantCulture), y);
        }

        private static IEnumerable<object[]> Equal_StringAndInt32()
        {
            yield return new object[] {"1", 1};
            yield return new object[] {"2", 1};
        }

        private static IEnumerable<object[]> Equal_Int32AndString()
        {
            yield return new object[] {1, "0"};
            yield return new object[] {2, "2"};
        }
    }
}

Expected behavior

The test results in both Visual Studio and the console runner report 4 tests: two for the Equal(int x, string x) overload and two for the Equal(string x, int x) overload. For each of these overloads, one test should pass, and one should fail.

Actual behavior

Only the results for the Equal(int x, string x) overload are reported in Test Explorer:

Running dotnet test -t --nologo --no-restore --no-build also finds only two tests:

Test run for TestProject1.dll (.NETCoreApp,Version=v6.0)
The following Tests are available:
    Equal (1,1)
    Equal (2,1)

Running dotnet test --nologo --no-restore --no-build only executes two tests:

Test run for TestProject1.dll (.NETCoreApp,Version=v6.0)
Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
  Failed Equal (2,1) [13 ms]
  Error Message:
   Assert.AreEqual failed. Expected:<2>. Actual:<1>.
  Stack Trace:
     at TestProject1.UnitTest1.Equal(String x, Int32 y) in C:\Users\exg906\source\repos\TestProject1\UnitTest1.cs:line 12


Failed!  - Failed:     1, Passed:     1, Skipped:     0, Total:     2, Duration: 32 ms - TestProject1.dll (net6.0)