feat: 枚举 enum (P1 #7)

- lexer: TOK_ENUM, TOK_COLON_COLON
- ast: AST_ENUM_DECL, AST_ENUM_VARIANT + AST_PROGRAM enums数组
- parser: enum Name { A, B } + Enum::Variant语法
- sema: SYM_ENUM, 变体验证, enum→i64类型兼容
- codegen: TYPE_ENUM→i64, 变体→ConstInt(索引值)
- 新增集成测试: 17_enum.l

测试: 121 通过 (41+15+47+18)

test/programs/17_enum.l

@@ -0,0 +1,6 @@
+enum Color { Red, Green, Blue }
+fn main() -> i64 {
+    let c = Color::Green;
+    print_i64(c);
+    return 0;
+}

test/test_codegen.c

@@ -13,7 +13,7 @@ void test_codegen_simple_function() {
     AstNode* body = ast_make_block(&a, stmts, 1, loc_at(1, 1));
     AstNode* fn = ast_make_function(&a, "main", NULL, 0, TYPE_I64, NULL, body, loc_at(1, 1));
     AstNode* fns[] = { fn };
-    AstNode* prog = ast_make_program(&a, fns, 1, NULL, 0, NULL, 0, loc_at(1, 1));
+    AstNode* prog = ast_make_program(&a, fns, 1, NULL, 0, NULL, 0, NULL, 0, loc_at(1, 1));
 
     const char* err = NULL;
     LLVMContextRef ctx = NULL;
@@ -47,7 +47,7 @@ void test_codegen_if_else() {
     AstNode* body = ast_make_block(&a, stmts, 1, loc_at(1, 1));
     AstNode* fn = ast_make_function(&a, "main", NULL, 0, TYPE_I64, NULL, body, loc_at(1, 1));
     AstNode* fns[] = { fn };
-    AstNode* prog = ast_make_program(&a, fns, 1, NULL, 0, NULL, 0, loc_at(1, 1));
+    AstNode* prog = ast_make_program(&a, fns, 1, NULL, 0, NULL, 0, NULL, 0, loc_at(1, 1));
 
     const char* err = NULL;
     LLVMContextRef ctx2 = NULL;
@@ -78,7 +78,7 @@ void test_codegen_binary_ops() {
     AstNode* body = ast_make_block(&a, stmts, 1, loc_at(1, 1));
     AstNode* fn = ast_make_function(&a, "main", NULL, 0, TYPE_I64, NULL, body, loc_at(1, 1));
     AstNode* fns[] = { fn };
-    AstNode* prog = ast_make_program(&a, fns, 1, NULL, 0, NULL, 0, loc_at(1, 1));
+    AstNode* prog = ast_make_program(&a, fns, 1, NULL, 0, NULL, 0, NULL, 0, loc_at(1, 1));
 
     const char* err = NULL;
     LLVMContextRef ctx3 = NULL;
@@ -108,7 +108,7 @@ void test_codegen_while_loop() {
     AstNode* fn_body = ast_make_block(&a, stmts, 2, loc_at(1, 1));
     AstNode* fn = ast_make_function(&a, "main", NULL, 0, TYPE_I64, NULL, fn_body, loc_at(1, 1));
     AstNode* fns[] = { fn };
-    AstNode* prog = ast_make_program(&a, fns, 1, NULL, 0, NULL, 0, loc_at(1, 1));
+    AstNode* prog = ast_make_program(&a, fns, 1, NULL, 0, NULL, 0, NULL, 0, loc_at(1, 1));
 
     const char* err = NULL;
     LLVMContextRef ctx4 = NULL;
@@ -162,7 +162,7 @@ void test_codegen_struct_decl() {
     AstNode* fn = ast_make_function(&a, "main", NULL, 0, TYPE_I64, NULL, body, loc_at(1, 1));
     AstNode* fns[] = { fn };
 
-    AstNode* prog = ast_make_program(&a, fns, 1, structs, 1, NULL, 0, loc_at(1, 1));
+    AstNode* prog = ast_make_program(&a, fns, 1, structs, 1, NULL, 0, NULL, 0, loc_at(1, 1));
 
     const char* err = NULL;
     LLVMContextRef ctx = NULL;
@@ -217,7 +217,7 @@ void test_codegen_struct_field_access() {
     AstNode* fn = ast_make_function(&a, "main", NULL, 0, TYPE_I64, NULL, body, loc_at(1, 1));
     AstNode* fns[] = { fn };
 
-    AstNode* prog = ast_make_program(&a, fns, 1, structs, 1, NULL, 0, loc_at(1, 1));
+    AstNode* prog = ast_make_program(&a, fns, 1, structs, 1, NULL, 0, NULL, 0, loc_at(1, 1));
 
     const char* err = NULL;
     LLVMContextRef ctx = NULL;
@@ -234,6 +234,56 @@ void test_codegen_struct_field_access() {
     arena_destroy(&a);
 }
 
