Merge pull request DeusData#1940 from ilyabrykau-orca/fix/go-struct-fields

fix(extract): descend into Go struct field_declaration_list

Author: DeusData

internal/cbm/extract_defs.c

@@ -4780,6 +4780,20 @@ static TSNode find_class_member_body(TSNode class_node, CBMLanguage lang) {
     return ts_node_is_null(declarations) ? body : declarations;
 }
 
+/* Go structs keep their field_declaration nodes one level below the body that
+ * find_class_body() returns: type_spec's `type` child is a struct_type whose
+ * only named child is a field_declaration_list. Interfaces need no such step --
+ * interface_type holds its method specs directly, which is why interface members
+ * extracted correctly while every struct field was silently skipped. Normalize
+ * here, the same way the Java enum_body_declarations step above does. */
+static TSNode go_normalize_struct_body(TSNode body) {
+    if (ts_node_is_null(body) || strcmp(ts_node_type(body), "struct_type") != 0) {
+        return body;
+    }
+    TSNode list = cbm_find_child_by_kind(body, "field_declaration_list");
+    return ts_node_is_null(list) ? body : list;
+}
+
 // Dart: resolve method name from method_signature/function_signature.
 static TSNode resolve_dart_method_name(TSNode child, const char *ck) {
     if (strcmp(ck, "method_signature") == 0) {
@@ -6656,6 +6670,9 @@ static void extract_class_fields(CBMExtractCtx *ctx, TSNode class_node, const ch
     }
 
     TSNode body = find_class_member_body(class_node, ctx->language);
+    if (ctx->language == CBM_LANG_GO) {
+        body = go_normalize_struct_body(body);
+    }
     if (ts_node_is_null(body)) {
         return;
     }
@@ -6945,6 +6962,13 @@ static void extract_class_fields(CBMExtractCtx *ctx, TSNode class_node, const ch
             continue;
         }
 
+        /* Go: `_` is the blank identifier, used for explicit struct padding in
+         * generated code. It is not a referenceable field, and emitting it gives
+         * every `_` in the repository a same-named node to collide with. */
+        if (ctx->language == CBM_LANG_GO && strcmp(name, "_") == 0) {
+            continue;
+        }
+
         const char *field_qn = cbm_arena_sprintf(a, "%s.%s", class_qn, name);
 
         CBMDefinition def;

tests/test_extraction.c

@@ -3015,6 +3015,59 @@ TEST(go_imports) {
     PASS();
 }
 
+/* #1935: Go struct fields were never extracted — find_class_body() returns the
+ * struct_type node, whose only named child is a field_declaration_list, so the
+ * member loop matched nothing and every field was silently skipped (0 Field
+ * nodes for ~5055 declarations on the measured repo). Interfaces hold their
+ * method specs directly and always worked. The blank identifier `_` is struct
+ * padding, not a referenceable field, and must stay out (241 collision edges
+ * on two generated structs otherwise). */
+TEST(extract_go_struct_fields_have_nodes) {
+    CBMFileResult *r = extract("package fxf\n\n"
+                               "type Config struct {\n"
+                               "\tName    string\n"
+                               "\tTimeout int\n"
+                               "\tNested  *Config\n"
+                               "\t_       [8]byte\n"
+                               "}\n\n"
+                               "type Reader interface {\n"
+                               "\tRead(p []byte) (int, error)\n"
+                               "\tClose() error\n"
+                               "}\n",
+                               CBM_LANG_GO, "t", "cfg.go");
+    ASSERT_NOT_NULL(r);
+    ASSERT_FALSE(r->has_error);
+    /* RED before the descend fix: count is 0. The blank identifier must not
+     * bring it to 4. */
+    ASSERT_EQ(count_defs_with_label(r, "Field"), 3);
+    ASSERT_TRUE(has_def(r, "Field", "Name"));
+    ASSERT_TRUE(has_def(r, "Field", "Timeout"));
+    ASSERT_TRUE(has_def(r, "Field", "Nested"));
+    ASSERT_FALSE(has_def(r, "Field", "_"));
+    /* Each field carries its declared type in return_type. */
+    for (int i = 0; i < r->defs.count; i++) {
+        const CBMDefinition *d = &r->defs.items[i];
+        if (!d->label || strcmp(d->label, "Field") != 0) {
+            continue;
+        }
+        ASSERT_NOT_NULL(d->return_type);
+        if (strcmp(d->name, "Name") == 0) {
+            ASSERT_TRUE(strcmp(d->return_type, "string") == 0);
+        }
+        if (strcmp(d->name, "Timeout") == 0) {
+            ASSERT_TRUE(strcmp(d->return_type, "int") == 0);
+        }
+        if (strcmp(d->name, "Nested") == 0) {
+            ASSERT_TRUE(strcmp(d->return_type, "*Config") == 0);
+        }
+    }
+    /* Interface members keep extracting exactly as before. */
+    ASSERT_TRUE(has_def(r, "Method", "Read"));
+    ASSERT_TRUE(has_def(r, "Method", "Close"));
+    cbm_free_result(r);
+    PASS();
+}
+
 TEST(java_imports) {
     CBMFileResult *r = extract(
         "import java.util.List;\nimport java.util.ArrayList;\nimport static java.lang.Math.PI;\n"
@@ -6699,6 +6752,7 @@ SUITE(extraction) {
     RUN_TEST(python_imports);
     RUN_TEST(js_imports);
     RUN_TEST(go_imports);
+    RUN_TEST(extract_go_struct_fields_have_nodes);
     RUN_TEST(java_imports);
     RUN_TEST(rust_imports);
     RUN_TEST(c_imports);