feat(resolution): inherited this.X, Java/Kotlin cross-file method refs, Swift type scoping (#810)

Three callback-registration shapes deferred from #756/#808, one arc:

1. INHERITED this.X (TS/JS + every this.-routed language): a `this.<member>`
   registration whose member isn't on the enclosing class defers to a second
   pass (resolveDeferredThisMemberRefs — in-memory like deferredChainRefs,
   runs after implements/extends edges persist, same lifecycle as the #750
   conformance pass) and resolves up the supertype chain, depth-capped BFS,
   validated targets only. `bus.on("submit", this.handleSubmit)` in a
   subclass links to FormBase::handleSubmit; same-named methods on unrelated
   classes never match. this.-prefixed candidates skip the extraction name
   gate (an inherited member can't be in definedHere).

2. JAVA/KOTLIN qualified method refs: `Handlers::onMessage` /
   `OtherClass::handle` emit QUALIFIED names resolved by the scoped
   suffix-matcher — cross-file capable, gated on the scope name being a
   same-file type or an imported name (dotted JVM imports now contribute
   their last segment). `this::m` and `super::m` route through the
   class-scoped resolver (super rides the supertype pass). References
   through a VARIABLE (`subscriber::onNext`) deliberately produce nothing —
   receiver type is unknowable; RxJava's baseline bare capture was resolving
   these to same-named same-file methods (a test method "registering" an
   anonymous class's onNext) — the rework drops 18 such wrong edges and
   keeps the 7 genuine Type::method refs RxJava's main tree actually has.

3. SWIFT enclosing-type scoping (implicit self): bare callback names match
   methods only of the from-symbol's own type (extension/nested scopes
   reconciled by suffix), and top-level code never matches methods.
   Alamofire: −44 wrong edges (parameters like `request`/`data`/`retrier`
   resolving to same-named methods on unrelated protocols), all verified;
   the same-class param collision (`task`) remains and is documented.

New ResolutionContext.getNodeById lets matchers derive the from-symbol's
class scope. Controls: redis/fmt fnref edges byte-identical; excalidraw
stable; typeorm +4 genuine inherited-getter dependencies; zero calls edges
changed on any of 7 A/B repos; nodes identical everywhere. Kotlin
companion-object members extract unqualified (pre-existing) so
`Type::companionFn` stays silent rather than guessing — documented.

Full suite 1389 passed. EXTRACTION_VERSION 20 → 21 (re-index to benefit).

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/extraction/extraction-version.ts

@@ -21,4 +21,4 @@
  * turns the re-index hint into noise — keep it honest (see CLAUDE.md, "Honesty
  * in the product is load-bearing").
  */
-export const EXTRACTION_VERSION = 20;
+export const EXTRACTION_VERSION = 21;

src/extraction/function-ref.ts

@@ -553,35 +553,66 @@ function normalizeSpecial(
   source: string
 ): Array<{ name: string; node: SyntaxNode }> {
   switch (type) {
-    // Java `Main::targetCb` / `this::run0` — last identifier child is the method.
+    // Java method references. Receiver decides the resolution route (#808):
+    //   `this::run0` / `super::close` → `this.<m>` (class-scoped resolver;
+    //     super rides the inherited-member supertype pass)
+    //   `Type::method` (capitalized) → qualified `Type::method` (suffix-
+    //     matched against that type's members, cross-file capable)
+    //   `variable::method` → nothing (receiver type unknown statically —
+    //     the deferred obj.method class)
     case 'method_reference': {
       let last: SyntaxNode | null = null;
       for (let i = 0; i < node.namedChildCount; i++) {
         const child = node.namedChild(i);
         if (child && child.type === 'identifier') last = child;
       }
-      return last ? [{ name: getNodeText(last, source), node: last }] : [];
-    }
-
-    // Kotlin `::targetCb` — the simple_identifier child.
-    case 'callable_reference': {
-      for (let i = 0; i < node.namedChildCount; i++) {
-        const child = node.namedChild(i);
-        if (child && child.type === 'simple_identifier') {
-          return [{ name: getNodeText(child, source), node: child }];
-        }
+      if (!last) return [];
+      const m = getNodeText(last, source);
+      const text = getNodeText(node, source);
+      if (text.startsWith('this::') || text.startsWith('super::')) {
+        return [{ name: `this.${m}`, node: last }];
+      }
+      const recv = text.match(/^([A-Z][A-Za-z0-9_]*)\s*::/);
+      if (recv) {
+        // `Type::method` — but `Type::new` (constructor ref) has no method
+        // node to land on; let the stoplist drop it via the bare name.
+        return m === 'new' ? [] : [{ name: `${recv[1]}::${m}`, node: last }];
       }
       return [];
     }
 