+/* === enum 代码生成测试 === */
+
+void test_codegen_enum() {
+    Arena a = arena_create(1);
+
+    /* 构造 AST: enum Color { Red, Green, Blue }
+       fn main() -> i64 { let c = Color::Green; print_i64(c); return 0; } */
+    const char* cvariants[] = {"Red", "Green", "Blue"};
+    AstNode* enum_decl = ast_make_enum_decl(&a, "Color", cvariants, 3, loc_at(1, 1));
+    AstNode* enums[] = { enum_decl };
+
+    /* let c = Color::Green; */
+    AstNode* cv = ast_make_enum_variant(&a, "Color", "Green", loc_at(1, 1));
+    cv->as.enum_variant.variant_index = 1;  /* Green = index 1 */
+    cv->type.kind = TYPE_ENUM;
+
+    AstNode* let_stmt = ast_make_let(&a, "c", TYPE_UNKNOWN, false, false,
+                                      cv, NULL, loc_at(1, 1));
+
+    /* print_i64(c); */
+    AstNode* c_ident = ast_make_ident(&a, "c", loc_at(1, 1));
+    c_ident->type.kind = TYPE_ENUM;
+    AstNode* args[] = { c_ident };
+    AstNode* print_call = ast_make_call(&a, "print_i64", args, 1, loc_at(1, 1));
+
+    /* return 0; */
+    AstNode* ret = ast_make_return(&a, ast_make_literal_i64(&a, 0, loc_at(1, 1)), loc_at(1, 1));
+
+    AstNode* stmts[] = { let_stmt, print_call, ret };
+    AstNode* body = ast_make_block(&a, stmts, 3, loc_at(1, 1));
+    AstNode* fn = ast_make_function(&a, "main", NULL, 0, TYPE_I64, NULL, body, loc_at(1, 1));
+    AstNode* fns[] = { fn };
+
+    AstNode* prog = ast_make_program(&a, fns, 1, NULL, 0, NULL, 0, enums, 1, loc_at(1, 1));
+
+    const char* err = NULL;
+    LLVMContextRef ctx = NULL;
+    LLVMModuleRef mod = codegen_module(prog, &a, "test_enum", &err, &ctx);
+    ASSERT(mod != NULL);
+    ASSERT(err == NULL);
+
+    char* verify_err = NULL;
+    int failed = LLVMVerifyModule(mod, LLVMReturnStatusAction, &verify_err);
+    ASSERT(!failed);
+
+    LLVMDisposeModule(mod);
+    LLVMContextDispose(ctx);
+    arena_destroy(&a);
+}
+
 int main(void) {
     TEST_RUN(test_codegen_simple_function);
     TEST_RUN(test_codegen_if_else);
@@ -241,5 +291,6 @@ int main(void) {
     TEST_RUN(test_codegen_while_loop);
     TEST_RUN(test_codegen_struct_decl);
     TEST_RUN(test_codegen_struct_field_access);
+    TEST_RUN(test_codegen_enum);
     return test_summary();
 }

test/test_sema.c

@@ -223,6 +223,42 @@ void test_struct_nested_type_ok() {
     arena_destroy(&a);
 }
 
+/* === enum 语义分析测试 === */
+
+void test_enum_ok() {
+    Arena a = arena_create(1);
+    size_t tc; ErrorInfo lex_err = {0};
+    Token* toks = lex(&a,
+        "enum Color { Red, Green, Blue } fn main() { let c = Color::Green; print_i64(c); return; }",
+        "test", &tc, &lex_err);
+    ASSERT(toks != NULL);
+    ErrorInfo parse_err = {0};
+    AstNode* ast = parse(&a, toks, tc, "test", &parse_err);
+    ASSERT(ast != NULL);
+
+    ErrorList errors; error_init(&errors);
+    sema_analyze(ast, &errors, &a);
+    ASSERT(errors.count == 0);
+    arena_destroy(&a);
+}
+
+void test_enum_bad_variant() {
+    Arena a = arena_create(1);
+    size_t tc; ErrorInfo lex_err = {0};
+    Token* toks = lex(&a,
+        "enum Color { Red, Green, Blue } fn main() { let c = Color::Yellow; return; }",
+        "test", &tc, &lex_err);
+    ASSERT(toks != NULL);
+    ErrorInfo parse_err = {0};
+    AstNode* ast = parse(&a, toks, tc, "test", &parse_err);
+    ASSERT(ast != NULL);
+
+    ErrorList errors; error_init(&errors);
+    sema_analyze(ast, &errors, &a);
+    ASSERT(errors.count > 0);  // Yellow 不存在
+    arena_destroy(&a);
+}
+
 int main(void) {
     TEST_RUN(test_type_error);
     TEST_RUN(test_undefined_var);
@@ -237,5 +273,7 @@ int main(void) {
     TEST_RUN(test_struct_nested_type_ok);
     TEST_RUN(test_type_alias_ok);
     TEST_RUN(test_type_alias_struct);
+    TEST_RUN(test_enum_ok);
+    TEST_RUN(test_enum_bad_variant);
     return test_summary();
 }