fix(extract): give each Go init() its own QN

internal/cbm/extract_calls.c

@@ -3619,6 +3619,24 @@ CBMInvocationDescriptor handle_calls(CBMExtractCtx *ctx, TSNode node, const CBML
                     }
                 }
             }
+            // Go receiver-aware guard (same direction as the TS/JS flag above).
+            // Flag a selector call x.foo(). The Go AST cannot separate a method
+            // call on a value from a package-qualified call — but every selector
+            // call the Go LSP or the import/qualified registry strategies CAN
+            // place never reaches the weak short-name guards, so the flag only
+            // bites on unresolvable receivers (`f.Close()` on an os.File,
+            // `sha256.New()` behind an unindexed import), where a project-wide
+            // short-name match fabricates an edge to an unrelated project
+            // symbol sharing the name. Bare calls (helper()) keep
+            // is_method=false and resolve same-module/import paths as before.
+            if (ctx->language == CBM_LANG_GO &&
+                strcmp(ts_node_type(node), "call_expression") == 0) {
+                TSNode gofn = ts_node_child_by_field_name(node, TS_FIELD("function"));
+                if (!ts_node_is_null(gofn) &&
+                    strcmp(ts_node_type(gofn), "selector_expression") == 0) {
+                    call.is_method = true;
+                }
+            }
 
             TSNode args = ts_node_child_by_field_name(node, TS_FIELD("arguments"));
             // ObjectScript stores args under oref_method/method_args, not the

internal/cbm/extract_defs.c

@@ -3508,7 +3508,7 @@ static void set_def_complexity(CBMDefinition *def, TSNode body, const CBMLangSpe
  * Walks to the parameter_declaration's `type` field, unwrapping pointer_type
  * and generic_type, and returns the type_identifier text (e.g. "OrderService").
  * Returns NULL if no type_identifier is found. */
-static char *go_receiver_type_name(CBMArena *a, TSNode recv, const char *source) {
+char *cbm_go_receiver_type_name(CBMArena *a, TSNode recv, const char *source) {
     uint32_t nc = ts_node_child_count(recv);
     for (uint32_t i = 0; i < nc; i++) {
         TSNode child = ts_node_child(recv, i);
@@ -3720,13 +3720,42 @@ static void extract_func_def(CBMExtractCtx *ctx, TSNode node, const CBMLangSpec
          * (and downstream Go IMPLEMENTS/OVERRIDE) link the method to its owning
          * struct/type node.  The parent QN must match the type's node QN, which
          * is computed the same way (cbm_fqn_compute on the type name). */
-        char *recv_type = go_receiver_type_name(a, recv, ctx->source);
+        char *recv_type = cbm_go_receiver_type_name(a, recv, ctx->source);
         if (recv_type && recv_type[0]) {
             /* Must match the Go type node QN (directory-based module) so the
              * DEFINES_METHOD edge links the method to its owning type. */
             def.parent_class = cbm_fqn_compute_source_lang(a, ctx->project, ctx->rel_path,
                                                            recv_type, ctx->language);
-        }
+            /* Receiver-qualify the method QN (proj.pkg.Recv.method) — same
+             * shape as the C++ out-of-line path below and Go interface
+             * members. With the flat proj.pkg.method QN every same-name
+             * method in a package collided in the graph upsert: one body
+             * survived and the twins' call edges accreted onto it. The
+             * call-scope side (compute_func_qn in extract_unified.c) mirrors
+             * this formula, and go_lsp consumers read the def QN and
+             * parent_class (receiver_type) verbatim, so resolution joins
+             * stay exact. */
+            def.qualified_name = cbm_arena_sprintf(a, "%s.%s", def.parent_class, name);
+        }
+    }
+
+    /* Go allows any number of init() functions per package — even several in
+     * one file — and they all run at start-up. On the flat QN they all
+     * collided and the graph upsert kept ONE node per package, silently
+     * dropping the rest (#1910). Disambiguate with the #495 cfg-twin pattern:
+     * fold the file basename and the init's per-file ordinal into the QN.
+     * The ordinal (not the line) keeps the QN stable when code is edited
+     * above the function — the QN is node identity, and a line suffix would
+     * churn nodes on every unrelated insertion. Nothing ever joins on the
+     * plain QN — calling init explicitly is illegal in Go — and the
+     * call-scope side (compute_func_qn in extract_unified.c) computes the
+     * same cbm_go_init_ordinal so init-body calls keep their attribution. */
+    if (ctx->language == CBM_LANG_GO && strcmp(def.label, "Function") == 0 &&
+        strcmp(name, "init") == 0) {
+        const char *base = strrchr(ctx->rel_path, '/');
+        base = base ? base + 1 : ctx->rel_path;
+        def.qualified_name = cbm_arena_sprintf(a, "%s#%s:%d", def.qualified_name, base,
+                                               cbm_go_init_ordinal(node, ctx->source));
     }
 
