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/resolution/index.ts

@@ -207,6 +207,11 @@ export class ReferenceResolver {
   // once implements/extends edges exist, to resolve methods on a supertype the
   // receiver conforms to (#750).
   private deferredChainRefs: UnresolvedRef[] = [];
+  // `this.<member>` function-as-value refs whose member is NOT on the
+  // enclosing class itself — possibly inherited. Collected in-memory for the
+  // same reason as deferredChainRefs and drained by
+  // resolveDeferredThisMemberRefs once implements/extends edges exist (#808).
+  private deferredThisMemberRefs: UnresolvedRef[] = [];
   // Per-`.razor`/`.cshtml`-file `@using` namespace set (own directives + folder
   // `_Imports.razor`, cascading to the project root). Used to disambiguate a
   // markup type ref to the right C# namespace.
@@ -422,6 +427,10 @@ export class ReferenceResolver {
         return result;
       },
 
+      getNodeById: (id: string) => {
+        return this.queries.getNodeById(id);
+      },
+
       getSupertypes: (typeName: string, language) => {
         // Union the `implements`/`extends` targets of every same-named type node.
         // Matching by simple name (not id) reconciles a type declared in one node
@@ -1214,7 +1223,13 @@ export class ReferenceResolver {
           n.filePath === ref.filePath &&
           n.id !== ref.fromNodeId
       );
-    if (candidates.length === 0) return null;
+    if (candidates.length === 0) {
+      // Not on the class itself — possibly INHERITED. implements/extends
+      // edges don't exist yet in this pass, so retry in the supertype pass
+      // (resolveDeferredThisMemberRefs) instead of giving up.
+      this.deferredThisMemberRefs.push(ref);
+      return null;
+    }
     const target = candidates.reduce((a, b) => (a.startLine <= b.startLine ? a : b));
     return {
       original: ref,
@@ -1224,6 +1239,80 @@ export class ReferenceResolver {
     };
   }
 
+  /**
+   * Second pass for `this.<member>` refs whose member wasn't on the enclosing
+   * class itself (#808): once implements/extends edges exist, walk the
+   * class's supertypes (transitively, depth-capped) and resolve the member on
+   * the nearest one that declares it — `this.handleSubmit` registered in a
+   * subclass resolves to `FormBase::handleSubmit`. Validated targets only
+   * (function/method kind, same language family); no match → no edge.
+   * Mirrors resolveChainedCallsViaConformance's lifecycle. Returns the number
+   * of newly-created edges.
+   */
+  resolveDeferredThisMemberRefs(): number {
+    const deferred = this.deferredThisMemberRefs;
+    this.deferredThisMemberRefs = [];
+    if (deferred.length === 0) return 0;
+
+    this.clearCaches();
+    const resolved: ResolvedRef[] = [];
+    for (const ref of deferred) {
+      const member = ref.referenceName.slice('this.'.length);
+      const fromNode = this.queries.getNodeById(ref.fromNodeId);
+      if (!fromNode || !member) continue;
+      const sep = fromNode.qualifiedName.lastIndexOf('::');
+      if (sep <= 0) continue;
+      const classPrefix = fromNode.qualifiedName.slice(0, sep);
+      const className = classPrefix.includes('::')
+        ? classPrefix.slice(classPrefix.lastIndexOf('::') + 2)
+        : classPrefix;
+
+      // BFS up the supertype graph by simple name.
+      const seen = new Set<string>([className]);
+      let frontier = this.context.getSupertypes?.(className, ref.language) ?? [];
+      let target: Node | null = null;
+      for (let depth = 0; depth < 5 && frontier.length > 0 && !target; depth++) {
+        const next: string[] = [];
+        for (const superName of frontier) {
+          if (seen.has(superName)) continue;
+          seen.add(superName);
+          const members = this.context
+            .getNodesByName(member)
+            .filter(
+              (n) =>
+                (n.kind === 'function' || n.kind === 'method') &&
+                sameLanguageFamily(n.language, ref.language) &&
+                (n.qualifiedName === `${superName}::${member}` ||
+                  n.qualifiedName.endsWith(`::${superName}::${member}`))
+            );
+          if (members.length > 0) {
+            target = members.reduce((a, b) => (a.startLine <= b.startLine ? a : b));
+            break;
+          }
+          next.push(...(this.context.getSupertypes?.(superName, ref.language) ?? []));
+        }
+        frontier = next;
+      }
+
+      if (target) {
+        resolved.push({
+          original: ref,
+          targetNodeId: target.id,
+          confidence: 0.85,
+          resolvedBy: 'function-ref',
+        });
+      }
+    }
+    if (resolved.length === 0) return 0;
+
+    const edges = this.createEdges(resolved);
+    if (edges.length > 0) {
+      this.queries.insertEdges(edges);
+      this.clearCaches();
+    }
+    return edges.length;
+  }
+
   private gateLanguage(result: ResolvedRef | null, ref: UnresolvedRef): ResolvedRef | null {
     if (!result) return result;
     const tgt = this.getLanguageFromNodeId(result.targetNodeId);

