From aced4456cc3ea4c496cbabba8f8e5cd39dd2f30f Mon Sep 17 00:00:00 2001
From: Gergo Magyar <gergomagyar0@gmail.com>
Date: Thu, 30 Jul 2026 14:09:44 +0000
Subject: [PATCH] feat(languages): roll the receiver chain out to every emitter
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U8. Emission moves into one shared helper and is wired into all 14 language
emitters that build a capture node map.

The helper is language-free (AGENTS.md R6): its call gate reads the
`@reference.call.*` tag prefix — a vocabulary every language's `.scm` query
already shares — rather than a per-language tag list. Only TypeScript and
JavaScript defined a `CALL_TAGS` constant, so a per-language list would have
meant inventing one twelve times. `@reference.callable` is excluded by the
trailing dot: it marks a callable VALUE, not a call site.

It is also self-gating — a non-call match, an absent receiver, or a chain with
no nameable base each leave the match untouched — which is what makes it safe to
call before every `out.push(grouped)` in the emitters that have three or four
such paths.

Measured, not assumed:

    C++   svc->getUser()->save()    INVISIBLE-GAP → RESOLVES
    TS    (three shapes, from U10)                  RESOLVES

The C++ row is the one the plan flagged as having no fixture ANYWHERE:
`cpp-chain-call/` uses the value `.` form, which already worked. It now has one,
alongside a value-dot control proving the defect was the `->` base specifically.

A WRONG-EDGE REGRESSION, caught by the full multi-language suite and fixed.
Ruby `Factory.new.run` resolved correctly to `Factory#run` before this and to
`Product.run` after — a correct edge turned into a wrong one, which is precisely
the failure mode this work exists to avoid. Cause: `Factory.new` denotes an
INSTANCE of Factory, and the cascade encodes that through
`isConstructionSelectorHop` together with the class-constant test separating it
from an instance method genuinely named `new`. A chain step records only a name,
so the fold cannot make that distinction. It now declines any step matching the
language's construction selector and lets the cascade answer. Pinned by a unit
test.

PHP is a recorded residual, and the plan's named trap is NOT the cause. The trap
— a language whose node type is missing from `extractMixedChain`'s tables reads
as "didn't need it" when it cannot be measured — was checked directly against the
emitter, which emits `chain=1|$svc|cgetUser` correctly. The residual is that the
fold's base `$svc` does not bind in the PHP resolver. That is PHP binding-key
work, not a chain-layer defect.

Two incidental corrections to KTD6 fell out of that check. PHP's receiver capture
text is normalized to `$svc.getUser()` — dots, not `->` — so Case 0's "C-family
punctuation" gate does fire for PHP, contrary to the plan. And typing the fixture
parameter moved the PHP row from VISIBLE-GAP to INVISIBLE-GAP, because with a
type binding the cascade types the receiver but finds no member, so no drop is
recorded. An untyped fixture parameter had been reporting a language gap that was
really a fixture defect — the same error class as the untyped `$repo` control
caught earlier in this series.

The wiring inventory is pinned by a test. The helper being self-gating makes the
roster cheap to change silently, which is exactly why: a new entry means someone
wired a language without measuring it, a removed one means a refactor dropped
coverage. `cobol` and `vue` stay unwired — they group no capture node map, so
there is no receiver node to walk.

4367 tests green. The 7 remaining failures are all `*-captures-golden` snapshots,
which U9 regenerates once at the tip.
---
 .../bench/receiver-resolution/BASELINE.md     | 54 ++++++++++++
 .../bench/receiver-resolution/baseline.json   |  4 +-
 .../bench/receiver-resolution/measure.mjs     |  5 +-
 .../core/ingestion/languages/c/captures.ts    |  7 ++
 .../core/ingestion/languages/cpp/captures.ts  |  7 ++
 .../ingestion/languages/csharp/captures.ts    | 19 +++++
 .../core/ingestion/languages/dart/captures.ts | 19 +++++
 .../core/ingestion/languages/go/captures.ts   | 13 +++
 .../core/ingestion/languages/java/captures.ts | 19 +++++
 .../languages/javascript/captures.ts          |  7 ++
 .../ingestion/languages/kotlin/captures.ts    | 13 +++
 .../core/ingestion/languages/php/captures.ts  | 19 +++++
 .../ingestion/languages/python/captures.ts    | 25 ++++++
 .../core/ingestion/languages/ruby/captures.ts | 25 ++++++
 .../core/ingestion/languages/rust/captures.ts |  7 ++
 .../ingestion/languages/swift/captures.ts     | 25 ++++++
 .../languages/typescript/captures.ts          | 42 ++--------
 .../passes/compound-receiver.ts               | 12 +++
 .../utils/receiver-chain-captures.ts          | 68 +++++++++++++++
 .../receiver-chain-fold.test.ts               | 18 ++++
 .../receiver-chain-wiring.test.ts             | 83 +++++++++++++++++++
 21 files changed, 453 insertions(+), 38 deletions(-)
 create mode 100644 gitnexus/src/core/ingestion/utils/receiver-chain-captures.ts
 create mode 100644 gitnexus/test/unit/scope-resolution/receiver-chain-wiring.test.ts