+    // Kotlin `::targetCb` (one part) / `OtherClass::handle` (two parts —
+    // receiver is a type_identifier; lowercase receivers are variables, the
+    // deferred obj.method class).
+    case 'callable_reference': {
+      let receiver: SyntaxNode | null = null;
+      let member: SyntaxNode | null = null;
+      for (let i = 0; i < node.namedChildCount; i++) {
+        const child = node.namedChild(i);
+        if (!child) continue;
+        if (child.type === 'type_identifier') receiver = child;
+        if (child.type === 'simple_identifier') member = child;
+      }
+      if (!member) return [];
+      const m = getNodeText(member, source);
+      if (!receiver) return [{ name: m, node: member }]; // ::topLevelFn
+      const recvText = getNodeText(receiver, source);
+      return /^[A-Z]/.test(recvText)
+        ? [{ name: `${recvText}::${m}`, node: member }]
+        : []; // variable::method — unknown receiver type
+    }
+
     // Kotlin `this::fire` parses as navigation_expression with a `::fire`
-    // navigation_suffix. Ordinary `a.b` navigation MUST yield nothing.
+    // navigation_suffix — route through the class-scoped `this.` resolver.
+    // Ordinary `a.b` navigation (and any non-`this` receiver) MUST yield
+    // nothing.
     case 'navigation_expression': {
+      if (!getNodeText(node, source).startsWith('this::')) return [];
       for (let i = 0; i < node.namedChildCount; i++) {
         const child = node.namedChild(i);
         if (child && child.type === 'navigation_suffix' && getNodeText(child, source).startsWith('::')) {
           const id = child.namedChild(child.namedChildCount - 1);
-          if (id) return [{ name: getNodeText(id, source), node: id }];
+          if (id) return [{ name: `this.${getNodeText(id, source)}`, node: id }];
         }
       }
       return [];

src/extraction/tree-sitter.ts

@@ -435,19 +435,34 @@ export class TreeSitterExtractor {
     if (isGeneratedFile(this.filePath)) return;
 
     const definedHere = new Set<string>();
+    const definedTypes = new Set<string>();
     for (const n of this.nodes) {
       if (n.kind === 'function' || n.kind === 'method') definedHere.add(n.name);
+      if (
+        n.kind === 'class' || n.kind === 'struct' || n.kind === 'interface' ||
+        n.kind === 'enum' || n.kind === 'trait' || n.kind === 'protocol'
+      ) {
+        definedTypes.add(n.name);
+      }
     }
 
     // Import-binding names only (all binding emitters push kind 'imports').
     // Deliberately NOT 'references': those carry type-annotation and
     // interface-member names, which let local variables that share a type
-    // member's name slip through the gate (excalidraw A/B finding).
+    // member's name slip through the gate (excalidraw A/B finding). A dotted
+    // import (JVM `import com.example.OtherClass`) also contributes its LAST
+    // segment — the simple name Java/Kotlin code uses in `OtherClass::method`
+    // references.
     const SIMPLE_NAME = /^[A-Za-z_$][A-Za-z0-9_$]*$/;
+    const DOTTED_NAME = /^[A-Za-z_$][A-Za-z0-9_$.]*\.([A-Za-z_$][A-Za-z0-9_$]*)$/;
     const importedNames = new Set<string>();
     for (const r of this.unresolvedReferences) {
-      if (r.referenceKind === 'imports' && SIMPLE_NAME.test(r.referenceName)) {
+      if (r.referenceKind !== 'imports') continue;
+      if (SIMPLE_NAME.test(r.referenceName)) {
         importedNames.add(r.referenceName);
+      } else {
+        const dotted = r.referenceName.match(DOTTED_NAME);
+        if (dotted) importedNames.add(dotted[1]!);
       }
     }
 
@@ -468,21 +483,37 @@ export class TreeSitterExtractor {
       ) {
         continue;
       }
-      // C-family file-scope initializers skip the gate (constant-expression
-      // context — a bare identifier there is a function address, never a
-      // variable; see FnRefSpec.ungatedModes). Local initializers and
-      // everything else require a same-file/import match.
-      const skipGate = ungated?.has(c.mode) === true && atFileScope;
-      // Qualified C++ member-pointers (`Widget::on_click`) and TS/JS
-      // `this.<member>` candidates gate on the member name; everything else
-      // on the full name.
-      const gateName = c.name.startsWith('this.')
-        ? c.name.slice(5)
-        : c.name.includes('::')
-          ? c.name.slice(c.name.lastIndexOf('::') + 2)
-          : c.name;
-      if (!skipGate && !definedHere.has(gateName) && !importedNames.has(gateName)) {
-        continue;
+      // Gate policy by candidate shape:
+      //  - `this.<member>`: ALWAYS flush — the member may be inherited from a
+      //    class in another file (definedHere can't see it), volume is
+      //    naturally bounded by real `this.X` expressions, and resolution is
+      //    strictly class-scoped (own members or the validated supertype
+      //    pass), so nothing fuzzy can leak.
+      //  - `Scope::member` (C++ member-pointers, Java/Kotlin type-qualified
+      //    method refs): the SCOPE name must be a type defined here or an
+      //    imported name (covers `OtherClass::method` cross-file), or the
+      //    member matches the plain gate (back-compat for C++ same-file).
+      //  - C-family file-scope initializers skip the gate entirely
+      //    (constant-expression context — see FnRefSpec.ungatedModes).
+      //  - everything else: name ∈ same-file functions/methods ∪ imports.
+      if (!c.name.startsWith('this.')) {
+        const skipGate = ungated?.has(c.mode) === true && atFileScope;
+        if (!skipGate) {
+          if (c.name.includes('::')) {
+            const scopeName = c.name.slice(0, c.name.indexOf('::'));
+            const memberName = c.name.slice(c.name.lastIndexOf('::') + 2);
+            if (
+              !definedTypes.has(scopeName) &&
+              !importedNames.has(scopeName) &&
+              !definedHere.has(memberName) &&
+              !importedNames.has(memberName)
+            ) {
+              continue;
+            }
+          } else if (!definedHere.has(c.name) && !importedNames.has(c.name)) {
+            continue;
+          }
+        }
       }
       const key = `${c.fromNodeId}|${c.name}`;
       if (seen.has(key)) continue;