Fix compilation error in DefaultRepositorySystemReentrancyTest

[gnodet]

Summary

• Commit 89f2bc1 ("Extend re-entrancy detection for broken trace chains") added three new test methods in DefaultRepositorySystemReentrancyTest that construct DefaultRepositorySystemValidator using Collections.singletonList(EXPRESSION_REJECTING_VALIDATOR_FACTORY)
• However, commit f164aa9 ("Allow validator factory to abstain", Enh: Allow validator factory to abstain #2008) changed the constructor from List<ValidatorFactory> to Map<String, ValidatorFactory>
• This causes a compilation failure on all 18 CI jobs (every OS × JDK × Maven combination): incompatible types: no instance(s) of type variable(s) T exist so that java.util.List<T> conforms to java.util.Map<java.lang.String,org.eclipse.aether.spi.validator.ValidatorFactory>

The fix replaces Collections.singletonList(...) with Collections.singletonMap("expressionRejecting", ...) at all three call sites (lines 361, 398, 457), consistent with the existing correct usage at line 174.

Test plan

• mvn -pl maven-resolver-impl test-compile compiles successfully
• mvn -pl maven-resolver-impl test -Dtest=DefaultRepositorySystemReentrancyTest — all 11 tests pass
• CI should go green

🤖 Generated with Claude Code

[gnodet]

LGTM. Straightforward compilation fix — commit 89f2bc1 added test methods using Collections.singletonList() for DefaultRepositorySystemValidator, but commit f164aa9 had already changed the constructor from List<ValidatorFactory> to Map<String, ValidatorFactory>. The fix correctly replaces singletonList with singletonMap at all three call sites, matching the existing usage at line 174.

This review was generated by an AI agent and may contain inaccuracies. Please verify all suggestions before applying.

Claude Code on behalf of gnodet

[gnodet]

The single CI failure is the pre-existing flaky JettyTransporterTest.testGet_HTTP3 on Windows (windows-latest jdk-26-zulu 4.0.0-rc-6):

JettyTransporterTest.testGet_HTTP3 — IllegalState: Failed to find a port free for both TCP and UDP

This is a known infrastructure flake (there's even a recent deflake attempt in 8ea57ef). All other 17 matrix jobs (ubuntu/macos/windows × JDK 21/25/26 × Maven 3.10/4.0) pass cleanly, including the DefaultRepositorySystemReentrancyTest — 11/11 tests pass.

[github-actions]

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