test: add unit tests for 16 untested Common extension methods

[rjmurillo]

Summary

• Add 53 new unit tests covering 16 previously untested methods across 8 Common extension classes
• New test files for IMethodSymbolExtensions, ITypeSymbolExtensions, MoqKnownSymbolExtensions, SyntaxNodeExtensions, InvocationExpressionSyntaxExtensions
• Expanded existing tests for ISymbolExtensions, MoqVerificationHelpers, SemanticModelExtensions
• All tests use Roslyn compilation for accurate semantic analysis

Test plan

• CI pedantic build passes (0 warnings, 0 errors)
• All 2328 tests pass locally (60 new tests)
• CI pipeline passes all checks

Closes #897

🤖 Generated with Claude Code

Summary by CodeRabbit

• Tests
  • Expanded unit test coverage across symbol, type, invocation, syntax and verification helpers, adding numerous new scenarios for overloads, parameter/type matching, raises/verify behaviors and Moq-specific detection.
• Chores
  • Centralized and simplified test compilation/setup helpers to streamline in-memory compilations, LINQ and Moq-enabled test flows.

[coderabbitai]

📝 Walkthrough

Walkthrough

Adds a centralized test compilation helper and a large set of unit tests for Common extension methods (IMethodSymbol, ISymbol, ITypeSymbol, invocation/syntax/semantic helpers, Moq-known symbols, and verification helpers). Many existing tests were refactored to use the new CompilationHelper and Moq-aware compilation helpers.

Changes

Cohort / File(s)	Summary
Compilation helper tests/Moq.Analyzers.Test/Helpers/CompilationHelper.cs	New internal helper centralizing metadata references and providing CreateCompilation, CreateMoqCompilationAsync and GetMoqReferencesAsync for tests. Targets: unify Roslyn/Moq compilation setup.
IMethodSymbol tests tests/Moq.Analyzers.Test/Common/IMethodSymbolExtensionsTests.cs	New test class (12 tests) covering Overloads, TryGetOverloadWithParameterOfType, TryGetParameterOfType including null, comparer, cancellation and convenience-overload cases.
ISymbol tests (updates + additions) tests/Moq.Analyzers.Test/Common/ISymbolExtensionsTests.cs	Refactors to use CompilationHelper; adds tests for IsMoqReturnValueSpecificationMethod (Throws/ReturnsAsync/ThrowsAsync) and IsMoqVerificationMethod (VerifySet).
ITypeSymbol tests tests/Moq.Analyzers.Test/Common/ITypeSymbolExtensionsTests.cs	New test class (3 tests) for GetBaseTypesAndThis covering class/object, inheritance chains, and interface-only scenarios.
InvocationExpression syntax tests tests/Moq.Analyzers.Test/Common/InvocationExpressionSyntaxExtensionsTests.cs	New test class (≈10 tests) for finding mocked method/member expressions from Setup lambdas and IsRaisesMethodCall edge cases (nulls, non-lambdas, property access).
MoqKnownSymbols tests tests/Moq.Analyzers.Test/Common/MoqKnownSymbolExtensionsTests.cs	New tests validating MoqKnownSymbols.IsMockReferenced with and without Moq references; includes helpers to build Moq and non-Moq symbol sets.
Moq verification helpers tests (refactor + additions) tests/Moq.Analyzers.Test/Common/MoqVerificationHelpersTests.cs	Refactored to use CompilationHelper/async Moq compilation helpers; adds tests for VerifySet lambda property extraction and TryGetMockedMember symbol/syntax scenarios.
SemanticModel tests (refactor + additions) tests/Moq.Analyzers.Test/Common/SemanticModelExtensionsTests.cs	Refactored to use CompilationHelper; adds/extends tests for FindSetupMethodFromCallbackInvocation, mocked method symbol retrieval, callback/return/raises detection, lambda/event extraction.
SyntaxNode tests tests/Moq.Analyzers.Test/Common/SyntaxNodeExtensionsTests.cs	New test class (7 tests) for FindLocation and GetParentSkippingParentheses across various nesting/edge cases.
Diagnostic & Event & IOperation test updates tests/Moq.Analyzers.Test/Common/DiagnosticExtensionsTests.cs, tests/Moq.Analyzers.Test/Common/EventSyntaxExtensionsTests.cs, tests/Moq.Analyzers.Test/Common/IOperationExtensionsTests.cs, tests/Moq.Analyzers.Test/Common/MoqKnownSymbolsTests.cs	Multiple test files refactored to remove inline CoreReferences and use CompilationHelper/CoreReferencesWithLinq or CoreReferencesWithTasks; removed local static reference setup and replaced CreateCompilation usages with helper calls. Attention: metadata reference changes and async Moq reference resolution.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Possibly related PRs

• test: expand unit test coverage for Common extensions and analyzers #894 — Related large set of tests and test patterns that this change reuses and extends.
• fix: Moq1203 false positives for ReturnsAsync and Callback chaining #886 — Changes to ISymbol/MoqKnownSymbols behavior that the new tests exercise.
• fix: Moq1203 false positive when Setup call is wrapped in parentheses #895 — Adds/changes GetParentSkippingParentheses behavior that is covered by new SyntaxNodeExtensionsTests.

