Review of Nullness Checker

[wmdietl]

No description provided.

[Copilot]

Pull request overview

This PR refines implementation details of the Nullness Checker (NoInit variant), primarily by reducing repeated work in type/annotation scanning and simplifying some receiver-handling logic during method invocability checks.

Changes:

• Simplifies receiver processing in NullnessNoInitVisitor.checkMethodInvocability.
• Reuses a stateful AnnotatedTypeScanner in NullnessNoInitTransfer to reduce allocations.
• Optimizes nullness-annotation detection in NullnessNoInitAnnotatedTypeFactory by canonicalizing aliases once.
• Minor refactor to reduce repeated getTypeArguments() calls in CollectionToArrayHeuristics.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
checker/src/main/java/org/checkerframework/checker/nullness/NullnessNoInitVisitor.java	Simplifies receiver annotation extraction during method invocability checks.
checker/src/main/java/org/checkerframework/checker/nullness/NullnessNoInitTransfer.java	Introduces reusable scanner instance and resets it per visit to avoid repeated allocations.
checker/src/main/java/org/checkerframework/checker/nullness/NullnessNoInitAnnotatedTypeFactory.java	Canonicalizes annotation aliases once before checking canonical nullness qualifier names.
checker/src/main/java/org/checkerframework/checker/nullness/CollectionToArrayHeuristics.java	Small readability refactor by caching type arguments list locally.

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[wmdietl]

@copilot apply changes based on this feedback

[Copilot]

Implemented in 5559ab0. I moved isTopLevel reset into ContainsPolyNullNotAtTopLevelScanner.reset() (calling super.reset()), and removed the explicit polyNullScanner.reset()/state reset in containsPolyNullNotAtTopLevel, so visit(...) performs a single reset per call.

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