fix(extraction): never fabricate an edge from a call-result receiver (#1748)

A member call whose receiver is itself a call — `d.setdefault(k, []).append(v)`,
`make().run()` — used to drop the receiver at extraction time, degrade to the
bare method name, and exact-match any top-level project symbol of that name
(Python and JavaScript/TypeScript). Keep the inner callee encoded as
`<inner>().<method>` in the TS extractor and native kernel; the name-matcher
refuses to guess for that shape (store-accessor exception only). Based on
#1692, rebased onto main after #1746. Fixes #1683.

Co-authored-by: Colby McHenry <colbymchenry@users.noreply.github.com>

__tests__/call-receiver-no-fabrication.test.ts

@@ -0,0 +1,81 @@
+/**
+ * A member call whose receiver is itself a call never fabricates an edge
+ * (#1683, #1681). `d.setdefault(k, []).append(v)` used to lose its receiver at
+ * extraction time, degrade to the bare `append`, and exact-match any top-level
+ * project function of that name — a call edge from an unrelated function,
+ * reproduced in Python and JavaScript alike. The receiver is now kept as
+ * `<inner>().<method>`, which nothing name-matches; the inner call resolves
+ * on its own as before.
+ */
+import { describe, it, expect, beforeAll, afterAll } from 'vitest';
+import * as fs from 'fs';
+import * as os from 'os';
+import * as path from 'path';
+import { CodeGraph } from '../src';
+import { extractFromSource } from '../src/extraction';
+import { initGrammars, loadAllGrammars } from '../src/extraction/grammars';
+
+let dir: string;
+let cg: CodeGraph;
+
+beforeAll(async () => {
+  await initGrammars();
+  await loadAllGrammars();
+  dir = fs.mkdtempSync(path.join(os.tmpdir(), 'cg-1683-'));
+  fs.mkdirSync(path.join(dir, 'py'));
+  fs.mkdirSync(path.join(dir, 'js'));
+  fs.writeFileSync(path.join(dir, 'py', '__init__.py'), '');
+  fs.writeFileSync(
+    path.join(dir, 'py', 'collect.py'),
+    'def append(item):\n    return item\n\ndef get(key):\n    return key\n\ndef make():\n    return {}\n\n' +
+      'def bucket(d, k, v):\n    d.setdefault(k, []).append(v)\n    return d.items().get(k)\n\n' +
+      'def fresh():\n    return make().get("x")\n'
+  );
+  fs.writeFileSync(
+    path.join(dir, 'js', 'collect.js'),
+    'function append(item) { return item; }\nfunction run() { return 1; }\nfunction make() { return {}; }\n' +
+      'function bucket(d, k, v) { d.setdefault(k, []).append(v); make().run(); (0, make)().run(); }\n' +
+      'module.exports = { append, run, make, bucket };\n'
+  );
+  cg = CodeGraph.initSync(dir);
+  await cg.indexAll();
+});
+
+afterAll(() => {
+  cg.destroy();
+  fs.rmSync(dir, { recursive: true, force: true });
+});
+
+const fn = (name: string, file: string) => cg.getNodesByName(name).find((n) => n.kind === 'function' && n.filePath.endsWith(file))!;
+const calleesOf = (name: string, file: string) =>
+  cg.getCallees(fn(name, file).id).filter(({ edge }) => edge.kind === 'calls').map(({ node }) => node.name).sort();
+// Callers through `calls` edges only — a `module.exports = { run }` value reference is not a call.
+const callersOf = (name: string, file: string) =>
+  cg.getCallers(fn(name, file).id).filter(({ edge }) => edge.kind === 'calls').map(({ node }) => node.name);
+
+describe('call-expression receivers (#1683)', () => {
+  it('Python: no edge from a call-result receiver to a same-named top-level function', () => {
+    expect(calleesOf('bucket', 'collect.py')).toEqual([]);
+    expect(callersOf('append', 'collect.py')).toEqual([]);
+    expect(callersOf('get', 'collect.py')).toEqual([]);
+    // The inner call still resolves on its own; `.get` on its unknown product does not.
+    expect(calleesOf('fresh', 'collect.py')).toEqual(['make']);
+  });
+
+  it('JavaScript: the same shape, and the inner call keeps its edge', () => {
+    expect(callersOf('append', 'collect.js')).toEqual([]);
+    // `make().run()` — what `make` returns is unknown, so `run` is not guessed.
+    expect(callersOf('run', 'collect.js')).toEqual([]);
+    expect(calleesOf('bucket', 'collect.js')).toEqual(['make']);
+  });
+
+  it('encodes the receiver as `<inner>().<method>` and drops a receiver with no static callee', () => {
+    const r = extractFromSource('src/x.js', 'function f(d) { d.setdefault("k", []).append(1); make().run(); (0, make)().run(); arr[0]().go(); }');
+    const names = r.unresolvedReferences.filter((u) => u.referenceKind === 'calls').map((u) => u.referenceName).sort();
+    // `(0, make)` and `arr[0]` are the inner calls' own refs, unchanged; their chains are dropped.
+    expect(names).toEqual(['(0, make)', 'arr[0]', 'd.setdefault', 'd.setdefault().append', 'make', 'make().run']);
+    const py = extractFromSource('x.py', 'def f(d):\n    d.setdefault("k", []).append(1)\n    d.items().get(2)\n');
+    expect(py.unresolvedReferences.filter((u) => u.referenceKind === 'calls').map((u) => u.referenceName).sort())
+      .toEqual(['d.items', 'd.items().get', 'd.setdefault', 'd.setdefault().append']);
+  });
+});

__tests__/fixtures/kernel-parity/torture.js

@@ -73,3 +73,12 @@ export default {
     },
   },
 };
+
+// --- call-expression receivers (#1683) ----------------------------------------
+function bucketChains(d, k, v) {
+  d.setdefault(k, []).append(v);
+  make().run();
+  (0, make)().run();
+  arr[0]().go();
+  obj.make().run().again();
+}

__tests__/fixtures/kernel-parity/torture.py

@@ -47,3 +47,12 @@ def shadowed():
 
 handlers = {"recv": target_cb}
 callbacks = [target_cb, view]
+
+
+# --- call receivers (#1683) ---------------------------------------------------
+def bucket_chains(d, k, v):
+    d.setdefault(k, []).append(v)
+    d.items().get(k)
+    make().run()
+    (lambda: make)()().run()
+    obj.make().run().again()

__tests__/object-literal-methods.test.ts

@@ -55,7 +55,10 @@ describe('object-literal method extraction', () => {
     // so an in-store calls edge will resolve once the pipeline runs.
     const fetchUser = result.nodes.find((n) => n.name === 'fetchUser')!;
     const fetchUserRefs = result.unresolvedReferences.filter((r) => r.fromNodeId === fetchUser.id);
-    expect(fetchUserRefs.map((r) => r.referenceName)).toContain('reset');
+    // `get().reset()` keeps its call receiver (#1683): the ref is the chain
+    // `get().reset`, which the resolver binds to the store's own `reset`.
+    expect(fetchUserRefs.map((r) => r.referenceName)).toContain('get().reset');
+    expect(fetchUserRefs.map((r) => r.referenceName)).not.toContain('reset');
 
     // The action's body wasn't mis-attributed to the file scope (the reason we
     // skip the generic body-visit for the store-factory call).