Suggested labels

releasable, feature

Suggested reviewers

• MattKotsenas

🚥 Pre-merge checks | ✅ 5 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 5.33% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately and concisely summarizes the main objective: adding unit tests for 16 untested Common extension methods.
Linked Issues check	✅ Passed	The PR comprehensively addresses all 16 untested methods listed in issue #897 with new unit tests covering the previously untested branches and edge cases.
Out of Scope Changes check	✅ Passed	All changes are directly related to adding unit test coverage for the 16 untested Common extension methods, plus a refactor of shared test compilation boilerplate into CompilationHelper.
Merge Conflict Detection	✅ Passed	✅ No merge conflicts detected when merging into main

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch test/897-untested-common-methods

---

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[gemini-code-assist]

Summary of Changes

Hello @rjmurillo, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly enhances the test suite for the Moq.Analyzers.Common extension methods. By introducing a substantial number of new unit tests and expanding existing ones, it aims to ensure the reliability and correctness of these foundational utility methods, which are critical for the overall functionality of the Moq analyzers. The focus is on comprehensive coverage to prevent regressions and validate expected behavior under various scenarios.

Highlights

• New Unit Tests: Added 53 new unit tests to cover 16 previously untested methods across 8 Common extension classes.
• Expanded Test Coverage: Created new test files for IMethodSymbolExtensions, ITypeSymbolExtensions, MoqKnownSymbolExtensions, SyntaxNodeExtensions, and InvocationExpressionSyntaxExtensions.
• Existing Test Enhancements: Expanded existing test files for ISymbolExtensions, MoqVerificationHelpers, and SemanticModelExtensions to improve coverage.
• Roslyn Compilation: All new and expanded tests utilize Roslyn compilation for accurate semantic analysis, ensuring robust testing.

Changelog

• tests/Moq.Analyzers.Test/Common/IMethodSymbolExtensionsTests.cs
  • Added new unit tests for IMethodSymbolExtensions covering method overloads and parameter type retrieval.
• tests/Moq.Analyzers.Test/Common/ISymbolExtensionsTests.cs
  • Expanded unit tests for ISymbolExtensions to include IsMoqReturnValueSpecificationMethod for Throws, ReturnsAsync, ThrowsAsync and IsMoqVerificationMethod for VerifySet.
• tests/Moq.Analyzers.Test/Common/ITypeSymbolExtensionsTests.cs
  • Added new unit tests for ITypeSymbolExtensions covering base type retrieval for classes and interfaces.
• tests/Moq.Analyzers.Test/Common/InvocationExpressionSyntaxExtensionsTests.cs
  • Added new unit tests for InvocationExpressionSyntaxExtensions covering mocked method/member expression finding and IsRaisesMethodCall.
• tests/Moq.Analyzers.Test/Common/MoqKnownSymbolExtensionsTests.cs
  • Added new unit tests for MoqKnownSymbolExtensions to verify IsMockReferenced behavior with and without Moq compilation.
• tests/Moq.Analyzers.Test/Common/MoqVerificationHelpersTests.cs
  • Updated existing tests and added new tests for MoqVerificationHelpers covering lambda extraction, property extraction from VerifySet lambdas, and mocked member symbol/syntax retrieval.
  • Refactored compilation setup to use shared CreateCompilation and CreateMoqCompilationAsync methods.
• tests/Moq.Analyzers.Test/Common/SemanticModelExtensionsTests.cs
  • Updated existing tests and added new tests for SemanticModelExtensions covering finding setup methods from callback invocations, getting mocked method symbols, and identifying callback/return/raises invocations.
  • Refactored compilation setup to use shared CreateMoqCompilationAsync method.
• tests/Moq.Analyzers.Test/Common/SyntaxNodeExtensionsTests.cs
  • Added new unit tests for SyntaxNodeExtensions covering finding locations of symbols and skipping parentheses in parent traversal.

Activity

• The pull request author, rjmurillo, initiated this change to add unit tests for previously untested Common extension methods.
• 53 new unit tests were added, targeting 16 methods across 8 Common extension classes.
• New test files were introduced for IMethodSymbolExtensions, ITypeSymbolExtensions, MoqKnownSymbolExtensions, SyntaxNodeExtensions, and InvocationExpressionSyntaxExtensions.
• Existing test files for ISymbolExtensions, MoqVerificationHelpers, and SemanticModelExtensions were expanded with additional test cases.
• All tests leverage Roslyn compilation for accurate semantic analysis.
• The author confirmed that the CI pedantic build passes with no warnings or errors.
• Locally, all 2328 tests passed, including the 60 new tests introduced.
• This pull request addresses and closes issue Add unit tests for 16 untested Common extension methods #897.
• The changes were generated with the assistance of Claude Code.