diff --git a/gitnexus/bench/receiver-resolution/BASELINE.md b/gitnexus/bench/receiver-resolution/BASELINE.md
index 113583b499..49ac4979b5 100644
--- a/gitnexus/bench/receiver-resolution/BASELINE.md
+++ b/gitnexus/bench/receiver-resolution/BASELINE.md
@@ -188,3 +188,57 @@ must be read against the same bias.
   plain property path (`$this->repo`, `a::b`) never reaches the recorder.
 - `repos[0].save()` has neither `.` nor `(` in its receiver — same result.
 - `?.` and explicit type arguments produce no reference site at all.
+
+## U8 — per-language rollout
+
+Emission moved into one shared helper
+(`utils/receiver-chain-captures.ts`) and is wired into all 14 language
+emitters. The helper is language-free (R6): its call gate reads the
+`@reference.call.*` tag prefix, a vocabulary every language's `.scm` query
+shares, rather than a per-language tag list. It is self-gating — a non-call
+match, an absent receiver, or a chain with no nameable base all leave the match
+untouched — so inserting the call before every `out.push(grouped)` is safe even
+in the emitters that have three or four such paths.
+
+| Language | Shape | Before | After |
+|---|---|---|---|
+| TypeScript | `svc?.getUser().save()` | INVISIBLE-GAP | **RESOLVES** |
+| TypeScript | `svc!.getUser().save()` | VISIBLE-GAP | **RESOLVES** |
+| TypeScript | `svc.getTyped<User>().save()` | INVISIBLE-GAP | **RESOLVES** |
+| C++ | `svc->getUser()->save()` | INVISIBLE-GAP | **RESOLVES** |
+| C++ | `svc2.getUser()->save()` (control) | RESOLVES | RESOLVES |
+| PHP | `$svc->getUser()->save()` | VISIBLE-GAP | INVISIBLE-GAP |
+| PHP | `$this->repo->save()` (control) | RESOLVES | RESOLVES |
+
+The C++ row is the one the plan flagged as having **no fixture anywhere** —
+`cpp-chain-call/` uses the value `.` form, which already worked. It now has one,
+plus the value-dot control that proves the defect was the `->` base specifically.
+
+### PHP: a measured residual, with the trap checked
+
+PHP does **not** resolve yet, and the plan's named trap — a language whose node
+type is missing from `extractMixedChain`'s tables reads as "didn't need it" when
+it in fact cannot be measured — is **not** the cause. Checked directly against
+the emitter:
+
+```
+name=save   chain=1|$svc|cgetUser   recv=$svc.getUser()
+```
+
+The chain is minted correctly. The residual is that the fold's base, `$svc`,
+does not bind in the PHP resolver, so the fold returns `undefined` and the site
+falls through to the text cascade. That is PHP binding-key work, not a
+chain-layer defect, and it is left as a recorded residual rather than absorbed
+into this series.
+
+Two incidental corrections from that check, both to KTD6:
+
+- PHP's receiver capture text is normalized to `$svc.getUser()` — DOTS, not
+  `->`. So Case 0's "C-family punctuation" gate fires for PHP after all, which
+  is why the call chain was recorded as a VISIBLE-GAP to begin with.
+- Typing the fixture parameter (`function f(Service $svc)`) moved the row from
+  VISIBLE-GAP to INVISIBLE-GAP: with a type binding the cascade now types the
+  receiver but finds no member, so `compoundReceiverUnresolved` is false and no
+  drop is recorded. An untyped fixture parameter had been reporting a language
+  gap that was really a fixture defect — the same error class as the untyped
+  `$repo` control caught earlier.
diff --git a/gitnexus/bench/receiver-resolution/baseline.json b/gitnexus/bench/receiver-resolution/baseline.json
index 17adb49f74..d0c05d498a 100644
--- a/gitnexus/bench/receiver-resolution/baseline.json
+++ b/gitnexus/bench/receiver-resolution/baseline.json
@@ -10,11 +10,11 @@
       "indexElement": "INVISIBLE-GAP"
     },
     "php": {
-      "arrowCallChain": "VISIBLE-GAP",
+      "arrowCallChain": "INVISIBLE-GAP",
       "arrowPropertyPath": "RESOLVES"
     },
     "cpp": {
-      "pointerArrowChain": "INVISIBLE-GAP",
+      "pointerArrowChain": "RESOLVES",
       "valueDotChain": "RESOLVES"
     }
   },
diff --git a/gitnexus/bench/receiver-resolution/measure.mjs b/gitnexus/bench/receiver-resolution/measure.mjs
index 5864c0c4f0..e5611968b1 100644
--- a/gitnexus/bench/receiver-resolution/measure.mjs
+++ b/gitnexus/bench/receiver-resolution/measure.mjs
@@ -148,7 +148,10 @@ class Service {
 `,
     },
     header: `<?php\nrequire_once 'models.php';\n`,
-    wrap: (entry, body) => `function ${entry}($svc) {\n    ${body}\n}\n`,
+    // TYPED parameter. An untyped `$svc` has no type binding to resolve the
+    // chain's base against, which would make this row report a language gap
+    // that is really a fixture defect.
+    wrap: (entry, body) => `function ${entry}(Service $svc) {\n    ${body}\n}\n`,
     shapes: [
       {
         id: 'arrowCallChain',
diff --git a/gitnexus/src/core/ingestion/languages/c/captures.ts b/gitnexus/src/core/ingestion/languages/c/captures.ts
index 8253019357..14049375d2 100644
--- a/gitnexus/src/core/ingestion/languages/c/captures.ts
+++ b/gitnexus/src/core/ingestion/languages/c/captures.ts
@@ -11,6 +11,7 @@ import { parseSourceSafe } from '../../../tree-sitter/safe-parse.js';
 import { splitCInclude } from './import-decomposer.js';
 import { computeCDeclarationArity, computeCCallArity } from './arity-metadata.js';
 import { markStaticName } from './static-linkage.js';
+import { synthesizeReceiverChainCapture } from '../../utils/receiver-chain-captures.js';
 import {
   synthesizeCallableFlowCaptures,
   type CallableCaptureSignature,
@@ -163,6 +164,12 @@ export function emitCScopeCaptures(
       }
     }
 
