feat: add if/else blocks

if now guards a { } block or bare statement with an optional else (and
now else-if chaining). The branch body becomes a statement list; a bare
guarded statement is a list of length one.

2 files changed, 63 insertions, 0 deletions

diff --git a/tests/codegen_test.c b/tests/codegen_test.c
index 8fe1465..db23791 100644
--- a/tests/codegen_test.c
+++ b/tests/codegen_test.c
@@ -80,6 +80,26 @@ static void test_generate_if(struct TestContext* context)
 	free_program(&program);
 }
 
+static void test_generate_if_else(struct TestContext* context)
+{
+	struct Lexer lexer = create_lexer(
+		"proc main\n{\nif rax > 3\n{\nrdi = 1\n}\nelse\n{\nrdi = 0\n}\n}\n");
+	struct Program program;
+	check(context, parse_program(&lexer, &program));
+
+	char buffer[1024];
+	generate_to_buffer(&program, buffer, sizeof(buffer));
+
+	check(context, strstr(buffer, "jle .if_else_0") != NULL);
+	check(context, strstr(buffer, "mov rdi, 1") != NULL);
+	check(context, strstr(buffer, "jmp .if_end_0") != NULL);
+	check(context, strstr(buffer, ".if_else_0:") != NULL);
+	check(context, strstr(buffer, "mov rdi, 0") != NULL);
+	check(context, strstr(buffer, ".if_end_0:") != NULL);
+
+	free_program(&program);
+}
+
 static void test_generate_call(struct TestContext* context)
 {
 	struct Lexer lexer = create_lexer(
@@ -428,6 +448,7 @@ void run_codegen_tests(struct TestContext* context)
 	test_generate_consts_and_data(context);
 	test_generate_text(context);
 	test_generate_if(context);
+	test_generate_if_else(context);
 	test_generate_call(context);
 	test_generate_param_substitution(context);
 	test_generate_divide(context);
diff --git a/tests/parser_test.c b/tests/parser_test.c
index ca1d345..32ea422 100644
--- a/tests/parser_test.c
+++ b/tests/parser_test.c
@@ -160,8 +160,48 @@ static void test_parse_if(struct TestContext* context)
 	check(context, primary_is(branch.branch.left, "rax"));
 	check(context, text_is(branch.branch.comparison, "!="));
 	check(context, primary_is(branch.branch.right, "0"));
+	check(context, branch.branch.body_count == 1);
 	check(context, branch.branch.body->kind == STATEMENT_GOTO);
 	check(context, text_is(branch.branch.body->jump.label, "loop"));
+	check(context, branch.branch.else_count == 0);
+
+	free_program(&program);
+}
+
+static void test_parse_if_block(struct TestContext* context)
+{
+	struct Lexer lexer = create_lexer(
+		"proc main\n{\nif rax > 3\n{\nrdi = 1\nrbx = 2\n}\nelse\n{\nrdi = 0\n}\n}\n");
+	struct Program program;
+
+	check(context, parse_program(&lexer, &program));
+	check(context, program.procs[0].body_count == 1);
+
+	struct Statement branch = program.procs[0].body[0];
+	check(context, branch.kind == STATEMENT_IF);
+	check(context, branch.branch.body_count == 2);
+	check(context, branch.branch.body[0].kind == STATEMENT_ASSIGN);
+	check(context, text_is(branch.branch.body[1].assign.target, "rbx"));
+	check(context, branch.branch.else_count == 1);
+	check(context, text_is(branch.branch.else_body[0].assign.target, "rdi"));
+
+	free_program(&program);
+}
+
+static void test_parse_else_if(struct TestContext* context)
+{
+	struct Lexer lexer = create_lexer(
+		"proc main\n{\nif rax == 0\nrdi = 1\nelse if rax == 1\nrdi = 2\n}\n");
+	struct Program program;
+
+	check(context, parse_program(&lexer, &program));
+
+	struct Statement branch = program.procs[0].body[0];
+	check(context, branch.kind == STATEMENT_IF);
+	check(context, branch.branch.body_count == 1);
+	check(context, branch.branch.else_count == 1);
+	check(context, branch.branch.else_body[0].kind == STATEMENT_IF);
+	check(context, primary_is(branch.branch.else_body[0].branch.right, "1"));
 
 	free_program(&program);
 }
@@ -315,6 +355,8 @@ void run_parser_tests(struct TestContext* context)
 	test_parse_simple_statements(context);
 	test_parse_expressions(context);
 	test_parse_if(context);
+	test_parse_if_block(context);
+	test_parse_else_if(context);
 	test_parse_call(context);
 	test_parse_stack(context);
 	test_parse_sized_deref(context);