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[deepsource-io]

DeepSource Code Review

DeepSource reviewed changes in the commit range cdc195c..4d44b6a on this pull request. Below is the summary for the review, and you can see the individual issues we found as review comments.

For detailed review results, please see the PR on DeepSource ↗

PR Report Card

Security	× 0 issues		Overall PR Quality    Focus Area: Hygiene Guidance Prioritize fixing 5 methods with `Task` return type not following naming conventions in the tests directory.
Reliability	× 0 issues
Complexity	× 0 issues
Hygiene	× 42 issues

Code Review Summary

Analyzer	Status	Summary	Details
C#		42 new issues detected.	Review ↗

How are these analyzer statuses calculated?

Administrators can configure which issue categories are reported and cause analysis to be marked as failed when detected. This helps prevent bad and insecure code from being introduced in the codebase. If you're an administrator, you can modify this in the repository's settings.

[gemini-code-assist]

Code Review

This pull request significantly improves test coverage by adding 53 new unit tests for 16 previously untested extension methods. The new tests are well-structured, cover a variety of scenarios including edge cases, and use Roslyn's semantic analysis capabilities effectively. The refactoring in existing test files to use common helpers is also a good improvement.

My main feedback is regarding code duplication. Several test files now contain identical helper methods for creating Moq-enabled Roslyn compilations. Consolidating this logic into a shared base class would improve the maintainability of the test suite. Overall, this is a great contribution to the project's quality and robustness.

[codacy-production]

Coverage summary from Codacy

See diff coverage on Codacy

Coverage variation	Diff coverage
✅ +0.00% (target: -1.00%)	✅ ∅ (target: 95.00%)

Coverage variation details

	Coverable lines	Covered lines	Coverage
Common ancestor commit (cdc195c)	2049	1825	89.07%
Head commit (4d44b6a)	2049 (+0)	1825 (+0)	89.07% (+0.00%)

Coverage variation is the difference between the coverage for the head and common ancestor commits of the pull request branch: <coverage of head commit> - <coverage of common ancestor commit>

Diff coverage details

	Coverable lines	Covered lines	Diff coverage
Pull request (#898)	0	0	∅ (not applicable)

Diff coverage is the percentage of lines that are covered by tests out of the coverable lines that the pull request added or modified: <covered lines added or modified>/<coverable lines added or modified> * 100%

See your quality gate settings    Change summary preferences

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@tests/Moq.Analyzers.Test/Common/SemanticModelExtensionsTests.cs`:
- Around line 516-542: The test
FindSetupMethodFromCallbackInvocation_ReturnsChain_FindsSetup duplicates
FindSetupMethodFromCallbackInvocation_ValidReturnsChain_FindsSetupInvocation;
remove the redundant test method entirely (the whole method declaration
including its body) so only one of the two tests invoking
model.FindSetupMethodFromCallbackInvocation with the Returns invocation remains;
verify you keep the intended test (e.g.,
FindSetupMethodFromCallbackInvocation_ValidReturnsChain_FindsSetupInvocation)
and run tests to ensure coverage is unchanged.

[coderabbitai]

Actionable comments posted: 2

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In
`@tests/Moq.Analyzers.Test/Common/InvocationExpressionSyntaxExtensionsTests.cs`:
- Around line 8-20: The test snippets (e.g., in
FindMockedMethodInvocationFromSetupMethod_ValidLambdaWithMethodInvocation_ReturnsInvocation)
use bare expressions like "mock.Setup(x => x.Method())" which are not
compilable; update each const string snippet to be a minimal, compilable script
by declaring a stub Mock type and a mock variable and any minimal Setup
overloads used by the tests (e.g., add a simple class/record/interface and a
Mock class with a Setup method that accepts the same delegate/signature the test
uses), so replace the raw snippet with a small script that declares the stub
types and "var mock = new Mock();" before calling mock.Setup(...); apply the
same wrapping to the other affected test snippets referenced in the comment.

In `@tests/Moq.Analyzers.Test/Helpers/CompilationHelper.cs`:
- Around line 29-40: CoreReferences and CoreReferencesWithLinq currently
allocate new arrays on every access; change them to cached static readonly
fields initialized once (in a static constructor if needed) to avoid repeated
allocations. Replace the expression-bodied properties CoreReferences and
CoreReferencesWithLinq with public/internal properties that return prebuilt
static readonly arrays (e.g., CoreReferencesCache, CoreReferencesWithLinqCache)
populated from CorlibReference, SystemRuntimeReference, SystemLinqReference, and
SystemLinqExpressionsReference during type initialization.