src/resolution/name-matcher.ts

@@ -227,7 +227,7 @@ export function matchFunctionRef(
     };
   }
 
-  const candidates = context
+  let candidates = context
     .getNodesByName(ref.referenceName)
     .filter(
       (n) =>
@@ -237,6 +237,35 @@ export function matchFunctionRef(
     );
   if (candidates.length === 0) return null;
 
+  // Swift implicit-self: a bare identifier can name a METHOD only of the
+  // ENCLOSING type (`Button(action: handleTap)` written inside that type) —
+  // a same-named method on any OTHER class is a parameter collision
+  // (Alamofire: a `request` parameter resolving to EventMonitor::request).
+  // Scope method candidates to the from-symbol's type; top-level code has no
+  // implicit self, so method targets are excluded there entirely. Free
+  // functions are unaffected.
+  if (ref.language === 'swift' && candidates.some((n) => n.kind === 'method')) {
+    const fromNode = context.getNodeById?.(ref.fromNodeId);
+    const sep = fromNode ? fromNode.qualifiedName.lastIndexOf('::') : -1;
+    const classPrefix = fromNode && sep > 0 ? fromNode.qualifiedName.slice(0, sep) : null;
+    candidates = candidates.filter((n) => {
+      if (n.kind !== 'method') return true;
+      if (!classPrefix) return false;
+      const mSep = n.qualifiedName.lastIndexOf('::');
+      if (mSep <= 0) return false;
+      const methodPrefix = n.qualifiedName.slice(0, mSep);
+      // Accept exact-scope matches plus suffix relationships either way, so
+      // extension-declared members (`Holder::m`) still match a nested
+      // from-scope (`Module::Holder::wire`) and vice versa.
+      return (
+        methodPrefix === classPrefix ||
+        methodPrefix.endsWith(`::${classPrefix}`) ||
+        classPrefix.endsWith(`::${methodPrefix}`)
+      );
+    });
+    if (candidates.length === 0) return null;
+  }
+
   // Same-file definition wins — the extraction gate guarantees most survivors
   // have one, and it's the dominant C pattern (static callback registered in
   // a same-file ops struct).

src/resolution/types.ts

@@ -91,6 +91,13 @@ export interface ResolutionContext {
    * method). Optional so external/test contexts compile without it.
    */
   getSupertypes?(typeName: string, language: Language): string[];
+  /**
+   * Look up a node by its id. Lets matchers derive the FROM-symbol's
+   * enclosing-class scope (Swift implicit-self method scoping, `this.X`
+   * member resolution). Optional so external/test contexts compile
+   * without it.
+   */
+  getNodeById?(id: string): Node | null;
   /** Get cached import mappings for a file */
   getImportMappings(filePath: string, language: Language): ImportMapping[];
   /**