+    // Structural receiver chain for a call whose receiver is itself an
+    // expression, so resolution can type it by folding over structure
+    // instead of re-parsing the receiver's source text. Self-gating: a
+    // non-call match, an absent receiver, or a chain with no nameable base
+    // all leave `grouped` untouched.
+    synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
     out.push(grouped);
   }
 
diff --git a/gitnexus/src/core/ingestion/languages/cpp/captures.ts b/gitnexus/src/core/ingestion/languages/cpp/captures.ts
index 069459470b..a13cba09db 100644
--- a/gitnexus/src/core/ingestion/languages/cpp/captures.ts
+++ b/gitnexus/src/core/ingestion/languages/cpp/captures.ts
@@ -24,6 +24,7 @@ import { extractCppTemplateConstraints } from './constraint-extractor.js';
 import { captureCppMemberLookupFacts } from './member-lookup.js';
 import { CPP_BRACED_INIT_TYPE_PREFIX } from './conversion-rank.js';
 import { logger } from '../../../logger.js';
+import { synthesizeReceiverChainCapture } from '../../utils/receiver-chain-captures.js';
 import {
   synthesizeCallableFlowCaptures,
   type CallableCaptureSignature,
@@ -604,6 +605,12 @@ export function emitCppScopeCaptures(
       }
     }
 
+    // Structural receiver chain for a call whose receiver is itself an
+    // expression, so resolution can type it by folding over structure
+    // instead of re-parsing the receiver's source text. Self-gating: a
+    // non-call match, an absent receiver, or a chain with no nameable base
+    // all leave `grouped` untouched.
+    synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
     out.push(grouped);
   }
 
diff --git a/gitnexus/src/core/ingestion/languages/csharp/captures.ts b/gitnexus/src/core/ingestion/languages/csharp/captures.ts
index fbe338adc0..cb1adb8de0 100644
--- a/gitnexus/src/core/ingestion/languages/csharp/captures.ts
+++ b/gitnexus/src/core/ingestion/languages/csharp/captures.ts
@@ -31,6 +31,7 @@ import { recordCacheHit, recordCacheMiss } from './cache-stats.js';
 import { getTreeSitterBufferSize } from '../../constants.js';
 import { parseSourceSafe } from '../../../tree-sitter/safe-parse.js';
 import { synthesizeCallableFlowCaptures } from '../../utils/callable-flow-captures.js';
+import { synthesizeReceiverChainCapture } from '../../utils/receiver-chain-captures.js';
 
 /** Declaration anchors that carry function-like arity metadata. */
 const FUNCTION_DECL_TAGS = [
@@ -159,6 +160,12 @@ export function emitCsharpScopeCaptures(
       }
       // Defensive fallback: emit the raw match so the extractor at
       // least sees an anchor, even without markers.
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
       continue;
     }
@@ -177,6 +184,12 @@ export function emitCsharpScopeCaptures(
     // the AST in code. Mirrors Python's `self`/`cls` synthesis on
     // `@scope.function` matches.
     if (grouped['@scope.function'] !== undefined) {
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
       const fnNode = nodeIfType(nodeMap['@scope.function'], ...FUNCTION_NODE_TYPES);
       if (fnNode !== null) {
@@ -287,6 +300,12 @@ export function emitCsharpScopeCaptures(
       }
     }
 
+    // Structural receiver chain for a call whose receiver is itself an
+    // expression, so resolution can type it by folding over structure
+    // instead of re-parsing the receiver's source text. Self-gating: a
+    // non-call match, an absent receiver, or a chain with no nameable base
+    // all leave `grouped` untouched.
+    synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
     out.push(grouped);
 
     // Synthesize primary-constructor declarations on class/record
diff --git a/gitnexus/src/core/ingestion/languages/dart/captures.ts b/gitnexus/src/core/ingestion/languages/dart/captures.ts
index 6587a7302d..3157c08419 100644
--- a/gitnexus/src/core/ingestion/languages/dart/captures.ts
+++ b/gitnexus/src/core/ingestion/languages/dart/captures.ts
@@ -46,6 +46,7 @@ import { encodeMarker } from '../../utils/heritage-marker.js';
 import { DART_BUILT_INS } from './built-ins.js';
 import { synthesizeCallableFlowCaptures } from '../../utils/callable-flow-captures.js';
 import { preprocessDartExtensionTypes } from './extension-type-preprocess.js';
+import { synthesizeReceiverChainCapture } from '../../utils/receiver-chain-captures.js';
 
 const FUNCTION_DECL_TAGS = [
   '@declaration.function',
@@ -155,6 +156,12 @@ export function emitDartScopeCaptures(
       const bodyNode = findFunctionBody(declNode);
 
       attachArityMetadata(grouped, declNode);
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
 
       if (bodyNode !== null) {
@@ -181,6 +188,12 @@ export function emitDartScopeCaptures(
           fieldType,
         );
       }
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
       if (fieldType !== null) {
         out.push({
@@ -192,6 +205,12 @@ export function emitDartScopeCaptures(
       continue;
     }
 
+    // Structural receiver chain for a call whose receiver is itself an
+    // expression, so resolution can type it by folding over structure
+    // instead of re-parsing the receiver's source text. Self-gating: a
+    // non-call match, an absent receiver, or a chain with no nameable base
+    // all leave `grouped` untouched.
+    synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
     out.push(grouped);
   }
 
diff --git a/gitnexus/src/core/ingestion/languages/go/captures.ts b/gitnexus/src/core/ingestion/languages/go/captures.ts
index 0179c3d1e2..ffc624c877 100644
--- a/gitnexus/src/core/ingestion/languages/go/captures.ts
+++ b/gitnexus/src/core/ingestion/languages/go/captures.ts
@@ -14,6 +14,7 @@ import { synthesizeGoTypeBindings, extractSimpleTypeNameText } from './type-bind
 import { getTreeSitterBufferSize } from '../../constants.js';
 import { parseSourceSafe } from '../../../tree-sitter/safe-parse.js';
 import { synthesizeCallableFlowCaptures } from '../../utils/callable-flow-captures.js';
+import { synthesizeReceiverChainCapture } from '../../utils/receiver-chain-captures.js';
 
 const GO_CALLABLE_CAPTURE_OPTIONS = {
   functionNodeTypes: new Set(['function_declaration', 'method_declaration', 'func_literal']),
@@ -155,6 +156,12 @@ export function emitGoScopeCaptures(
           );
         }
       }
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
       continue;
     }
@@ -176,6 +183,12 @@ export function emitGoScopeCaptures(
       }
     }
 
