Park Kotlin object member calls across a repo boundary (#3388)

The cross-file `_resolve_kotlin_member_calls` landed for #1698 binds
`Receiver.method()` only when the object/class the receiver names is declared
in the same build. When that declaration lives in another repository the pass
had the receiver name in hand and dropped the call anyway, so nothing about it
reached graph.json — the one artifact merge-graphs and global add read — and no
merge-time pass could recover what was never written down.

Park the call by name at that bail-out, the same mechanism Java/C++/C#/Swift
already use: only when the object is declared nowhere here (an ambiguous 2+ match
still fabricates nothing) and never for a builtin receiver. cross_repo_calls then
finishes the edge once the declaring repo joins the graph, gated on .kt/.kts so a
same-named declaration in another language cannot answer a Kotlin call.

Co-Authored-By: Claude Code <noreply@anthropic.com>

graphify/cross_repo_calls.py

@@ -42,6 +42,7 @@ _LANG_SUFFIXES: dict[str, frozenset[str]] = {
     "cpp": frozenset({".cpp", ".cc", ".cxx", ".hpp", ".hh", ".hxx", ".h", ".cu", ".cuh"}),
     "csharp": frozenset({".cs"}),
     "java": frozenset({".java"}),
+    "kotlin": frozenset({".kt", ".kts"}),
     "swift": frozenset({".swift"}),
 }
 

graphify/extract.py

@@ -6994,6 +6994,14 @@ def _resolve_kotlin_member_calls(
         callee = rc["callee"]
         caller = rc["caller_nid"]
         type_nids = types_by_name.get(receiver, [])
+        if not type_nids:
+            # Object/class declared nowhere here — usually in a repo this build does
+            # not contain, so park it for the merge (#3152/#3388). A builtin receiver
+            # (String.format, ...) never crosses a repo boundary.
+            if receiver not in _LANGUAGE_BUILTIN_GLOBALS:
+                _park_unresolved_member_call(
+                    node_by_id.get(caller), callee, receiver, "kotlin", rc)
+            continue
         if len(type_nids) != 1:
             continue
         wanted = f".{callee}"

tests/test_cross_repo_member_calls.py

@@ -6,8 +6,8 @@ type already in hand and nothing about it reached `graph.json` — the only arti
 `merge-graphs` and `global add` read. The two-repo graph was missing precisely the
 edges that make it a call graph.
 
-The Java, C++, C# and Swift resolvers now park those calls on the caller node and
-this pass finishes them after the merge. The cases below pin what it must NOT do
+The Java, C++, C#, Swift and Kotlin resolvers now park those calls on the caller
+node and this pass finishes them after the merge. The cases below pin what it must NOT do
 as much as what it must: the single-definition guard, the cross-repo-only scope,
 and the language guard are what keep it from fabricating an edge from a name
 collision.
@@ -45,6 +45,7 @@ needs_java = _needs("tree_sitter_java")
 needs_cpp = _needs("tree_sitter_cpp")
 needs_csharp = _needs("tree_sitter_c_sharp")
 needs_swift = _needs("tree_sitter_swift")
+needs_kotlin = _needs("tree_sitter_kotlin")
 
 
 def _caller(repo: str, parked: list[dict], node_id: str = "app_run",
@@ -374,6 +375,14 @@ def test_a_java_build_parks_the_call_and_the_merge_finishes_it(tmp_path: Path):
         ("src/Greeter.swift", "class Greeter { func greet() {} }\n"),
         marks=needs_swift, id="swift-property-receiver",
     ),
+    pytest.param(
+        # The object-qualified shape the Kotlin resolver answers: `Greeter.greet()`
+        # names the object singleton explicitly, and only the other repo declares it.
+        "kotlin", "greet",
+        ("src/App.kt", "fun run() { Greeter.greet() }\n"),
+        ("src/Greeter.kt", "object Greeter { fun greet() {} }\n"),
+        marks=needs_kotlin, id="kotlin-object-receiver",
+    ),
 ])
 def test_each_language_parks_the_call_and_the_merge_finishes_it(
     tmp_path: Path, lang: str, callee: str, app_file: tuple[str, str],