The 0100 identity fix registers a namespaced import's own functions under a
module-qualified name (ns.fn) in fn_ast_map WITHOUT an eager declareFunction,
so the alias is lowered through lazyLowerFunction's null-FuncId lowerFunction
path. That path had no Function.source_file to restore (the non-null path does
setCurrentSourceFile(func.source_file)), so the alias lowered in the CALLER's
visibility context. A qualified function that called a helper from its OWN
module's flat import was then rejected "not visible".
Fix:
- ProgramIndex.qualified_fn_source maps each ns.fn alias to its declaring
source file, populated in registerQualifiedFn (current_source_file is
pinned to the decl's source by registerNamespaceQualifiedFns).
- lazyLowerFunction's null-FuncId branch restores that source before
lowerFunction, so ns.fn's body lowers in its own module's context and its
intra-module / own-import callees resolve.
- lowerFunction records Function.source_file = current_source_file on the
freshly-begun function (matching declareFunction), so the lowered alias
carries its own module for diagnostics/emit.
Regression: examples/0720-modules-qualified-own-import.sx — calc.compute (a
qualified alias) calls triple/base from calc.sx's own flat import; reports
"'triple' is not visible" on the attempt-1 code, passes after. 0719's
cross-module dual-parse assertion stays green. issues/0100 RESOLVED banner
extended with the F1 follow-up.