fix(registry): reach a cfg-fenced function from its bare name

src/pipeline/registry.c

@@ -858,9 +858,38 @@ void cbm_registry_free(cbm_registry_t *r) {
 
 /* ── Registration ────────────────────────────────────────────────── */
 
+/* Record `owned_qn` in the by-name bucket for `key`, keeping the bucket's
+ * is_test flags in step with its entries.
+ *
+ * No array dedup needed: cbm_registry_add's exact-map check guarantees the QN
+ * is new, and it calls this at most once per distinct key. */
+static void index_under_name(cbm_registry_t *r, const char *key, const char *owned_qn) {
+    qn_array_t *arr = cbm_ht_get(r->by_name, key);
+    if (!arr) {
+        arr = calloc(CBM_ALLOC_ONE, sizeof(qn_array_t));
+        cbm_ht_set(r->by_name, strdup(key), arr);
+    }
+    int before = arr->count;
+    cbm_da_push(arr, (char *)owned_qn);
+    if (arr->count == before) {
+        return; /* the name could not be recorded: no verdict to cache */
+    }
+    if (arr->count > arr->is_test_cap) {
+        int want = arr->cap > 0 ? arr->cap : arr->count;
+        uint8_t *grown =
+            cbm_realloc(CBM_MEM_CLASS_DYN_ARRAY, arr->is_test, (size_t)want * sizeof(uint8_t));
+        if (grown) {
+            arr->is_test = grown;
+            arr->is_test_cap = want;
+        }
+    }
+    if (arr->count <= arr->is_test_cap) {
+        arr->is_test[arr->count - SKIP_ONE] = is_test_qn(owned_qn) ? 1 : 0;
+    }
+}
+
 void cbm_registry_add(cbm_registry_t *r, const char *name, const char *qualified_name,
                       const char *label) {
-    (void)name;
     if (!r || !qualified_name || !label) {
         return;
     }
@@ -893,30 +922,37 @@ void cbm_registry_add(cbm_registry_t *r, const char *name, const char *qualified
     cbm_ht_set(r->exact, strdup(qualified_name), (void *)interned);
     const char *owned_qn = cbm_ht_get_key(r->exact, qualified_name);
 
-    /* Index by simple name.
-     * No array dedup needed: exact-map check above guarantees uniqueness. */
-    const char *simple = simple_name(qualified_name);
-    qn_array_t *arr = cbm_ht_get(r->by_name, simple);
-    if (!arr) {
-        arr = calloc(CBM_ALLOC_ONE, sizeof(qn_array_t));
-        cbm_ht_set(r->by_name, strdup(simple), arr);
-    }
-    int before = arr->count;
-    cbm_da_push(arr, (char *)owned_qn);
-    if (arr->count == before) {
-        return; /* the name could not be recorded: no verdict to cache */
-    }
-    if (arr->count > arr->is_test_cap) {
-        int want = arr->cap > 0 ? arr->cap : arr->count;
-        uint8_t *grown =
-            cbm_realloc(CBM_MEM_CLASS_DYN_ARRAY, arr->is_test, (size_t)want * sizeof(uint8_t));
-        if (grown) {
-            arr->is_test = grown;
-            arr->is_test_cap = want;
-        }
-    }
-    if (arr->count <= arr->is_test_cap) {
-        arr->is_test[arr->count - SKIP_ONE] = is_test_qn(owned_qn) ? 1 : 0;
+    /* Index the symbol under the QN's last dot segment, and additionally under
+     * the name its caller passed when that segment carries a '#' fence.
+     *
+     * The derived key is the one every language has always used and it stays
+     * unconditional, so a grammar whose QNs carry no '#' is byte-identical to
+     * before this commit. The second key exists for one shape: a fenced tail is
+     * a literal string no bare callee is ever written as. rust_cfg_qualified_name
+     * mints a `#[cfg(test)]` twin as "proj.lib.add#cfg(test)", simple_name() has
+     * no '#' handling, so the derived key filed that function under the whole
+     * string "add#cfg(test)" where no bare `add` callee could reach it.
+     *
+     * Gating on the fence rather than on the file's language is what makes
+     * "unchanged for every other grammar" checkable instead of asserted. Every
+     * by-name lookup keys through simple_name(), which splits on '.' and "::"
+     * only, so a passed name that differs from the derived key by anything
+     * OTHER than a fence is a key no lookup can reach: an HCL block's
+     * "resource.aws_instance.web" and a TOML table's "tool.poetry.dependencies"
+     * are both already indexed under the tail a reference spells, and adding
+     * their dotted form would only widen the bucket the scorer walks.
+     *
+     * `name` is NULL or empty only for callers that have no symbol name to
+     * give; those have the derived key and nothing else. */
+    const char *derived = simple_name(qualified_name);
+    index_under_name(r, derived, owned_qn);
+    /* '#' is a QN fence, and extract_defs.c's rust_cfg_qualified_name is the
+     * only thing in the tree that mints one today. A grammar that starts
+     * minting a '#' opts into this second key by doing so, whatever it means by
+     * the fence: its symbols become reachable under the passed name as well,
+     * and they share that name's bucket with everything else filed under it. */
+    if (name && name[0] && strchr(derived, '#') && strcmp(name, derived) != 0) {
+        index_under_name(r, name, owned_qn);
     }
 }
 