+    // Structural receiver chain for a call whose receiver is itself an
+    // expression, so resolution can type it by folding over structure
+    // instead of re-parsing the receiver's source text. Self-gating: a
+    // non-call match, an absent receiver, or a chain with no nameable base
+    // all leave `grouped` untouched.
+    synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
     out.push(grouped);
   }
 
diff --git a/gitnexus/src/core/ingestion/languages/java/captures.ts b/gitnexus/src/core/ingestion/languages/java/captures.ts
index 1314dd5bc6..dd463c83e7 100644
--- a/gitnexus/src/core/ingestion/languages/java/captures.ts
+++ b/gitnexus/src/core/ingestion/languages/java/captures.ts
@@ -43,6 +43,7 @@ import { captureJavaPackageFact } from './package-facts.js';
 import { synthesizeCallableFlowCaptures } from '../../utils/callable-flow-captures.js';
 import { captureJavaSpringConfigConsumerFacts } from './spring-config-bindings.js';
 import { captureJavaSpringDiClassFact, type JavaSpringDiClassFact } from './spring-di.js';
+import { synthesizeReceiverChainCapture } from '../../utils/receiver-chain-captures.js';
 import {
   captureJavaSpringConditionalFacts,
   type JavaSpringConditionalFact,
@@ -204,6 +205,12 @@ export function emitJavaScopeCaptures(
           continue;
         }
       }
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
       continue;
     }
@@ -257,6 +264,12 @@ export function emitJavaScopeCaptures(
     // Synthesize `this` / `super` receiver type-bindings on every
     // instance method-like.
     if (grouped['@scope.function'] !== undefined) {
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
       // `@scope.function` is captured directly on the method/constructor node.
       const fnNode = findFunctionNode(nodeMap['@scope.function']);
@@ -348,6 +361,12 @@ export function emitJavaScopeCaptures(
       }
     }
 
+    // Structural receiver chain for a call whose receiver is itself an
+    // expression, so resolution can type it by folding over structure
+    // instead of re-parsing the receiver's source text. Self-gating: a
+    // non-call match, an absent receiver, or a chain with no nameable base
+    // all leave `grouped` untouched.
+    synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
     out.push(grouped);
   }
 
diff --git a/gitnexus/src/core/ingestion/languages/javascript/captures.ts b/gitnexus/src/core/ingestion/languages/javascript/captures.ts
index 2ce0561dc5..b0eed8d687 100644
--- a/gitnexus/src/core/ingestion/languages/javascript/captures.ts
+++ b/gitnexus/src/core/ingestion/languages/javascript/captures.ts
@@ -48,6 +48,7 @@ import {
 import { getTreeSitterBufferSize } from '../../constants.js';
 import { parseSourceSafe } from '../../../tree-sitter/safe-parse.js';
 import { synthesizeCallableFlowCaptures } from '../../utils/callable-flow-captures.js';
+import { synthesizeReceiverChainCapture } from '../../utils/receiver-chain-captures.js';
 import {
   deriveDefaultExportHocName,
   isBlockedDefaultExportHoc,
@@ -997,6 +998,12 @@ export function emitJsScopeCaptures(
       }
     }
 
+    // Structural receiver chain for a call whose receiver is itself an
+    // expression, so resolution can type it by folding over structure
+    // instead of re-parsing the receiver's source text. Self-gating: a
+    // non-call match, an absent receiver, or a chain with no nameable base
+    // all leave `grouped` untouched.
+    synthesizeReceiverChainCapture(grouped, groupedNodes['@reference.receiver']);
     out.push(grouped);
 
     // Synthesize `this` receiver type-bindings on class member functions.
diff --git a/gitnexus/src/core/ingestion/languages/kotlin/captures.ts b/gitnexus/src/core/ingestion/languages/kotlin/captures.ts
index 657e6bcb66..00868c1743 100644
--- a/gitnexus/src/core/ingestion/languages/kotlin/captures.ts
+++ b/gitnexus/src/core/ingestion/languages/kotlin/captures.ts
@@ -26,6 +26,7 @@ import {
 import { captureKotlinPackageFact } from './package-facts.js';
 import { synthesizeCallableFlowCaptures } from '../../utils/callable-flow-captures.js';
 import { captureKotlinSpringDiClassFact, type KotlinSpringDiClassFact } from './spring-di.js';
+import { synthesizeReceiverChainCapture } from '../../utils/receiver-chain-captures.js';
 import {
   captureKotlinSpringConditionalFacts,
   type KotlinSpringConditionalFact,
@@ -246,6 +247,12 @@ export function emitKotlinScopeCaptures(
     }
 
     if (grouped['@scope.function'] !== undefined) {
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, groupedNodes['@reference.receiver']);
       out.push(grouped);
       const fnNode = nodeIfType(groupedNodes['@scope.function'], 'function_declaration');
       if (fnNode !== null) {
@@ -303,6 +310,12 @@ export function emitKotlinScopeCaptures(
       }
     }
 
