Fix cross-module ref-type iterator bug and add return/for-of type checks#727
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Fix cross-module ref-type iterator bug and add return/for-of type checks#727
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The monomorphizer incorrectly selected Array<T>^IntoIterator::into_iter instead of &^IntoIterator::into_iter when iterating &Array<T> inside generic functions. This caused Wasm GC type mismatches when ArrayIter and ArrayRefIter had different type indices across module boundaries. Root cause: resolve_method_call_substitution in func_inst.rs overwrote the LocalMethodName's base_struct_name from "&" to "Array" by unwrapping the receiver's reference type. This lost the ref-type impl identity, causing the wrong generic template to be instantiated. Three fixes: 1. Propagate is_ref_impl from MethodInfo to LocalMethodName in resolver 2. Preserve base_struct_name for ref-type impls in monomorphizer 3. Fix Array::iter() to construct ArrayIter directly instead of calling self.into_iter() which returns ArrayRefIter (type mismatch) https://claude.ai/code/session_01Psntc941Uh8sx4iWuvy8Fa
The cross_module_type_identity test is no longer TODO-marked — the loader fix for duplicate ModuleSource identities is already in place. https://claude.ai/code/session_01Psntc941Uh8sx4iWuvy8Fa
on-task-done regenerated WIR golden files reflecting the correct iterator template selection for ref-type impls. https://claude.ai/code/session_01Psntc941Uh8sx4iWuvy8Fa
Same pattern as the Array::iter() fix — calling self.into_iter() on &self dispatches to the wrong IntoIterator impl after the ref-type monomorphization fix. https://claude.ai/code/session_01Psntc941Uh8sx4iWuvy8Fa
- Emit "does not implement IntoIterator" when for-of iterable lacks the trait - Emit "does not implement Iterator" when the iterator type lacks next() - Add e2e test fixtures for both error cases - Fix TreeSet::iter() to construct TreeSetIter directly (same pattern as the Array::iter() fix) https://claude.ai/code/session_01Psntc941Uh8sx4iWuvy8Fa
Working tree is dirtyIntegrity checks produced the following changes: Please run |
Previously `fn foo() -> i32 { return "hello"; }` compiled without error,
producing invalid Wasm. Now the resolver checks that the return value's
type matches the declared return type and emits a compile error on
mismatch.
https://claude.ai/code/session_01Psntc941Uh8sx4iWuvy8Fa
Remove base_type_name fallback — cross-module types must have the same TypeId. Add test for same-name structs from different modules correctly producing a type mismatch error. Also fix a real bug found by this check: u8::try_from(u16) was returning Result::<u16, ConvertError> instead of Result::<u8, ...>. Skip unresolved generics (TypeParam, TypePack, AssocTypeProjection, GenericInstance with params) and function types from the check, as these are resolved after monomorphization. https://claude.ai/code/session_01Psntc941Uh8sx4iWuvy8Fa
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Summary
Array^IntoIterator::into_iter(returnsArrayIter) instead of&^IntoIterator::into_iter(returnsArrayRefIter) when iterating&Array<T>inside generic functions. Root cause:resolve_method_call_substitutionoverwrotebase_struct_namefrom"&"to"Array"by unwrapping the receiver's reference, and the resolver didn't propagateis_ref_impltoLocalMethodName.Array::iter()andTreeSet::iter(): Both calledself.into_iter()which dispatched to the&Timpl returning the wrong iterator type. Now construct iterators directly.fn foo() -> i32 { return "hello"; }previously compiled silently — now emits a compile error. Uses strict TypeId comparison (no base_type_name fallback). Found and fixed a real stdlib bug:u8::try_from(u16)was returningResult::<u16, ConvertError>.Test plan
on-task-donepasses (format, clippy, golden fixtures, test-wado)#![TODO]fixtures now pass:cross_module_variant_iter,test_world_variant_generic,test_world_variant_generic_run,single_module_variant_itererror_return_type_mismatch,error_return_cross_module_same_name,error_for_of_no_into_iterator,error_for_of_no_iteratorhttps://claude.ai/code/session_01Psntc941Uh8sx4iWuvy8Fa