tests/test_pipeline.c

@@ -1147,6 +1147,60 @@ TEST(pipeline_nix_scoped_binding_calls_resolve) {
     PASS();
 }
 
+/* Terraform reference resolution, end to end.
+ *
+ * An HCL block names itself with its labels appended -- find_hcl_block_name
+ * mints "resource.aws_instance.web" -- while its QN's last dot segment is
+ * bare "web", and a reference written `aws_instance.web.id` reaches the
+ * by-name index through that tail. HCL is therefore a language where the
+ * definition name and the QN tail are different strings, and an index keyed on
+ * either one alone drops every cross-resource reference in the file.
+ *
+ * This has to be a pipeline test: the registry is shared by every language
+ * and nothing in the HCL extractor mentions the index key, so the two halves
+ * can disagree with every extraction-level assertion still green.
+ */
+TEST(pipeline_hcl_block_reference_resolves_to_its_block) {
+    if (setup_test_repo() != 0) {
+        FAIL("failed to create temp dir");
+    }
+
+    char tf_path[512];
+    snprintf(tf_path, sizeof(tf_path), "%s/main.tf", g_tmpdir);
+    FILE *tf = fopen(tf_path, "w");
+    if (!tf) {
+        teardown_test_repo();
+        FAIL("failed to write terraform fixture");
+    }
+    fprintf(tf, "resource \"aws_instance\" \"web\" {\n"
+                "  ami           = \"ami-0c55b159cbfafe1f0\"\n"
+                "  instance_type = \"t2.micro\"\n"
+                "}\n"
+                "\n"
+                "resource \"aws_eip\" \"ip\" {\n"
+                "  instance = aws_instance.web.id\n"
+                "}\n");
+    fclose(tf);
+
+    char tf_db[512];
+    snprintf(tf_db, sizeof(tf_db), "%s/test_hcl_refs.db", g_tmpdir);
+
+    cbm_pipeline_t *tp = cbm_pipeline_new(g_tmpdir, tf_db, CBM_MODE_FULL);
+    ASSERT_NOT_NULL(tp);
+    ASSERT_EQ(cbm_pipeline_run(tp), 0);
+
+    cbm_store_t *ts = cbm_store_open_path(tf_db);
+    ASSERT_NOT_NULL(ts);
+    const char *tf_project = cbm_pipeline_project_name(tp);
+
+    ASSERT(cross_file_edge_exists(ts, tf_project, "main", "resource.aws_instance.web", "USAGE"));
+
+    cbm_store_close(ts);
+    cbm_pipeline_free(tp);
+    teardown_test_repo();
+    PASS();
+}
+
 /* Regression: incremental re-index of an edited file must NOT drop inbound
  * cross-file CALLS edges whose source lives in an UNCHANGED file.
  *
@@ -15129,6 +15183,7 @@ SUITE(pipeline) {
     /* Calls pass */
     RUN_TEST(pipeline_calls_resolution);
     RUN_TEST(pipeline_nix_scoped_binding_calls_resolve);
+    RUN_TEST(pipeline_hcl_block_reference_resolves_to_its_block);
     RUN_TEST(pipeline_incremental_preserves_cross_file_calls);
     RUN_TEST(pipeline_objectscript_export_preserves_calls_sequential_parallel);
     RUN_TEST(pipeline_objectscript_export_incremental_matches_full_relationships);

tests/test_registry.c

@@ -325,6 +325,56 @@ TEST(resolve_qualified_ambiguous_tail_falls_through) {
     PASS();
 }
 
