Local classes and constructors

How tests that construct classes declared in the same file are compared.

What counts as the same

Constructor calls and classes

• A constructor call keeps its callee, its ordered arguments and its generic arguments.
• A local class declaration, class expression or owned alias keeps its implementation and its nominal identity. Two distinct class objects do not become interchangeable merely because their methods look the same.
• Fields, methods, accessors, private names, heritage and static initialization all take part in the comparison. Definition-time effects stay separate from construction.
• References to separate local instances keep their declaration identity even when their classes and construction arguments are identical.
• Consistent local renaming stays comparable.
• Parentheses and erased TypeScript as, satisfies, non-null and angle-bracket assertions on these paths keep the same constructor behavior.

Captured values

A test body can use values declared outside it, and readable .each cells.

• A capture keeps which enclosing variable it uses, even when two variables start with equal values. Consistently renaming those variables stays comparable.
• Proven direct assignments update a captured scalar or constructor alias.
• Captured arrays and objects keep their initializer and their supported straight-line receiver mutations. Mutable captured objects keep one ordered history across proven owned constructions and mutations.
• Literal-only variations can still produce a parameterization-candidate; that finding says to preserve both cases.
• Declared functions and expression or arrow closures share owned lexical capture environments. Ordinary helper renaming stays comparable until its name is observed, and callable aliases keep the original function name.
• Vitest mock captures and plain TypeScript parameter properties are modeled.

Names that stay values

• Known class names, intrinsic constructor names and observed stable callable names.
• Observed private method and callable-field names. Explicit function names survive private storage renaming.
• Ordinary private object data properties named name or toString stay comparable.

What is left out of comparison

State the analyzer cannot model makes the dependent body unresolved, and an unresolved body is excluded from comparison:

• dynamic control-flow writes
• escaping captured objects
• unknown class-object mutations
• dynamic reflective overrides
• source-text reflection
• decorators
• unowned factory results
• replaced or escaping private callables
• callable metadata writes or escapes
• a helper that returns a captured mutable object

Only the consumers are affected: unrelated tests remain comparable, and unresolved hooks and fixtures affect only the tests that use them. Bounded class-summary and history caches degrade visibly when their budgets are exceeded.

Native and imported constructor bindings keep their existing syntactic comparison. Their conditional writes do not enter the owned local-class state model.

Loop initializers and templates

Behavior collection visits for expression and declaration initializers and ordinary template interpolations. It keeps nested calls, constructors and other modeled effects in source order and in deferred scope. Tagged-template call modeling is separate.

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