     // C++/CUDA: out-of-line method definition (`Foo::bar` in a .cc/.cpp). The

internal/cbm/extract_unified.c

@@ -899,6 +899,41 @@ static const char *compute_func_qn(CBMExtractCtx *ctx, TSNode node, const CBMLan
         }
     }
 
+    /* Go method `func (s *Storage) Close() {...}`: the def extractor records
+     * this as Method "proj.pkg.Storage.Close" (receiver-qualified, mirroring
+     * the C++ out-of-line rule above). The call-scope QN must match — a bare
+     * "proj.pkg.Close" names a node that no longer exists, so every call
+     * inside the method body would fall back to File-node attribution
+     * (calls_find_source). Same ONE-formula contract as the def side:
+     * cbm_go_receiver_type_name + cbm_fqn_compute_source_lang. */
+    if (ctx->language == CBM_LANG_GO && strcmp(ts_node_type(node), "method_declaration") == 0) {
+        TSNode recv = ts_node_child_by_field_name(node, TS_FIELD("receiver"));
+        if (!ts_node_is_null(recv)) {
+            char *recv_type = cbm_go_receiver_type_name(ctx->arena, recv, ctx->source);
+            if (recv_type && recv_type[0]) {
+                const char *type_qn = cbm_fqn_compute_source_lang(
+                    ctx->arena, ctx->project, ctx->rel_path, recv_type, ctx->language);
+                return cbm_arena_sprintf(ctx->arena, "%s.%s", type_qn, name);
+            }
+        }
+    }
+
+    /* Go init(): the def extractor folds the file basename and the init's
+     * per-file ordinal into the QN so every init in a package survives the
+     * upsert (#1910, the #495 cfg-twin pattern; ordinal, not line, so the QN
+     * is stable under edits above the function). Mirror the exact formula
+     * here, or init-body calls fall back to File-node attribution
+     * (calls_find_source). */
+    if (ctx->language == CBM_LANG_GO && strcmp(name, "init") == 0 &&
+        strcmp(ts_node_type(node), "function_declaration") == 0) {
+        const char *base_qn = cbm_fqn_compute_source_lang(ctx->arena, ctx->project, ctx->rel_path,
+                                                          name, ctx->language);
+        const char *base = strrchr(ctx->rel_path, '/');
+        base = base ? base + 1 : ctx->rel_path;
+        return cbm_arena_sprintf(ctx->arena, "%s#%s:%d", base_qn, base,
+                                 cbm_go_init_ordinal(node, ctx->source));
+    }
+
     /* Nix: a binding's own attrpath contributes scope (`a.b.fn = …`), and the def
      * extractor bakes it into the def QN. Compose it identically here — otherwise
      * an in-body call sources to a QN one or more segments short of the def, and