+/* cbm_registry_add used to discard its `name` argument and re-derive the
+ * lookup key from the QN's last dot segment. That made the QN's tail load
+ * bearing for the bare-name index every language shares: a Rust cfg twin,
+ * minted as "add#cfg(test)", was indexed under that literal string and no bare
+ * `add` callee could ever reach it. */
+TEST(registry_indexes_by_passed_name_not_qn_tail) {
+    cbm_registry_t *r = cbm_registry_new();
+    cbm_registry_add(r, "add", "proj.lib.add#cfg(test)", "Function");
+
+    cbm_resolution_t res = cbm_registry_resolve(r, "add", "proj.lib.caller", NULL, NULL, 0);
+    ASSERT_STR_EQ(res.qualified_name, "proj.lib.add#cfg(test)");
+
+    cbm_registry_free(r);
+    PASS();
+}
+
+/* The derived key stays unconditional, and this pins that.
+ *
+ * A name may carry segments the QN's tail drops, and then the tail is the key
+ * callers actually spell. An HCL block is named "resource.aws_instance.web" by
+ * find_hcl_block_name while its QN tail is bare "web", which is how an
+ * `aws_instance.web.id` reference reaches it. Re-keying the index on the passed
+ * name would lose that lookup outright, so the fence gate above leaves these
+ * shapes exactly as they were.
+ *
+ * The Module row registers a shape production cannot produce: every caller of
+ * cbm_registry_add gates on cbm_label_is_registry_symbol, which does not admit
+ * "Module". It is here because the registry's own contract is per-label-string,
+ * not per-caller, and a future label change should not silently drop the stem
+ * lookup a bare module reference needs. */
+TEST(registry_indexes_a_dotted_name_under_its_tail_too) {
+    cbm_registry_t *r = cbm_registry_new();
+    cbm_registry_add(r, "resource.aws_instance.web", "proj.main.resource.aws_instance.web",
+                     "Class");
+    cbm_registry_add(r, "helper.py", "proj.pkg.helper", "Module");
+
+    cbm_resolution_t tail = cbm_registry_resolve(r, "web", "proj.main", NULL, NULL, 0);
+    ASSERT_STR_EQ(tail.qualified_name, "proj.main.resource.aws_instance.web");
+
+    cbm_resolution_t whole =
+        cbm_registry_resolve(r, "resource.aws_instance.web", "proj.main", NULL, NULL, 0);
+    ASSERT_STR_EQ(whole.qualified_name, "proj.main.resource.aws_instance.web");
+
+    cbm_resolution_t stem = cbm_registry_resolve(r, "helper", "proj.pkg.caller", NULL, NULL, 0);
+    ASSERT_STR_EQ(stem.qualified_name, "proj.pkg.helper");
+
+    cbm_registry_free(r);
+    PASS();
+}
+
 TEST(resolve_import_map) {
     cbm_registry_t *r = cbm_registry_new();
     cbm_registry_add(r, "Process", "proj.pkg.worker.Process", "Function");
@@ -1201,6 +1251,8 @@ SUITE(registry) {
     RUN_TEST(resolve_same_module);
     RUN_TEST(resolve_qualified_disambiguates_same_name);
     RUN_TEST(resolve_qualified_ambiguous_tail_falls_through);
+    RUN_TEST(registry_indexes_by_passed_name_not_qn_tail);
+    RUN_TEST(registry_indexes_a_dotted_name_under_its_tail_too);
     RUN_TEST(resolve_import_map);
     RUN_TEST(resolve_import_map_bare_function);
     RUN_TEST(resolve_import_map_bare_alias);