+    // Structural receiver chain for a call whose receiver is itself an
+    // expression, so resolution can type it by folding over structure
+    // instead of re-parsing the receiver's source text. Self-gating: a
+    // non-call match, an absent receiver, or a chain with no nameable base
+    // all leave `grouped` untouched.
+    synthesizeReceiverChainCapture(grouped, groupedNodes['@reference.receiver']);
     out.push(grouped);
 
     const extensionFallback = extensionFreeCallFallback(grouped, groupedNodes);
diff --git a/gitnexus/src/core/ingestion/languages/php/captures.ts b/gitnexus/src/core/ingestion/languages/php/captures.ts
index 7e3ce5b150..de7e0a8c7d 100644
--- a/gitnexus/src/core/ingestion/languages/php/captures.ts
+++ b/gitnexus/src/core/ingestion/languages/php/captures.ts
@@ -46,6 +46,7 @@ import { recordCacheHit, recordCacheMiss } from './cache-stats.js';
 import { getTreeSitterBufferSize } from '../../constants.js';
 import { parseSourceSafe } from '../../../tree-sitter/safe-parse.js';
 import { synthesizeCallableFlowCaptures } from '../../utils/callable-flow-captures.js';
+import { synthesizeReceiverChainCapture } from '../../utils/receiver-chain-captures.js';
 
 type SyntaxNode = ReturnType<ReturnType<typeof getPhpParser>['parse']>['rootNode'];
 
@@ -228,6 +229,12 @@ export function emitPhpScopeCaptures(
         }
       }
       // Defensive fallback: emit the raw match.
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
       continue;
     }
@@ -235,6 +242,12 @@ export function emitPhpScopeCaptures(
     // Synthesize `$this` / `parent` receiver type-bindings on every
     // non-static method-like. Mirrors C#'s `this` / `base` synthesis.
     if (grouped['@scope.function'] !== undefined) {
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
       const fnNode = nodeIfType(nodeMap['@scope.function'], ...FUNCTION_NODE_TYPES);
       if (fnNode !== null) {
@@ -338,6 +351,12 @@ export function emitPhpScopeCaptures(
       }
     }
 
+    // Structural receiver chain for a call whose receiver is itself an
+    // expression, so resolution can type it by folding over structure
+    // instead of re-parsing the receiver's source text. Self-gating: a
+    // non-call match, an absent receiver, or a chain with no nameable base
+    // all leave `grouped` untouched.
+    synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
     out.push(grouped);
   }
 
diff --git a/gitnexus/src/core/ingestion/languages/python/captures.ts b/gitnexus/src/core/ingestion/languages/python/captures.ts
index 2a196bb329..0b0e981156 100644
--- a/gitnexus/src/core/ingestion/languages/python/captures.ts
+++ b/gitnexus/src/core/ingestion/languages/python/captures.ts
@@ -35,6 +35,7 @@ import { getTreeSitterBufferSize } from '../../constants.js';
 import { parseSourceSafe } from '../../../tree-sitter/safe-parse.js';
 import { pythonFunctionDefinitionLabel } from './simple-hooks.js';
 import { synthesizeCallableFlowCaptures } from '../../utils/callable-flow-captures.js';
+import { synthesizeReceiverChainCapture } from '../../utils/receiver-chain-captures.js';
 
 const PYTHON_CALLABLE_CAPTURE_OPTIONS = {
   functionNodeTypes: new Set(['function_definition', 'lambda']),
@@ -120,12 +121,24 @@ export function emitPythonScopeCaptures(
         for (const piece of splitImportStatement(stmtNode)) out.push(piece);
       } else {
         // Defensive fallback: emit the raw match.
+        // Structural receiver chain for a call whose receiver is itself an
+        // expression, so resolution can type it by folding over structure
+        // instead of re-parsing the receiver's source text. Self-gating: a
+        // non-call match, an absent receiver, or a chain with no nameable base
+        // all leave `grouped` untouched.
+        synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
         out.push(grouped);
       }
       continue;
     }
 
     if (grouped['@scope.function'] !== undefined) {
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
       // `@scope.function` is captured directly on the `function_definition`
       // node (query: `(function_definition) @scope.function`), so it IS the
@@ -183,10 +196,22 @@ export function emitPythonScopeCaptures(
           );
         }
       }
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
       continue;
     }
 
+    // Structural receiver chain for a call whose receiver is itself an
+    // expression, so resolution can type it by folding over structure
+    // instead of re-parsing the receiver's source text. Self-gating: a
+    // non-call match, an absent receiver, or a chain with no nameable base
+    // all leave `grouped` untouched.
+    synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
     out.push(grouped);
   }
 
diff --git a/gitnexus/src/core/ingestion/languages/ruby/captures.ts b/gitnexus/src/core/ingestion/languages/ruby/captures.ts
index ea4c5cf6ca..285e52afa2 100644
--- a/gitnexus/src/core/ingestion/languages/ruby/captures.ts
+++ b/gitnexus/src/core/ingestion/languages/ruby/captures.ts
@@ -15,6 +15,7 @@ import { parseSourceSafe } from '../../../tree-sitter/safe-parse.js';
 import { splitQualifiedName } from '../../utils/qualified-name.js';
 import { encodeMarker } from '../../utils/heritage-marker.js';
 import { synthesizeCallableFlowCaptures } from '../../utils/callable-flow-captures.js';
+import { synthesizeReceiverChainCapture } from '../../utils/receiver-chain-captures.js';
 
 const FUNCTION_NODE_TYPES = ['method', 'singleton_method'] as const;
 const HERITAGE_CALL_NAMES: ReadonlySet<string> = new Set(['include', 'extend', 'prepend']);
@@ -147,6 +148,12 @@ export function emitRubyScopeCaptures(
           continue;
         }
       }
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
       continue;
     }
@@ -159,6 +166,12 @@ export function emitRubyScopeCaptures(
         const receiver = synthesizeRubyReceiverBinding(fnNode, enclosingNode);
         if (receiver !== null) out.push(receiver);
       }
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
       continue;
     }
@@ -204,6 +217,12 @@ export function emitRubyScopeCaptures(
           );
         }
       }
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
       continue;
     }
@@ -304,6 +323,12 @@ export function emitRubyScopeCaptures(
       }
     }
 
