frontend: update parser api usage with diagnostic support

frontend/cmd/compile.c

@@ -98,6 +98,8 @@ static int compile_file(const char *path, const b_arglist *args)
 		return -1;
 	}
 
+	ivy_parser_set_diag_ctx(parser, diag);
+
 	struct mie_ctx *ctx = mie_ctx_create();
 
 	struct ivy_codegen *codegen;
@@ -135,6 +137,13 @@ static int compile_file(const char *path, const b_arglist *args)
 
 		status = ivy_parser_push_token(parser, tok);
 
+		if (status == IVY_ERR_BAD_SYNTAX) {
+			ivy_diag_ctx_write(
+				diag, IVY_DIAG_FORMAT_PRETTY, &diag_stream);
+			ivy_token_destroy(tok);
+			break;
+		}
+
 		if (status != IVY_OK) {
 			b_err("failed to parse '%s'", path);
 			b_i("reason: parse error (%s)",