internal/cbm/helpers.c

@@ -1734,6 +1734,42 @@ int cbm_classify_string(const char *str, int len) {
  * canonical parameter shape of server-side route paths
  * (`/things/${id}/x` -> "/things/{}/x"). Returns NULL when the node yields
  * no text or exceeds the route-sized buffer. */
+/* 1-based source-order ordinal of a top-level Go `init` function_declaration
+ * among the file's `init`s. Both the definition extractor and compute_func_qn
+ * fold it into the QN (`pkg.init#file.go:N`, #1910), so it must be computed
+ * from the tree on both sides with this one formula. Unlike a line number,
+ * the ordinal is stable under edits above the function — QNs are node
+ * identity, and a line-based suffix would churn nodes on every unrelated
+ * insertion (the #495 cfg suffix and the GoogleTest derivation are both
+ * edit-stable for the same reason). */
+int cbm_go_init_ordinal(TSNode fn_node, const char *source) {
+    TSNode root = fn_node;
+    for (TSNode p = ts_node_parent(root); !ts_node_is_null(p); p = ts_node_parent(p)) {
+        root = p;
+    }
+    int ordinal = 0;
+    uint32_t n = ts_node_named_child_count(root);
+    for (uint32_t i = 0; i < n; i++) {
+        TSNode child = ts_node_named_child(root, i);
+        if (strcmp(ts_node_type(child), "function_declaration") != 0) {
+            continue;
+        }
+        TSNode name = ts_node_child_by_field_name(child, TS_FIELD("name"));
+        if (ts_node_is_null(name)) {
+            continue;
+        }
+        uint32_t start = ts_node_start_byte(name);
+        if (ts_node_end_byte(name) - start != 4 || memcmp(source + start, "init", 4) != 0) {
+            continue;
+        }
+        ordinal++;
+        if (ts_node_eq(child, fn_node)) {
+            return ordinal;
+        }
+    }
+    return ordinal;
+}
+
 const char *cbm_template_string_text(CBMArena *a, TSNode node, const char *source) {
     enum { TPL_BUF = 512 };
     char buf[TPL_BUF];

internal/cbm/helpers.h

@@ -119,6 +119,12 @@ TSNode cbm_resolve_func_name(TSNode node, CBMLanguage lang);
 // def extractor — drift dropped the class qualifier from in-body calls (#554/#621).
 char *cbm_cpp_out_of_line_parent_class(CBMArena *a, TSNode node, const char *source);
 
+/* Go: resolve a method_declaration's receiver parameter_list down to the bare
+ * receiver type_identifier (unwrapping pointer_type / generic_type). Shared by
+ * def extraction (extract_defs.c) and call-scope attribution
+ * (extract_unified.c) so the receiver-qualified method QN has ONE formula. */
+char *cbm_go_receiver_type_name(CBMArena *a, TSNode recv, const char *source);
+
 // Find a child node by kind string.
 TSNode cbm_find_child_by_kind(TSNode parent, const char *kind);
 
@@ -191,6 +197,10 @@ bool cbm_is_loop_node_type(const char *kind);
 // Is this a module-level node? (not nested inside function/class body)
 bool cbm_is_module_level(TSNode node, CBMLanguage lang);
 
+/* 1-based source-order ordinal of a Go `init` among its file's top-level
+ * `init` function_declarations (QN disambiguation, #1910). */
+int cbm_go_init_ordinal(TSNode fn_node, const char *source);
+
 // Same check, but the node's PARENT is supplied directly — avoids the
 // O(n) ts_node_parent rescan. Use at call sites iterating a known
 // parent's children (the common case). `parent` is the parent of the

internal/cbm/lsp/go_lsp.c

@@ -1859,15 +1859,24 @@ static void process_function(GoLSPContext* ctx, TSNode func_node) {
     char* func_name = lsp_node_text(ctx, name_node);
     if (!func_name || !func_name[0]) return;
 