+    // Structural receiver chain for a call whose receiver is itself an
+    // expression, so resolution can type it by folding over structure
+    // instead of re-parsing the receiver's source text. Self-gating: a
+    // non-call match, an absent receiver, or a chain with no nameable base
+    // all leave `grouped` untouched.
+    synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
     out.push(grouped);
   }
 
diff --git a/gitnexus/src/core/ingestion/languages/rust/captures.ts b/gitnexus/src/core/ingestion/languages/rust/captures.ts
index cae5ee0034..ae15c99e26 100644
--- a/gitnexus/src/core/ingestion/languages/rust/captures.ts
+++ b/gitnexus/src/core/ingestion/languages/rust/captures.ts
@@ -13,6 +13,7 @@ import { synthesizeRustReceiverBinding } from './receiver-binding.js';
 import { getTreeSitterBufferSize } from '../../constants.js';
 import { parseSourceSafe } from '../../../tree-sitter/safe-parse.js';
 import { synthesizeCallableFlowCaptures } from '../../utils/callable-flow-captures.js';
+import { synthesizeReceiverChainCapture } from '../../utils/receiver-chain-captures.js';
 
 const RUST_CALLABLE_CAPTURE_OPTIONS = {
   functionNodeTypes: new Set(['function_item', 'closure_expression']),
@@ -197,6 +198,12 @@ export function emitRustScopeCaptures(
       }
     }
 
+    // Structural receiver chain for a call whose receiver is itself an
+    // expression, so resolution can type it by folding over structure
+    // instead of re-parsing the receiver's source text. Self-gating: a
+    // non-call match, an absent receiver, or a chain with no nameable base
+    // all leave `grouped` untouched.
+    synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
     out.push(grouped);
   }
 
diff --git a/gitnexus/src/core/ingestion/languages/swift/captures.ts b/gitnexus/src/core/ingestion/languages/swift/captures.ts
index cff4e13664..b9b111454a 100644
--- a/gitnexus/src/core/ingestion/languages/swift/captures.ts
+++ b/gitnexus/src/core/ingestion/languages/swift/captures.ts
@@ -50,6 +50,7 @@ import { recordCacheHit, recordCacheMiss } from './cache-stats.js';
 import { getTreeSitterBufferSize } from '../../constants.js';
 import { parseSourceSafe } from '../../../tree-sitter/safe-parse.js';
 import { synthesizeCallableFlowCaptures } from '../../utils/callable-flow-captures.js';
+import { synthesizeReceiverChainCapture } from '../../utils/receiver-chain-captures.js';
 
 /** Declaration anchors that carry function-like arity metadata. */
 const FUNCTION_DECL_TAGS = ['@declaration.method', '@declaration.constructor'] as const;
@@ -129,6 +130,12 @@ export function emitSwiftScopeCaptures(
           continue;
         }
       }
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped); // defensive fallback
       continue;
     }
@@ -174,6 +181,12 @@ export function emitSwiftScopeCaptures(
       const span = `${navNode.startIndex}-${navNode.endIndex}`;
       if (seenReadSpans.has(span)) continue;
       seenReadSpans.add(span);
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
       continue;
     }
@@ -236,6 +249,12 @@ export function emitSwiftScopeCaptures(
         ...FUNCTION_NODE_TYPES,
       );
       if (fnNodeForArity !== null) attachArityMetadata(grouped, fnNodeForArity);
+      // Structural receiver chain for a call whose receiver is itself an
+      // expression, so resolution can type it by folding over structure
+      // instead of re-parsing the receiver's source text. Self-gating: a
+      // non-call match, an absent receiver, or a chain with no nameable base
+      // all leave `grouped` untouched.
+      synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
       out.push(grouped);
 
       const recvNode = nodeIfType(nodeMap['@scope.function'], ...RECEIVER_NODE_TYPES);
@@ -296,6 +315,12 @@ export function emitSwiftScopeCaptures(
       }
     }
 
+    // Structural receiver chain for a call whose receiver is itself an
+    // expression, so resolution can type it by folding over structure
+    // instead of re-parsing the receiver's source text. Self-gating: a
+    // non-call match, an absent receiver, or a chain with no nameable base
+    // all leave `grouped` untouched.
+    synthesizeReceiverChainCapture(grouped, nodeMap['@reference.receiver']);
     out.push(grouped);
   }
 
diff --git a/gitnexus/src/core/ingestion/languages/typescript/captures.ts b/gitnexus/src/core/ingestion/languages/typescript/captures.ts
index 9770acc894..34146686a8 100644
--- a/gitnexus/src/core/ingestion/languages/typescript/captures.ts
+++ b/gitnexus/src/core/ingestion/languages/typescript/captures.ts
@@ -46,9 +46,8 @@ import {
 import { getTreeSitterBufferSize } from '../../constants.js';
 import { parseSourceSafe } from '../../../tree-sitter/safe-parse.js';
 import { synthesizeCallableFlowCaptures } from '../../utils/callable-flow-captures.js';
-import { extractMixedChain } from '../../utils/call-analysis.js';
-import { encodeReceiverChain } from '../../utils/receiver-chain-codec.js';
 import { synthesizeCjsModuleExports } from './cjs-module-exports.js';
+import { synthesizeReceiverChainCapture } from '../../utils/receiver-chain-captures.js';
 import {
   deriveDefaultExportHocName,
   isBlockedDefaultExportHoc,
@@ -496,39 +495,12 @@ export function emitTsScopeCaptures(
       }
     }
 
