commit df8a7eef31456a4fedd5bc8b40b414a99c9d84c8
parent 15dd556f5ec586d4689848b2ada91183ed4ce71e
Author: Fabrice Bellard <fabrice@bellard.org>
Date: Sat, 27 Jan 2024 13:12:54 +0100
simplified and fixed arrow function parsing (github issue #226)
Diffstat:
2 files changed, 67 insertions(+), 46 deletions(-)
diff --git a/quickjs/quickjs.c b/quickjs/quickjs.c
@@ -22869,12 +22869,10 @@ static __exception int js_parse_object_literal(JSParseState *s)
#define PF_IN_ACCEPTED (1 << 0)
/* allow function calls parsing in js_parse_postfix_expr() */
#define PF_POSTFIX_CALL (1 << 1)
-/* allow arrow functions parsing in js_parse_postfix_expr() */
-#define PF_ARROW_FUNC (1 << 2)
/* allow the exponentiation operator in js_parse_unary() */
-#define PF_POW_ALLOWED (1 << 3)
+#define PF_POW_ALLOWED (1 << 2)
/* forbid the exponentiation operator in js_parse_unary() */
-#define PF_POW_FORBIDDEN (1 << 4)
+#define PF_POW_FORBIDDEN (1 << 3)
static __exception int js_parse_postfix_expr(JSParseState *s, int parse_flags);
@@ -24486,7 +24484,7 @@ static void optional_chain_test(JSParseState *s, int *poptional_chaining_label,
emit_label(s, label_next);
}
-/* allowed parse_flags: PF_POSTFIX_CALL, PF_ARROW_FUNC */
+/* allowed parse_flags: PF_POSTFIX_CALL */
static __exception int js_parse_postfix_expr(JSParseState *s, int parse_flags)
{
FuncCallType call_type;
@@ -24589,16 +24587,8 @@ static __exception int js_parse_postfix_expr(JSParseState *s, int parse_flags)
}
break;
case '(':
- if ((parse_flags & PF_ARROW_FUNC) &&
- js_parse_skip_parens_token(s, NULL, TRUE) == TOK_ARROW) {
- if (js_parse_function_decl(s, JS_PARSE_FUNC_ARROW,
- JS_FUNC_NORMAL, JS_ATOM_NULL,
- s->token.ptr, s->token.line_num))
- return -1;
- } else {
- if (js_parse_expr_paren(s))
- return -1;
- }
+ if (js_parse_expr_paren(s))
+ return -1;
break;
case TOK_FUNCTION:
if (js_parse_function_decl(s, JS_PARSE_FUNC_EXPR,
@@ -24638,14 +24628,8 @@ static __exception int js_parse_postfix_expr(JSParseState *s, int parse_flags)
if (s->token.u.ident.is_reserved) {
return js_parse_error_reserved_identifier(s);
}
- if ((parse_flags & PF_ARROW_FUNC) &&
- peek_token(s, TRUE) == TOK_ARROW) {
- if (js_parse_function_decl(s, JS_PARSE_FUNC_ARROW,
- JS_FUNC_NORMAL, JS_ATOM_NULL,
- s->token.ptr, s->token.line_num))
- return -1;
- } else if (token_is_pseudo_keyword(s, JS_ATOM_async) &&
- peek_token(s, TRUE) != '\n') {
+ if (token_is_pseudo_keyword(s, JS_ATOM_async) &&
+ peek_token(s, TRUE) != '\n') {
const uint8_t *source_ptr;
int source_line_num;
@@ -24658,15 +24642,6 @@ static __exception int js_parse_postfix_expr(JSParseState *s, int parse_flags)
JS_FUNC_ASYNC, JS_ATOM_NULL,
source_ptr, source_line_num))
return -1;
- } else if ((parse_flags & PF_ARROW_FUNC) &&
- ((s->token.val == '(' &&
- js_parse_skip_parens_token(s, NULL, TRUE) == TOK_ARROW) ||
- (s->token.val == TOK_IDENT && !s->token.u.ident.is_reserved &&
- peek_token(s, TRUE) == TOK_ARROW))) {
- if (js_parse_function_decl(s, JS_PARSE_FUNC_ARROW,
- JS_FUNC_ASYNC, JS_ATOM_NULL,
- source_ptr, source_line_num))
- return -1;
} else {
name = JS_DupAtom(s->ctx, JS_ATOM_async);
goto do_get_var;
@@ -25270,7 +25245,7 @@ static __exception int js_parse_delete(JSParseState *s)
return 0;
}
-/* allowed parse_flags: PF_ARROW_FUNC, PF_POW_ALLOWED, PF_POW_FORBIDDEN */
+/* allowed parse_flags: PF_POW_ALLOWED, PF_POW_FORBIDDEN */
static __exception int js_parse_unary(JSParseState *s, int parse_flags)
{
int op;
@@ -25361,8 +25336,7 @@ static __exception int js_parse_unary(JSParseState *s, int parse_flags)
parse_flags = 0;
break;
default:
- if (js_parse_postfix_expr(s, (parse_flags & PF_ARROW_FUNC) |
- PF_POSTFIX_CALL))
+ if (js_parse_postfix_expr(s, PF_POSTFIX_CALL))
return -1;
if (!s->got_lf &&
(s->token.val == TOK_DEC || s->token.val == TOK_INC)) {
@@ -25419,15 +25393,14 @@ static __exception int js_parse_unary(JSParseState *s, int parse_flags)
return 0;
}
-/* allowed parse_flags: PF_ARROW_FUNC, PF_IN_ACCEPTED */
+/* allowed parse_flags: PF_IN_ACCEPTED */
static __exception int js_parse_expr_binary(JSParseState *s, int level,