-    // Enclosing-function QN must be the BARE package.Func form (no receiver
-    // type segment). The textual call events (extract_unified.c) source calls
-    // as package_qn.func_name — methods included — and the defs pass creates
-    // the graph Method node under the same QN, so any other form breaks the
-    // caller-QN join in cbm_pipeline_find_lsp_resolution and the LSP-resolved
-    // call silently falls back to the registry short-name resolver. The
-    // receiver type still reaches the registry via the def's parent_class /
-    // method->receiver_type; it just does not appear in the caller QN.
+    // Enclosing-function QN must be EXACTLY the QN the textual call events
+    // (extract_unified.c compute_func_qn) and the defs pass produce, or the
+    // caller-QN join in cbm_pipeline_find_lsp_resolution breaks and the
+    // LSP-resolved call silently falls back to the registry short-name
+    // resolver. Since #1909 receiver-qualified Go method QNs, that shared
+    // form is package_qn.ReceiverType.method for methods (the ONE-formula
+    // contract: cbm_go_receiver_type_name) and package_qn.func for functions.
     ctx->enclosing_func_qn = cbm_arena_sprintf(ctx->arena, "%s.%s", ctx->package_qn, func_name);
+    if (strcmp(ts_node_type(func_node), "method_declaration") == 0) {
+        TSNode recv = ts_node_child_by_field_name(func_node, "receiver", 8);
+        if (!ts_node_is_null(recv)) {
+            char *recv_type = cbm_go_receiver_type_name(ctx->arena, recv, ctx->source);
+            if (recv_type && recv_type[0]) {
+                ctx->enclosing_func_qn = cbm_arena_sprintf(ctx->arena, "%s.%s.%s", ctx->package_qn,
+                                                           recv_type, func_name);
+            }
+        }
+    }
 
     // Push function scope
     CBMScope* saved_scope = ctx->current_scope;

src/pipeline/pass_calls.c

@@ -623,12 +623,20 @@ static int resolve_single_call(cbm_pipeline_ctx_t *ctx, CBMCall *call,
      * language gated on only one resolver produces an edge on the sequential
      * path and not the parallel one (or vice versa), breaking MT determinism.
      * ArkTS belongs to the JS/TS family here (#1842); dropping it would
-     * reintroduce the #592/#606 false-edge class for .ets files. */
+     * reintroduce the #592/#606 false-edge class for .ets files.
+     *
+     * Go (#1906) rides the same deferred-drop plumbing through its OWN
+     * predicate: its drop-list differs (field_type_hint is receiver-aware for
+     * Go, and unique_name drops only when import-unreachability-penalized), so
+     * it composes via cbm_go_suppress_weak_method_match instead of widening
+     * the shared gate. Same lockstep rule: mirror pass_parallel.c. */
     bool suppress_weak_member = lang == CBM_LANG_PYTHON || lang == CBM_LANG_JAVASCRIPT ||
                                 lang == CBM_LANG_TYPESCRIPT || lang == CBM_LANG_TSX ||
                                 lang == CBM_LANG_ARKTS;
     bool drop_plain_call =
-        cbm_suppress_weak_member_match(suppress_weak_member, call->is_method, res.strategy);
+        cbm_suppress_weak_member_match(suppress_weak_member, call->is_method, res.strategy) ||
+        cbm_go_suppress_weak_method_match(lang == CBM_LANG_GO, call->is_method, res.strategy,
+                                          res.confidence);
 
     /* Service-pattern HTTP/ASYNC calls to an EXTERNAL client library (e.g.
      * `requests.get("/api/orders/{id}")`) resolve to a QN containing the library

src/pipeline/pass_parallel.c

@@ -2488,12 +2488,16 @@ static void resolve_file_calls(resolve_ctx_t *rc, resolve_worker_state_t *ws, CB
          * #606 direction.
          *
          * This language set MUST match the one in pass_calls.c exactly — see the
-         * note there. ArkTS belongs to the JS/TS family (#1842). */
+         * note there. ArkTS belongs to the JS/TS family (#1842). Go (#1906)
+         * composes via its own predicate (different drop-list — see
+         * cbm_go_suppress_weak_method_match), mirrored in pass_calls.c. */
         bool suppress_weak_member = lang == CBM_LANG_PYTHON || lang == CBM_LANG_JAVASCRIPT ||
                                     lang == CBM_LANG_TYPESCRIPT || lang == CBM_LANG_TSX ||
                                     lang == CBM_LANG_ARKTS;
         bool drop_plain_call =
-            cbm_suppress_weak_member_match(suppress_weak_member, call->is_method, res.strategy);
+            cbm_suppress_weak_member_match(suppress_weak_member, call->is_method, res.strategy) ||
+            cbm_go_suppress_weak_method_match(lang == CBM_LANG_GO, call->is_method, res.strategy,
+                                              res.confidence);
 
