fix(analysis): analyzer validation checks source project success instead of test project success

[Copilot]

The analyzer validation incorrectly rejected projects for mutation when test projects failed analysis, even though the source project succeeded.

Root Cause

findMutableAnalyzerResults is a Dictionary<IAnalyzerResult, List<IAnalyzerResult>> where:

• Key: source/mutable project to be mutated
• Value: test projects that reference it

The validation at line 112 checked if test projects succeeded:

if (findMutableAnalyzerResults.All(p => p.Value.All(r => !r.Succeeded)))

This conflicted with the error message which correctly reported the source projects as failed.

Changes

• InputFileResolver.cs:112: Changed validation to check source project success: !p.Key.Succeeded
• Tests: Added coverage for both scenarios:
  • Source succeeds + test fails → proceeds with mutation
  • Source fails → throws InputException

The fix allows mutation testing when test project analysis fails but source project analysis succeeds, which is the common case for many valid projects.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Analyzer results are invalid if test project analyzer result is not succeeded</issue_title>
<issue_description>Describe the bug

stryker-net/src/Stryker.Core/Stryker.Core/Initialisation/InputFileResolver.cs

Line 112 in aac130a

if (findMutableAnalyzerResults.All(p => p.Value.All(r => !r.Succeeded)) )

considers a project invalid for mutation if it's mapped test projects analyzer results are invalid, I'm not sure why this is the case but while working on #3386 I am observing that this is the case for many projects that otherwise mutation test without issues after changing the condition to check the target project succeeded instead.

@dupdob can you clarify whether this is a bug or if this check is required for another scenario?
</issue_description>

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

• Fixes Analyzer results are invalid if test project analyzer result is not succeeded #3390

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[Copilot]

Pull request overview

This PR fixes a critical logic error in analyzer validation that incorrectly rejected source projects for mutation when test project analysis failed, even though the source projects succeeded. The fix changes the validation to check source project success status instead of test project success status, which aligns with the error message that was already reporting failed source projects.

Key Changes

• Changed the validation condition from checking test project success to checking source project success
• Updated test name to better reflect the new behavior
• Added comprehensive test coverage for both scenarios (test failure with source success, and source failure)

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
InputFileResolver.cs	Fixed validation logic at line 112 to check !p.Key.Succeeded (source project) instead of p.Value.All(r => !r.Succeeded) (test projects)
InputFileResolverTests.cs	Renamed test from ShouldHandleFailedAnalysis to ShouldSucceedWhenTestProjectFailsButSourceProjectSucceeds and added new test ShouldThrowWhenSourceProjectFailsAnalysis for comprehensive coverage