Custom Test Logger registration fails silently if the custom logger doesn't have the ExtensionURI attribute

[bakester14]

Description

After implementing a custom VSTest logger according to the docs here, trying to register it via Friendly or Assembly-qualified name to VSTest.console.exe fails with a misleading error message.

Steps to reproduce

In a new solution, implement a basic test logger following the instructions in the doc linked above. (No need to implement any event handling, just need an Initialize method to compile.) Name it CustomLogger, give it a FriendlyName attribute like this: [FriendlyName("CustomLogger")], and add <AssemblyName>CustomLogger.testlogger</AssemblyName> to the right place in the .csproj file. Then run the following command: vstest.console.exe <path to any test binary> --testadapterpath:<path to directory where your custom logger binary is> --logger:CustomLogger

Expected behavior

VSTest should run, register the logger correctly, and send events to that logger (if implemented). If I spelled something wrong or got it wrong, it should give a clear error instead about the nature of the problem (in this case, that I didn't implement ExtensionUri).

Actual behavior

VSTest fails with the following error: Could not find a test logger with AssemblyQualifiedName, URI or FriendlyName 'CustomLogger'.

Diagnostic logs

N/A (I think)

Environment

Version 16.5.0-dev of vstest.console, Windows 10

[bakester14]

I built and debugged vstest.console for myself and found the following:

At this line, I can see my custom logger has been identified. If you follow the example above, allExtensionPaths should be a List of count 1 with a path to your DLL. So, this isn't a problem with finding the custom loggers.

Diving deeper, I can see that my assembly is loaded just fine.

The problem occurs here, where we check plugin info on the types from the assembly we found. In my case, pluginInfo.IdentifierData is not a null string, but an empty one, which causes a check upstream to fail and filter out the extension.

[hvinett]

@bakester14 ,We added the error message in logs .You can find the changes here