-    // Synthesize the compact receiver chain for a receiver that is itself an
-    // expression, so resolution can type it by folding over structure instead
-    // of re-parsing the receiver's source text.
-    //
-    // Emitted HERE rather than in the query: the receiver capture originates in
-    // several `.scm` patterns, and a query cannot call `extractMixedChain`.
-    //
-    // Gated on CALL_TAGS. Without that gate this fires on read, write and JSX
-    // receivers too, which pay the walk and the bytes for a field no call-site
-    // resolver will read.
-    //
-    // A chain is minted only when the walk reached a NAMEABLE base.
-    // `extractMixedChain` returns `baseReceiverName: undefined` when it stopped
-    // early — either it hit `MAX_CHAIN_DEPTH` or it could not read a step — and
-    // in both cases what it collected is a partial chain whose missing head is
-    // exactly what decides the final type. Encoding that would turn a receiver
-    // we cannot type into one we type WRONGLY, so those fall through to the
-    // existing text cascade instead.
-    const receiverChainNode = groupedNodes['@reference.receiver'];
-    if (receiverChainNode !== undefined && callAnchor !== undefined) {
-      const extracted = extractMixedChain(receiverChainNode);
-      if (extracted !== undefined && extracted.baseReceiverName !== undefined) {
-        const encoded = encodeReceiverChain(extracted.baseReceiverName, extracted.chain);
-        if (encoded !== undefined) {
-          grouped['@reference.receiver-chain'] = syntheticCapture(
-            '@reference.receiver-chain',
-            receiverChainNode,
-            encoded,
-          );
-        }
-      }
-    }
-
+    // Structural receiver chain for a call whose receiver is itself an
+    // expression, so resolution can type it by folding over structure
+    // instead of re-parsing the receiver's source text. Self-gating: a
+    // non-call match, an absent receiver, or a chain with no nameable base
+    // all leave `grouped` untouched.
+    synthesizeReceiverChainCapture(grouped, groupedNodes['@reference.receiver']);
     out.push(grouped);
 
     // Synthesize `this` receiver type-bindings on every function-like
diff --git a/gitnexus/src/core/ingestion/scope-resolution/passes/compound-receiver.ts b/gitnexus/src/core/ingestion/scope-resolution/passes/compound-receiver.ts
index 4f942bc806..0a3425777e 100644
--- a/gitnexus/src/core/ingestion/scope-resolution/passes/compound-receiver.ts
+++ b/gitnexus/src/core/ingestion/scope-resolution/passes/compound-receiver.ts
@@ -302,6 +302,18 @@ export function foldReceiverChain(
   if (current === undefined) return undefined;
 