         /* Service-pattern HTTP/ASYNC client call (`requests.get(url)`): the
          * service signal lives in the callee_name. The registry can mis-resolve

src/pipeline/pipeline.h

@@ -280,6 +280,15 @@ bool cbm_perl_suppress_generic_match(bool is_perl, bool is_method, const char *c
  * Pure; unit-tested in test_registry.c. */
 bool cbm_suppress_weak_member_match(bool enabled, bool is_method, const char *strategy);
 
+/* Go analog of the TS/JS guard, same failure class: a selector call whose
+ * receiver the Go LSP could not type must not be bound by a receiver-blind
+ * short-name strategy. Drops suffix_match / fuzzy always, and unique_name only
+ * when its confidence is import-unreachability-penalized (the stdlib/vendor
+ * hijack shape). field_type_hint is deliberately NOT dropped for Go — struct
+ * fields carry declared types, so the hint is receiver-aware there. */
+bool cbm_go_suppress_weak_method_match(bool is_go, bool is_method, const char *strategy,
+                                       double confidence);
+
 /* #725: drop a suffix_match CALLS edge when the caller language and the
  * target file's language disagree. unique_name (candidates == 1) is #1572
  * and is left alone; same_module / import_map / lsp_* are kept. JS/TS/TSX

src/pipeline/registry.c

@@ -464,6 +464,33 @@ bool cbm_suppress_weak_member_match(bool enabled, bool is_method, const char *st
            strcmp(strategy, "field_type_hint") == 0 || strcmp(strategy, "fuzzy") == 0;
 }
 
+bool cbm_go_suppress_weak_method_match(bool is_go, bool is_method, const char *strategy,
+                                       double confidence) {
+    if (!is_go || !is_method || !strategy || !strategy[0]) {
+        return false;
+    }
+    /* Go analog of the TS/JS guard above, same failure class: a selector call
+     * whose receiver the Go LSP could not type reaches the registry and a bare
+     * short-name strategy binds it to an arbitrary same-named project symbol
+     * (`f.Close()` on an os.File -> a project `Close`, suffix_match over 15
+     * candidates). Unlike the TS/JS list, field_type_hint is KEPT: a Go struct
+     * field carries a declared type, so the parallel resolver's field-type
+     * hint is receiver-aware for Go (lrp_go_s8_field_type_hint), not a
+     * heuristic. */
+    if (strcmp(strategy, "suffix_match") == 0 || strcmp(strategy, "fuzzy") == 0) {
+        return true;
+    }
+    /* unique_name is dropped only when PENALIZED: resolve_name_lookup scales
+     * CONF_UNIQUE_NAME by DEFAULT_CONFIDENCE exactly when the lone candidate
+     * is not reachable through the caller's imports — the stdlib/vendor
+     * hijack shape (`io.Copy` -> a project `Copy`). An unpenalized
+     * unique_name target sits inside the caller's import closure (or the
+     * file has no imports, e.g. a same-package call) and must be kept —
+     * dropping it kills genuinely-typed lone-candidate calls that never
+     * enter the field-type-hint upgrade (candidate_count == 1). */
+    return strcmp(strategy, "unique_name") == 0 && confidence < CONF_UNIQUE_NAME;
+}
+
 static bool js_ts_family(CBMLanguage lang) {
     return lang == CBM_LANG_JAVASCRIPT || lang == CBM_LANG_TYPESCRIPT || lang == CBM_LANG_TSX ||
            lang == CBM_LANG_ARKTS;