fix(objc): remap the field->type table keys with the ids they hold (#3150)

The Objective-C field->type table is keyed by class node id, but the id-carrier rewrites
(prefix strip, symbol canonicalisation, cache portability round-trip) never remapped those
keys, so after graphify update the keys went stale and every self.field / obj.field method
call missed resolution. Remap the table keys alongside the existing id remaps (in-process
and in the cache round-trip); a dropped key can only cost a missed edge, never a phantom.

graphify/cache.py

@@ -788,12 +788,30 @@ def _portability_anchors(path: "str | Path", root: "str | Path") -> tuple[list[s
     return id_anchors, id_restore, path_anchors, str(root_resolved)
 
 
+def _rewrite_id_keyed_table_keys(payload: object, fn) -> None:
+    """Apply ``fn`` to objc_field_types["tables"] KEYS (#3150).
+
+    That table is the one extractor bucket keyed BY node id, which
+    :func:`_rewrite_strings` deliberately never touches - so a cached ObjC
+    shard replayed under another root kept absolute-derived class ids as keys
+    while the node ids themselves were re-anchored, and the receiver-typing
+    pass missed every class.
+    """
+    ft = payload.get("objc_field_types") if isinstance(payload, dict) else None
+    tables = ft.get("tables") if isinstance(ft, dict) else None
+    if isinstance(tables, dict):
+        ft["tables"] = {
+            (fn(k) if isinstance(k, str) else k): v for k, v in tables.items()
+        }
+
+
 def _rewrite_strings(obj: object, fn) -> None:
     """Apply ``fn`` to every string VALUE reachable in ``obj``, in place.
 
-    Values only, never dict keys: no extractor bucket is keyed by a node id or a
-    path (the ``*_type_table`` maps are ``name -> type``), and rewriting keys
-    could silently collide two entries into one.
+    Values only, never dict keys: rewriting keys blindly could silently
+    collide two entries into one. The single id-keyed bucket -
+    ``objc_field_types["tables"]`` - is handled by
+    :func:`_rewrite_id_keyed_table_keys` beside each call to this (#3150).
     """
     if isinstance(obj, dict):
         items: "Iterable" = obj.items()
@@ -845,6 +863,7 @@ def _relativize_ids_in(payload: dict, path: "str | Path", root: Path) -> None:
         return value
 
     _rewrite_strings(payload, anchor)
+    _rewrite_id_keyed_table_keys(payload, anchor)
 
 
 def _absolutize_ids_in(payload: dict, path: "str | Path", root: Path) -> None:
@@ -873,6 +892,7 @@ def _absolutize_ids_in(payload: dict, path: "str | Path", root: Path) -> None:
         return value
 
     _rewrite_strings(payload, restore)
+    _rewrite_id_keyed_table_keys(payload, restore)
 
 
 def _absolutize_source_files_in(payload: dict, root: Path) -> None:

graphify/extract.py

@@ -2487,6 +2487,26 @@ def _augment_js_reexport_edges(
 # Header / implementation file-extension pairing for the decl/def class merge.
 
 
+def _remap_objc_field_tables(per_file: list, mapping: dict) -> None:
+    """Rewrite objc_field_types["tables"] KEYS through an id remap (#3150).
+
+    The #2591 field->type tables are the one extractor bucket keyed BY class
+    node id. The #1529 passes rewrote node ids, edge endpoints,
+    raw_calls[].caller_nid and swift_extensions[].nid but not these keys, so
+    whenever a common absolute prefix was stripped (always via
+    `graphify update <dir>`) the table keys went stale, every
+    field_types_by_class.get(cls) missed, and [self.<field> ...] sends
+    resolved to nothing - #2591 was inert through the CLI.
+    """
+    for result in per_file:
+        ft = result.get("objc_field_types") if isinstance(result, dict) else None
+        tables = ft.get("tables") if isinstance(ft, dict) else None
+        if not isinstance(tables, dict):
+            continue
+        if any(k in mapping for k in tables):
+            ft["tables"] = {mapping.get(k, k): v for k, v in tables.items()}
+
+
 def _merge_swift_extensions(
     per_file: list[dict],
     all_nodes: list[dict],
@@ -6209,6 +6229,9 @@ def extract(
                 en = ext.get("nid")
                 if en in id_remap:
                     ext["nid"] = id_remap[en]
+        # objc_field_types["tables"] is keyed BY class node id - the one bucket
+        # the #1529 rewrites missed (#3150).
+        _remap_objc_field_tables(per_file, id_remap)
     if prefix_remap:
         sym_remap: dict[str, str] = {}
         edge_alias_candidates: dict[str, set[str]] = {}
@@ -6276,6 +6299,7 @@ def extract(
                     en = ext.get("nid")
                     if en in sym_remap:
                         ext["nid"] = sym_remap[en]
+            _remap_objc_field_tables(per_file, sym_remap)
         if edge_alias_candidates:
             def _edge_key(edge: dict) -> str:
                 # target_file is a transient stamp (#1814/#1983); exclude it

