fix(ksp): skip parameterized supertypes in TypeExtractor.fallbackType()

[bangbang93]

Problem

TypeExtractor.fallbackType() crashes with IllegalStateException when processing MongoDB @Document classes with ObjectId fields. The function was calling toClassName() on parameterized supertypes like Comparable<ObjectId>, which throws an exception because KotlinPoet's toClassName() doesn't support parameterized types.

Solution

Added a guard to check supertype.arguments.isEmpty() before calling toClassName() in the Comparable check. This skips parameterized supertypes like Comparable<ObjectId> which cannot be converted.

Changes

• File: querydsl-tooling/querydsl-ksp-codegen/src/main/kotlin/com/querydsl/ksp/codegen/TypeExtractor.kt
• Change: Added supertype.arguments.isEmpty() && guard in fallbackType() method

Testing

• All 10 existing tests in querydsl-ksp-codegen pass
• Minimal one-line change, no API changes or breaking changes
• Backward compatible

Fixes #1688

[Copilot]

Pull request overview

Fixes a KSP crash in TypeExtractor.fallbackType() when encountering parameterized supertypes (e.g., Comparable<ObjectId>) that cannot be converted via KotlinPoet’s toClassName().

Changes:

• Adds a guard to skip parameterized supertypes before calling toClassName() while checking for Comparable.

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[Copilot]

The new supertype.arguments.isEmpty() guard prevents Comparable<T> (which is almost always parameterized) from ever being recognized as comparable. That avoids the crash, but it also changes behavior: types like ObjectId : Comparable<ObjectId> will now be treated as SimpleType.Simple (SimplePath) instead of SimpleType.Comparable (ComparablePath), likely reducing supported comparison operators.

Instead of skipping parameterized supertypes, compare using the supertype declaration (e.g., supertype.declaration.qualifiedName?.asString() or supertype.declaration.toClassName().canonicalName) so you can safely detect Comparable regardless of type arguments without calling toClassName() on the KSType itself.

Suggested change

	// Skip parameterized types (e.g. Comparable<ObjectId>) — toClassName() throws for them
	supertype.arguments.isEmpty() && comparableNames.contains(supertype.toClassName().canonicalName)
	comparableNames.contains(supertype.declaration.qualifiedName?.asString())

[Copilot]

This change fixes a crash scenario around parameterized supertypes, but there is no regression test covering fallbackType() with a type that implements Comparable<T> (e.g., MongoDB ObjectId). Adding a focused unit/integration test that exercises TypeExtractor.fallbackType() for a parameterized Comparable supertype would prevent reintroducing the toClassName() IllegalStateException and ensure the resulting QPropertyType is correct.

Suggested change

	// Skip parameterized types (e.g. Comparable<ObjectId>) — toClassName() throws for them
	supertype.arguments.isEmpty() && comparableNames.contains(supertype.toClassName().canonicalName)
	val supertypeDeclaration = supertype.declaration as? KSClassDeclaration
	val qualifiedName = supertypeDeclaration?.qualifiedName?.asString()
	comparableNames.contains(qualifiedName)