.Net: Add RetainArgumentTypes support to FunctionCallContentBuilder

[ioshm]

Motivation and Context

Before this patch, the FunctionCallContentBuilder did not support retaining the argument types. We need this to support retained argument types when not using auto invoke function choices, i.e: a custom agent loop.

Figured this was small enough to not warrant an issue.

Description

Modified the experimental constructor to include a bool retainArgumentTypes parameter. I decided to update the existing experimental constructor to avoid polluting the class with extra constructors. Not sure if this is considered breaking.

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the SK Contribution Guidelines and the pre-submission formatting script raises no violations
• All unit tests pass, and I have added new tests where possible
• I didn't break anyone (hopefully) 😄

[ioshm]

@microsoft-github-policy-service agree

[ioshm]

The FunctionUsageMetricsAreCapturedByTelemetryAsExpected test seems flaky and races with other tests.

Can reproduce by spamming the following until it races:

dotnet test dotnet\src\Connectors\Connectors.AzureOpenAI.UnitTests --filter "(FullyQualifiedName=SemanticKernel.Connectors.AzureOpenAI.UnitTests.KernelCore.KernelTests.FunctionUsageMetricsAreCapturedByTelemetryAsExpected) | (FullyQualifiedName=SemanticKernel.Connectors.AzureOpenAI.UnitTests.Services.AzureOpenAIChatCompletionServiceTests.GetChatMessageContentsUsesPromptAndSettingsCorrectlyAsync)" --no-build

[xUnit.net 00:00:00.00] xUnit.net VSTest Adapter v3.1.3+b1b99bdeb3 (64-bit .NET 8.0.17)
[xUnit.net 00:00:00.09]   Discovering: SemanticKernel.Connectors.AzureOpenAI.UnitTests
[xUnit.net 00:00:00.21]   Discovered:  SemanticKernel.Connectors.AzureOpenAI.UnitTests
[xUnit.net 00:00:00.23]   Starting:    SemanticKernel.Connectors.AzureOpenAI.UnitTests
[xUnit.net 00:00:00.46]     SemanticKernel.Connectors.AzureOpenAI.UnitTests.KernelCore.KernelTests.FunctionUsageMetricsAreCapturedByTelemetryAsExpected [FAIL]
[xUnit.net 00:00:00.46]       Assert.Contains() Failure: Item not found in collection
[xUnit.net 00:00:00.46]       Collection: [55]
[xUnit.net 00:00:00.46]       Not found:  12
[xUnit.net 00:00:00.46]       Stack Trace:
[xUnit.net 00:00:00.46]         C:\Dayforce\repos\semantic-kernel\dotnet\src\Connectors\Connectors.AzureOpenAI.UnitTests\KernelCore\KernelTests.cs(97,0): at SemanticKernel.Connectors.AzureOpenAI.UnitTests.KernelCore.KernelTests.<>c__DisplayClass6_0.<FunctionUsageMetricsAreCapturedByTelemetryAsExpected>b__2(Instrument instrument, Object state)
[xUnit.net 00:00:00.46]            at System.Diagnostics.Metrics.MeterListener.Dispose()
[xUnit.net 00:00:00.46]         C:\Dayforce\repos\semantic-kernel\dotnet\src\Connectors\Connectors.AzureOpenAI.UnitTests\KernelCore\KernelTests.cs(117,0): at SemanticKernel.Connectors.AzureOpenAI.UnitTests.KernelCore.KernelTests.FunctionUsageMetricsAreCapturedByTelemetryAsExpected()
[xUnit.net 00:00:00.46]         --- End of stack trace from previous location ---
[xUnit.net 00:00:00.46]   Finished:    SemanticKernel.Connectors.AzureOpenAI.UnitTests
  Connectors.AzureOpenAI.UnitTests test failed with 1 error(s) (1.5s)
    C:\Dayforce\repos\semantic-kernel\dotnet\src\Connectors\Connectors.AzureOpenAI.UnitTests\KernelCore\KernelTests.cs(97): error TESTERROR:
      SemanticKernel.Connectors.AzureOpenAI.UnitTests.KernelCore.KernelTests.FunctionUsageMetricsAreCapturedByTelemetryAsExpected (189ms): Error Message: Assert.Contains() Failure: Item not found in collection
      Collection: [55]
      Not found:  12
      Stack Trace:
         at SemanticKernel.Connectors.AzureOpenAI.UnitTests.KernelCore.KernelTests.<>c__DisplayClass6_0.<FunctionUsageMetricsAreCapturedByTelemetryAsExpected>b__2(Instrument instrument, Object state) in C:\Day
      force\repos\semantic-kernel\dotnet\src\Connectors\Connectors.AzureOpenAI.UnitTests\KernelCore\KernelTests.cs:line 97
         at System.Diagnostics.Metrics.MeterListener.Dispose()
         at SemanticKernel.Connectors.AzureOpenAI.UnitTests.KernelCore.KernelTests.FunctionUsageMetricsAreCapturedByTelemetryAsExpected() in C:\Dayforce\repos\semantic-kernel\dotnet\src\Connectors\Connectors.A
      zureOpenAI.UnitTests\KernelCore\KernelTests.cs:line 117
      --- End of stack trace from previous location ---

Test summary: total: 2, failed: 1, succeeded: 1, skipped: 0, duration: 1.4s
Build failed with 1 error(s) in 1.9s

Can also reproduce from VS by running these two tests in parallel until failure.

[ioshm]

Find a fix in e08e4d1.

This bit of code can be triggered concurrently (from two parallel tests). The Add call on the List<long> is not thread-safe, giving raise to a lost update problem when there is more than 1 concurrent writer.

semantic-kernel/dotnet/src/Connectors/Connectors.AzureOpenAI.UnitTests/KernelCore/KernelTests.cs

Lines 83 to 90 in e08e4d1

	listener.SetMeasurementEventCallback<long>((instrument, measurement, tags, state) =>
	{
	if (instrument.Name == "semantic_kernel.function.invocation.token_usage.prompt" ||
	instrument.Name == "semantic_kernel.function.invocation.token_usage.completion")
	{
	measurements[instrument.Name].Add(measurement);
	}
	});

Fix the problem by using a thread-safe collection, ConcurrentBag<long>.