   for (const step of chain.steps) {
+    // Construction is NOT an ordinary member lookup. `Factory.new` on a class
+    // constant denotes an instance of Factory, and the cascade already encodes
+    // that (`isConstructionSelectorHop`) along with the class-constant test that
+    // separates it from an instance method genuinely named `new`. The fold
+    // carries no such distinction — a chain step records a name, not whether its
+    // base was a class reference or a value — so folding one would resolve
+    // `Factory.new.run` against whatever member named `new` the lookup reaches
+    // first. That turned a correct edge into a WRONG one (Ruby
+    // `Factory.new.run` → `Product.run`), which is the failure mode this whole
+    // line of work exists to avoid. Decline and let the cascade answer.
+    if (options.constructionSyntax?.selector === step.name) return undefined;
+
     const next = typeOfMemberOnClass(current, step.name, scopes, index, options);
     if (next === undefined) return undefined;
     current = next;
diff --git a/gitnexus/src/core/ingestion/utils/receiver-chain-captures.ts b/gitnexus/src/core/ingestion/utils/receiver-chain-captures.ts
new file mode 100644
index 0000000000..687e687b26
--- /dev/null
+++ b/gitnexus/src/core/ingestion/utils/receiver-chain-captures.ts
@@ -0,0 +1,68 @@
+/**
+ * Synthesize `@reference.receiver-chain` for a call match whose receiver is
+ * itself an expression.
+ *
+ * Shared across every language emitter, and deliberately language-free (AGENTS.md
+ * R6): the call gate reads the `@reference.call.*` tag vocabulary, which is
+ * shared by every language's `.scm` query, rather than a per-language tag list.
+ *
+ * Lives in the emitter layer rather than the query because a `.scm` pattern
+ * cannot call `extractMixedChain`, and the receiver capture originates in
+ * several patterns per language.
+ */
+
+import type { Capture } from 'gitnexus-shared';
+
+import type { SyntaxNode } from './ast-helpers.js';
+import { syntheticCapture } from './ast-helpers.js';
+import { extractMixedChain } from './call-analysis.js';
+import { encodeReceiverChain } from './receiver-chain-codec.js';
+
+/** Tag prefix marking a match as a CALL. `@reference.callable` is deliberately
+ *  excluded by the trailing dot — it marks a callable VALUE, not a call site. */
+const CALL_TAG_PREFIX = '@reference.call.';
+
+/** Does this match represent a call? */
+function isCallMatch(grouped: Record<string, Capture>): boolean {
+  for (const tag of Object.keys(grouped)) {
+    if (tag.startsWith(CALL_TAG_PREFIX)) return true;
+  }
+  return false;
+}
+
+/**
+ * Add `@reference.receiver-chain` to `grouped` when the match is a call whose
+ * receiver decodes to a chain over a nameable base. Mutates `grouped` in place
+ * and returns nothing — mirroring how the other synthesized captures are added.
+ *
+ * Gated on the call tags: without that gate this fires on read, write and JSX
+ * receivers too, which pay the AST walk and the persisted bytes for a field no
+ * call-site resolver reads.
+ *
+ * A chain is minted ONLY when the walk reached a nameable base.
+ * `extractMixedChain` reports `baseReceiverName: undefined` whenever it stopped
+ * early — at `MAX_CHAIN_DEPTH`, or because a step could not be read — and what it
+ * collected then is a partial chain missing exactly the head that decides the
+ * final type. Encoding that would turn a receiver we cannot type into one we type
+ * WRONGLY, so those fall through to the resolver's existing text cascade.
+ */
+export function synthesizeReceiverChainCapture(
+  grouped: Record<string, Capture>,
+  receiverNode: SyntaxNode | undefined | null,
+): void {
+  if (receiverNode === undefined || receiverNode === null) return;
+  if (grouped['@reference.receiver-chain'] !== undefined) return;
+  if (!isCallMatch(grouped)) return;
+
+  const extracted = extractMixedChain(receiverNode);
+  if (extracted === undefined || extracted.baseReceiverName === undefined) return;
+
+  const encoded = encodeReceiverChain(extracted.baseReceiverName, extracted.chain);
+  if (encoded === undefined) return;
+
+  grouped['@reference.receiver-chain'] = syntheticCapture(
+    '@reference.receiver-chain',
+    receiverNode,
+    encoded,
+  );
+}
diff --git a/gitnexus/test/unit/scope-resolution/receiver-chain-fold.test.ts b/gitnexus/test/unit/scope-resolution/receiver-chain-fold.test.ts
index 52717a6961..f44d6a2223 100644
--- a/gitnexus/test/unit/scope-resolution/receiver-chain-fold.test.ts
+++ b/gitnexus/test/unit/scope-resolution/receiver-chain-fold.test.ts
@@ -112,4 +112,22 @@ describe('foldReceiverChain', () => {
   it('declines a truncated chain even though the producer refuses to mint one', () => {
     expect(fold('1|svc|cgetUser|~')).toBeUndefined();
   });
+
+  it('declines a construction-selector step and leaves it to the cascade', () => {
+    // `Factory.new` denotes an INSTANCE of Factory, not the result of looking up
+    // a member named `new`. The cascade encodes that, together with the
+    // class-constant test that separates it from an instance method genuinely
+    // named `new`; a chain step records only a name, so the fold cannot make the
+    // distinction and must not try. Folding it turned a correct Ruby edge
+    // (`Factory.new.run` → `Factory#run`) into a wrong one (`Product.run`).
+    const decoded = decodeReceiverChain('1|svc|cnew');
+    expect(decoded).toBeDefined();
+    expect(
+      foldReceiverChain(decoded!, ctx.inScope, ctx.scopes, ctx.index, {
+        fieldFallback: false,
+        hoistTypeBindingsToModule: true,
+        constructionSyntax: { selector: 'new' },
+      }),
+    ).toBeUndefined();
+  });
 });
diff --git a/gitnexus/test/unit/scope-resolution/receiver-chain-wiring.test.ts b/gitnexus/test/unit/scope-resolution/receiver-chain-wiring.test.ts
new file mode 100644
index 0000000000..e4d68ff696
--- /dev/null
+++ b/gitnexus/test/unit/scope-resolution/receiver-chain-wiring.test.ts
@@ -0,0 +1,83 @@
+/**
+ * Which language emitters synthesize `@reference.receiver-chain`.
+ *
+ * The helper is self-gating — a non-call match, an absent receiver, or a chain
+ * with no nameable base all leave the match untouched — so wiring a language
+ * costs nothing where the shape does not occur. That makes the inventory easy to
+ * change silently, which is exactly why it is pinned: a new entry means someone
+ * wired a language without measuring it, and a removed entry means a refactor
+ * quietly dropped coverage.
+ *
+ * Source-level rather than behavioural, because the thing being pinned IS the
+ * wiring: a behavioural check would pass for a language whose fixture happens to
+ * contain no chained receiver.
+ */
+
+import { describe, it, expect } from 'vitest';
+import { readFileSync, readdirSync } from 'node:fs';
+import path from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const LANGUAGES_DIR = path.resolve(
+  path.dirname(fileURLToPath(import.meta.url)),
+  '..',
+  '..',
+  '..',
+  'src',
+  'core',
+  'ingestion',
+  'languages',
+);
+
+function emittersCallingHelper(): string[] {
+  const out: string[] = [];
+  for (const entry of readdirSync(LANGUAGES_DIR, { withFileTypes: true })) {
+    if (!entry.isDirectory()) continue;
+    const captures = path.join(LANGUAGES_DIR, entry.name, 'captures.ts');
+    let source: string;
+    try {
+      source = readFileSync(captures, 'utf8');
+    } catch {
+      continue; // no captures.ts (cobol/vue emit through another path)
+    }
+    if (source.includes('synthesizeReceiverChainCapture(')) out.push(entry.name);
+  }
+  return out.sort();
+}
+
+describe('receiver-chain capture wiring inventory', () => {
+  it('is wired into exactly the emitters that build a capture node map', () => {
+    expect(emittersCallingHelper()).toEqual([
+      'c',
+      'cpp',
+      'csharp',
+      'dart',
+      'go',
+      'java',
+      'javascript',
+      'kotlin',
+      'php',
+      'python',
+      'ruby',
+      'rust',
+      'swift',
+      'typescript',
+    ]);
+  });
+
+  it('leaves emitters without a node map unwired', () => {
+    // These two do not group captures with their originating syntax nodes, so
+    // there is no receiver node to walk. Wiring them would need an emitter
+    // change, not a one-line call.
+    for (const language of ['cobol', 'vue'] as const) {
+      const captures = path.join(LANGUAGES_DIR, language, 'captures.ts');
+      let source = '';
+      try {
+        source = readFileSync(captures, 'utf8');
+      } catch {
+        continue;
+      }
+      expect(source, `${language} stays unwired`).not.toContain('synthesizeReceiverChainCapture(');
+    }
+  });
+});