Align diagnostic environment variable names with command-line options

[Copilot]

Command-line options were renamed in #6165 (--diagnostic-output-fileprefix → --diagnostic-file-prefix, --diagnostic-filelogger-synchronouswrite → --diagnostic-synchronous-write), but environment variable names were not updated, creating inconsistency.

Changes

• Renamed TESTINGPLATFORM_DIAGNOSTIC_OUTPUT_FILEPREFIX → TESTINGPLATFORM_DIAGNOSTIC_FILE_PREFIX
• Renamed TESTINGPLATFORM_DIAGNOSTIC_FILELOGGER_SYNCHRONOUSWRITE → TESTINGPLATFORM_DIAGNOSTIC_SYNCHRONOUS_WRITE
• Updated references in TestApplication.cs and integration tests

Example

// Before (inconsistent)
environment.GetEnvironmentVariable(EnvironmentVariableConstants.TESTINGPLATFORM_DIAGNOSTIC_OUTPUT_FILEPREFIX)

// After (matches --diagnostic-file-prefix)
environment.GetEnvironmentVariable(EnvironmentVariableConstants.TESTINGPLATFORM_DIAGNOSTIC_FILE_PREFIX)

Breaking Change

Users setting TESTINGPLATFORM_DIAGNOSTIC_OUTPUT_FILEPREFIX or TESTINGPLATFORM_DIAGNOSTIC_FILELOGGER_SYNCHRONOUSWRITE must update to the new names.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• kijvsblobprodcus387.vsblob.vsassets.io
  • Triggering command: /usr/bin/dotnet dotnet build ./src/Platform/Microsoft.Testing.Platform/Microsoft.Testing.Platform.csproj (dns block)
• rcxvsblobprodcus328.vsblob.vsassets.io
  • Triggering command: /home/REDACTED/work/testfx/testfx/.dotnet/dotnet /home/REDACTED/work/testfx/testfx/.dotnet/dotnet msbuild /m /nologo /clp:Summary /v:minimal /nr:true /warnaserror /p:TreatWarningsAsErrors=true /p:ContinuousIntegrationBuild=false /home/REDACTED/work/testfx/testfx/artifacts/toolset/restore.proj /t:__WriteToolsetLocation /clp:ErrorsOnly;NoSummary /p:__ToolsetLocationOutputFile=/home/REDACTED/work/testfx/testfx/artifacts/toolset/11.0.0-beta.25617.1.txt (dns block)
  • Triggering command: /usr/bin/dotnet dotnet build ./src/Platform/Microsoft.Testing.Platform/Microsoft.Testing.Platform.csproj (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Inconsistent diagnostic option names for command line and environment variable</issue_title>
<issue_description>## Describe the bug

Diagnostic option name was renamed from --diagnostic-output-fileprefix to --diagnostic-file-prefix (#6165) but the environment variable name is still TESTINGPLATFORM_DIAGNOSTIC_OUTPUT_FILEPREFIX.

https://github.com/dotnet/docs/blob/fde0a56ed2df06307faec6bfa9fba7ea7e687f02/docs/core/testing/microsoft-testing-platform-migration-from-v1-to-v2.md?plain=1#L70

This problem also exists for --diagnostic-synchronous-write option (former --diagnostic-filelogger-synchronouswrite).

The documentation is still using the old option name:
https://github.com/dotnet/docs/blob/main/docs/core/testing/microsoft-testing-platform-extensions-diagnostics.md

Steps To Reproduce

Check code for diagnostic extension and documentation:

testfx/src/Platform/Microsoft.Testing.Platform/CommandLine/PlatformCommandLineProvider.cs

Line 18 in 4e84b84

public const string DiagnosticOutputFilePrefixOptionKey = "diagnostic-file-prefix";

testfx/src/Platform/Microsoft.Testing.Platform/Helpers/EnvironmentVariableConstants.cs

Line 23 in 4e84b84

public const string TESTINGPLATFORM_DIAGNOSTIC_OUTPUT_FILEPREFIX = nameof(TESTINGPLATFORM_DIAGNOSTIC_OUTPUT_FILEPREFIX);

https://github.com/dotnet/docs/blob/fde0a56ed2df06307faec6bfa9fba7ea7e687f02/docs/core/testing/microsoft-testing-platform-extensions-diagnostics.md?plain=1#L21

https://github.com/dotnet/docs/blob/fde0a56ed2df06307faec6bfa9fba7ea7e687f02/docs/core/testing/microsoft-testing-platform-extensions-diagnostics.md?plain=1#L31

Expected behavior

documentation and environment variable name use identical name e.g. environment name: TESTINGPLATFORM_DIAGNOSTIC_FILE_PREFIX

Actual behavior

names are mixed up in documentation and implementation

</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Inconsistent diagnostic option names for command line and environment variable #7159

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[Youssef1313]

It's not going to affect many, but it's a breaking change and I'm not sure if we should take it at this point.