tests/test_objc_field_table_remap.py

@@ -0,0 +1,134 @@
+"""The ObjC field->type table must survive the id remaps (#3150).
+
+`_resolve_objc_member_calls`' table (#2591) is the one extractor bucket keyed
+BY class node id. The #1529 passes rewrote node ids, edge endpoints,
+`raw_calls[].caller_nid` and `swift_extensions[].nid` — but not those keys.
+The remap fires whenever the input paths carry a common absolute prefix,
+i.e. always via `graphify update <dir>`, so `[self.<field> …]` receiver
+typing was inert through the CLI and worked only in tests, which hand
+extract() already-relative paths. The cached shard had the same split: the
+portability rewrite re-anchored every id except the table keys.
+"""
+from __future__ import annotations
+
+import io
+from contextlib import redirect_stdout
+from pathlib import Path
+
+import pytest
+
+from graphify.extract import extract
+
+try:
+    import tree_sitter_objc  # noqa: F401
+    HAVE_OBJC = True
+except ImportError:
+    HAVE_OBJC = False
+
+FILES = {
+    "src/Greeter.h": (
+        "#import <Foundation/Foundation.h>\n"
+        "@interface Greeter : NSObject\n- (void)greet;\n@end\n"),
+    "src/Greeter.m": (
+        '#import "Greeter.h"\n@implementation Greeter\n'
+        '- (void)greet { NSLog(@"hi"); }\n@end\n'),
+    "src/Direct.h": (
+        "#import <Foundation/Foundation.h>\n#import \"Greeter.h\"\n"
+        "@interface Direct : NSObject\n"
+        "@property (nonatomic, strong) Greeter *greeter;\n- (void)run;\n@end\n"),
+    "src/Direct.m": (
+        '#import "Direct.h"\n@implementation Direct\n'
+        "- (void)run { [self.greeter greet]; }\n@end\n"),
+}
+
+
+def _write(tmp_path):
+    for name, body in FILES.items():
+        p = tmp_path / name
+        p.parent.mkdir(parents=True, exist_ok=True)
+        p.write_text(body, encoding="utf-8")
+    return tmp_path
+
+
+def _calls(result):
+    labels = {n["id"]: n["label"] for n in result["nodes"]}
+    return {(labels.get(e["source"]), labels.get(e["target"]))
+            for e in result["edges"] if e.get("relation") == "calls"}
+
+
+needs_objc = pytest.mark.skipif(not HAVE_OBJC, reason="tree-sitter-objc not installed")
+
+
+@needs_objc
+def test_receiver_typing_survives_absolute_input_paths(tmp_path):
+    """The CLI shape: absolute inputs, common prefix stripped by the #1529
+    remap. This is the run where #2591 emitted zero edges."""
+    corpus = _write(tmp_path)
+    cache = tmp_path / "out"
+    with redirect_stdout(io.StringIO()):
+        r = extract([(corpus / n).resolve() for n in FILES], cache_root=cache, parallel=False)
+    assert ("-run", "-greet") in _calls(r), sorted(_calls(r))
+
+
+@needs_objc
+def test_receiver_typing_still_works_with_relative_paths(tmp_path, monkeypatch):
+    """The shape the original #2591 tests used — must keep working."""
+    corpus = _write(tmp_path)
+    monkeypatch.chdir(corpus)
+    cache = tmp_path / "out"
+    with redirect_stdout(io.StringIO()):
+        r = extract([Path(n) for n in FILES], cache_root=cache, parallel=False)
+    assert ("-run", "-greet") in _calls(r)
+
+
+@needs_objc
+def test_a_cached_shard_replays_with_consistent_table_keys(tmp_path):
+    """Warm-cache CLI run: the shard is written on the first pass and replayed
+    on the second; the table keys must still match the node ids."""
+    corpus = _write(tmp_path)
+    cache = tmp_path / "out"
+    paths = [(corpus / n).resolve() for n in FILES]
+    with redirect_stdout(io.StringIO()):
+        extract(paths, cache_root=cache, parallel=False)          # cold: writes shards
+        r = extract(paths, cache_root=cache, parallel=False)      # warm: replays them
+    assert ("-run", "-greet") in _calls(r), sorted(_calls(r))
+
+
+def test_the_in_process_remap_rewrites_the_table_keys():
+    """Unit form of the CLI-path fix: the same mapping that rewrites node ids
+    must rewrite the table keys."""
+    try:
+        from graphify.extract import _remap_objc_field_tables
+    except ImportError:  # pre-fix tree
+        pytest.skip("pre-fix tree")
+    per_file = [{"objc_field_types": {"path": "src/Direct.h",
+                                      "tables": {"abs_slug_direct": {"greeter": "Greeter"}}}},
+                {"nodes": []}]
+    _remap_objc_field_tables(per_file, {"abs_slug_direct": "src_direct_direct"})
+    assert per_file[0]["objc_field_types"]["tables"] == {"src_direct_direct": {"greeter": "Greeter"}}
+
+
+def test_cache_portability_rewrites_the_table_keys(tmp_path):
+    """Round-trip a payload through the #2257 portability rewrite: the class id
+    inside the table key must follow the node id."""
+    from graphify.cache import _absolutize_ids_in, _relativize_ids_in
+    from graphify.extractors.base import _make_id
+
+    root = tmp_path / "proj"
+    root.mkdir()
+    f = root / "Direct.m"
+    f.write_text("@implementation Direct\n@end\n", encoding="utf-8")
+    abs_id = _make_id(str(root)) + "_direct_direct"
+    assert _relativize_ids_in is not None
+    payload = {
+        "nodes": [{"id": abs_id, "label": "Direct"}],
+        "edges": [],
+        "objc_field_types": {"path": str(f), "tables": {abs_id: {"greeter": "Greeter"}}},
+    }
+    _relativize_ids_in(payload, f, root)
+    stored_key = next(iter(payload["objc_field_types"]["tables"]))
+    assert stored_key == payload["nodes"][0]["id"], "key and id diverged on store"
+    _absolutize_ids_in(payload, f, root)
+    restored_key = next(iter(payload["objc_field_types"]["tables"]))
+    assert restored_key == payload["nodes"][0]["id"], "key and id diverged on load"
+    assert payload["objc_field_types"]["tables"][restored_key] == {"greeter": "Greeter"}