fix(dotnet): TRX injection for Microsoft.Testing.Platform projects

[danielmarbach]

Summary

Closes #572. rtk dotnet test was injecting --logger trx --results-directory (VSTest flags) into projects using Microsoft.Testing.Platform (MTP), causing test runs to fail or produce no output. A previous attempt to fix this (PR #745) removed all TRX injection for MTP projects, which was overly conservative — modern MTP frameworks (TUnit 1.19.74+, MSTest, xUnit with MTP runner) include Microsoft.Testing.Extensions.TrxReport natively, so --report-trx works fine.

Detect the test runner mode from project files and global.json, then inject the appropriate TRX flag per mode:

Mode	Detection	Injected flags
Classic (VSTest)	No MTP properties in csproj	--logger trx --results-directory
MtpVsTestBridge	UseMicrosoftTestingPlatformRunner, UseTestingPlatformRunner, or TestingPlatformDotnetTestSupport in project file	-- --report-trx (after -- separator, reaches MTP runtime)
MtpNative	"test": {"runner": "Microsoft.Testing.Platform"} in global.json	--report-trx (direct flag, .NET 10 native mode)

Detection priority: global.json (MtpNative) > project-file properties (MtpVsTestBridge) > Classic. --nologo is skipped for MtpNative since args go directly to the MTP runtime, not MSBuild.

Notes

• VsTestBridge on .NET 10: microsoft.testing.platform.msbuild 2.x blocks the legacy VSTest path on .NET 10 SDK. Users on .NET 10 should use global.json MTP native mode. VsTestBridge remains supported for .NET 9 SDK and earlier.
• TRX file location: In MtpNative mode, TRX files land in bin/Debug//TestResults/ instead of ./TestResults. The existing ./TestResults fallback scanner still picks up user-placed TRX files.
• No framework-specific detection: --report-trx is injected for all MTP projects without checking for specific packages — modern MTP frameworks ship TrxReport natively.

Test plan

• cargo fmt --all && cargo clippy --all-targets && cargo test

• Manual testing: rtk <command> output inspected

  • Unit tests for all three mode detection paths (77 dotnet tests, 1051 total)
  • scan_mtp_kind_in_file covers all three MTP properties
  • inject_report_trx_into_args inserts after existing -- separator or appends -- --report-trx
  • Double-injection guard (has_report_trx_arg)
  • global.json walk-up detection
  • Directory.Build.props walk-up detection
  • Dogfooded with TUnit 1.19.74 on .NET 10: MtpNative mode passes, TRX file created at bin/Debug/net10.0/TestResults/*.trx, exit code propagated correctly

Important: All PRs must target the develop branch (not master).
See CONTRIBUTING.md for details.

[aeppling]

Useless ending 'if' in detect_test_runner_mode

In your function detect_test_runner_mode()
You check at the beginning
if is_global_json_mtp_mode() {
return TestRunnerMode::MtpNative;
}

Then at the end again same, which is never reached

Should be ready to merge

Thanks for this clean contribution, safe fallback on mixed projects, and clean code.

Thanks for you contribution !

On merge

close: #572

[danielmarbach]

@aeppling are you addressing it (PR has push rights) or do you want me to?

[aeppling]

could you trigger ci tests on your side please ? then we will merge once passed
you can push empty commit to trigger

i do not see historical run of those, should run benchmark, clippy, and so on

[CLAassistant]

All committers have signed the CLA.

[danielmarbach]

Cla signed

[danielmarbach]

Useless ending 'if' in detect_test_runner_mode

In your function detect_test_runner_mode() You check at the beginning if is_global_json_mtp_mode() { return TestRunnerMode::MtpNative; }

Then at the end again same, which is never reached

Should be ready to merge

Thanks for this clean contribution, safe fallback on mixed projects, and clean code.

Thanks for you contribution !

On merge

close: #572

Addressed

[aeppling]

Thanks for the contribution !