fix(lua): close latest resolver review findings

gitnexus/src/core/ingestion/export-detection.ts

@@ -242,8 +242,15 @@ export const rubyExportChecker: ExportChecker = (_node, _name) => true;
 
 /** Lua: `function foo()` is global (reachable from other files via require/_G);
  *  `local function foo()` is module-private. */
-export const luaExportChecker: ExportChecker = (node, _name) =>
-  node.type !== 'local_function_definition_statement';
+export const luaExportChecker: ExportChecker = (node, _name) => {
+  let current: SyntaxNode | null = node;
+  while (current !== null) {
+    if (current.type === 'local_function_definition_statement') return false;
+    if (current.type === 'function_definition_statement') return true;
+    current = current.parent;
+  }
+  return true;
+};
 
 /** Dart: public if no leading underscore (convention, same as Python). */
 export const dartExportChecker: ExportChecker = (_node, name) => !name.startsWith('_');

gitnexus/src/core/ingestion/languages/lua/captures.ts

@@ -42,7 +42,7 @@ const LUA_CALLABLE_CAPTURE_OPTIONS = {
     'function_definition',
   ]),
   callNodeTypes: new Set(['call']),
-  parameterListNodeTypes: new Set(['parameter_list', 'argument_list']),
+  parameterListNodeTypes: new Set(['parameters', 'parameter_list', 'argument_list']),
   parameterNodeTypes: new Set(['identifier', 'vararg_expression']),
   bindingNodeTypes: new Set(['local_variable_declaration']),
   assignmentNodeTypes: new Set(['variable_assignment']),
@@ -303,7 +303,11 @@ function addLuaArityCaptures(
   functionNode: Parser.SyntaxNode,
 ): void {
   const parameters = functionNode.childForFieldName('parameters');
-  if (parameters?.type !== 'parameter_list') return;
+  if (
+    parameters === null ||
+    !LUA_CALLABLE_CAPTURE_OPTIONS.parameterListNodeTypes.has(parameters.type)
+  )
+    return;
   const hasVararg = parameters.namedChildren.some((child) => child.type === 'vararg_expression');
   const fixedCount = parameters.namedChildren.filter(
     (child) => child.type !== 'vararg_expression',

gitnexus/src/core/tree-sitter/parser-loader.ts

@@ -44,7 +44,7 @@ interface GrammarSource {
   /**
    * When true, this grammar may be disabled at runtime via
    * `GITNEXUS_SKIP_OPTIONAL_GRAMMARS`. Set ONLY on genuinely-optional grammars
-   * (optionalDependencies / vendored — swift/dart/kotlin/zig). Required dependencies
+   * (optionalDependencies / vendored — swift/dart/kotlin/zig/lua). Required dependencies
    * routed through the optional machinery for ABI safety (e.g. C, which is
    * `optional: true` + `severity: 'error'`) must NOT set this — opting out of a
    * required parser is always an install/platform problem, never a user choice.

gitnexus/test/unit/language-skip.test.ts

@@ -27,14 +27,20 @@ describe('isLanguageAvailable', () => {
     expect(isLanguageAvailable(SupportedLanguages.Swift)).toBe(true);
   });
 
-  it('reports Lua availability according to the optional grammar state', () => {
+  it('reports Lua availability according to the optional grammar state', async () => {
     const available = isLanguageAvailable(SupportedLanguages.Lua);
     if (isGrammarRuntimeSkipped(SupportedLanguages.Lua)) {
       expect(available).toBe(false);
     } else {
-      // Lua is optional and may be unavailable when no matching prebuild or
-      // local native toolchain exists, even without an explicit skip flag.
-      expect(typeof available).toBe('boolean');
+      // Without an explicit skip, availability is install-dependent. Check
+      // that the boolean probe agrees with the actual optional load result.
+      try {
+        await loadLanguage(SupportedLanguages.Lua);
+        expect(available).toBe(true);
+      } catch (error) {
+        expect(error).toBeInstanceOf(Error);
+        expect(available).toBe(false);
+      }
     }
   });
 

gitnexus/test/unit/parser-loader-skip-optional.test.ts

@@ -45,11 +45,13 @@ describe('parser-loader GITNEXUS_SKIP_OPTIONAL_GRAMMARS runtime gate', () => {
   });
 
   it('a comma list can name zig on its own', async () => {
+    const base = await freshLoader(undefined);
+    const luaBase = base.isLanguageAvailable(SupportedLanguages.Lua);
     const { isLanguageAvailable, isGrammarRuntimeSkipped } = await freshLoader('zig');
     expect(isLanguageAvailable(SupportedLanguages.Zig)).toBe(false);
     expect(isGrammarRuntimeSkipped(SupportedLanguages.Zig)).toBe(true);
     expect(isGrammarRuntimeSkipped(SupportedLanguages.Swift)).toBe(false);
-    expect(isLanguageAvailable(SupportedLanguages.Lua)).toBe(false);
+    expect(isLanguageAvailable(SupportedLanguages.Lua)).toBe(luaBase);
   });
 
   it('skip=all/true/* also skip every optional grammar', async () => {

gitnexus/test/unit/scope-resolution/import-target-index-reuse.contract.test.ts

@@ -543,6 +543,10 @@ const FIXTURES: ReadonlyMap<SupportedLanguages, ImportTargetFixture> = new Map<
       parsedImport: IGNORES_CONTEXT,
       // See `minimumScans` on the interface: membership probes only.
       minimumScans: 0,
+      minimumParsedFileReads: 0,
+    },
+  ],
+  [
     SupportedLanguages.Lua,
     {
       files: ['lib/models.lua', 'lib/main.lua'],