int parse_flags)
{
int op, opcode;
if (level == 0) {
- return js_parse_unary(s, (parse_flags & PF_ARROW_FUNC) |
- PF_POW_ALLOWED);
+ return js_parse_unary(s, PF_POW_ALLOWED);
} else if (s->token.val == TOK_PRIVATE_NAME &&
(parse_flags & PF_IN_ACCEPTED) && level == 4 &&
peek_token(s, FALSE) == TOK_IN) {
@@ -25440,7 +25413,7 @@ static __exception int js_parse_expr_binary(JSParseState *s, int level,
goto fail_private_in;
if (next_token(s))
goto fail_private_in;
- if (js_parse_expr_binary(s, level - 1, parse_flags & ~PF_ARROW_FUNC)) {
+ if (js_parse_expr_binary(s, level - 1, parse_flags)) {
fail_private_in:
JS_FreeAtom(s->ctx, atom);
return -1;
@@ -25582,14 +25555,14 @@ static __exception int js_parse_expr_binary(JSParseState *s, int level,
}
if (next_token(s))
return -1;
- if (js_parse_expr_binary(s, level - 1, parse_flags & ~PF_ARROW_FUNC))
+ if (js_parse_expr_binary(s, level - 1, parse_flags))
return -1;
emit_op(s, opcode);
}
return 0;
}
-/* allowed parse_flags: PF_ARROW_FUNC, PF_IN_ACCEPTED */
+/* allowed parse_flags: PF_IN_ACCEPTED */
static __exception int js_parse_logical_and_or(JSParseState *s, int op,
int parse_flags)
{
@@ -25613,11 +25586,11 @@ static __exception int js_parse_logical_and_or(JSParseState *s, int op,
emit_op(s, OP_drop);
if (op == TOK_LAND) {
- if (js_parse_expr_binary(s, 8, parse_flags & ~PF_ARROW_FUNC))
+ if (js_parse_expr_binary(s, 8, parse_flags))
return -1;
} else {
if (js_parse_logical_and_or(s, TOK_LAND,
- parse_flags & ~PF_ARROW_FUNC))
+ parse_flags))
return -1;
}
if (s->token.val != op) {
@@ -25649,7 +25622,7 @@ static __exception int js_parse_coalesce_expr(JSParseState *s, int parse_flags)
emit_goto(s, OP_if_false, label1);
emit_op(s, OP_drop);
- if (js_parse_expr_binary(s, 8, parse_flags & ~PF_ARROW_FUNC))
+ if (js_parse_expr_binary(s, 8, parse_flags))
return -1;
if (s->token.val != TOK_DOUBLE_QUESTION_MARK)
break;
@@ -25659,7 +25632,7 @@ static __exception int js_parse_coalesce_expr(JSParseState *s, int parse_flags)
return 0;
}
-/* allowed parse_flags: PF_ARROW_FUNC, PF_IN_ACCEPTED */
+/* allowed parse_flags: PF_IN_ACCEPTED */
static __exception int js_parse_cond_expr(JSParseState *s, int parse_flags)
{
int label1, label2;
@@ -25834,12 +25807,50 @@ static __exception int js_parse_assign_expr2(JSParseState *s, int parse_flags)
emit_label(s, label_next);
}
return 0;
+ } else if (s->token.val == '(' &&
+ js_parse_skip_parens_token(s, NULL, TRUE) == TOK_ARROW) {
+ return js_parse_function_decl(s, JS_PARSE_FUNC_ARROW,
+ JS_FUNC_NORMAL, JS_ATOM_NULL,
+ s->token.ptr, s->token.line_num);
+ } else if (token_is_pseudo_keyword(s, JS_ATOM_async)) {
+ const uint8_t *source_ptr;
+ int source_line_num, tok;
+ JSParsePos pos;
+
+ /* fast test */
+ tok = peek_token(s, TRUE);
+ if (tok == TOK_FUNCTION || tok == '\n')
+ goto next;
+
+ source_ptr = s->token.ptr;
+ source_line_num = s->token.line_num;
+ js_parse_get_pos(s, &pos);
+ if (next_token(s))
+ return -1;
+ if ((s->token.val == '(' &&
+ js_parse_skip_parens_token(s, NULL, TRUE) == TOK_ARROW) ||
+ (s->token.val == TOK_IDENT && !s->token.u.ident.is_reserved &&
+ peek_token(s, TRUE) == TOK_ARROW)) {
+ return js_parse_function_decl(s, JS_PARSE_FUNC_ARROW,
+ JS_FUNC_ASYNC, JS_ATOM_NULL,
+ source_ptr, source_line_num);
+ } else {
+ /* undo the token parsing */
+ if (js_parse_seek_token(s, &pos))
+ return -1;
+ }
+ } else if (s->token.val == TOK_IDENT &&
+ peek_token(s, TRUE) == TOK_ARROW) {
+ return js_parse_function_decl(s, JS_PARSE_FUNC_ARROW,
+ JS_FUNC_NORMAL, JS_ATOM_NULL,
+ s->token.ptr, s->token.line_num);
}
+ next:
if (s->token.val == TOK_IDENT) {
/* name0 is used to check for OP_set_name pattern, not duplicated */
name0 = s->token.u.ident.atom;
}
- if (js_parse_cond_expr(s, parse_flags | PF_ARROW_FUNC))
+ if (js_parse_cond_expr(s, parse_flags))
return -1;
op = s->token.val;
diff --git a/quickjs/tests/test_language.js b/quickjs/tests/test_language.js
@@ -558,6 +558,15 @@ function test_parse_semicolon()
}
}
+function test_parse_arrow_function()
+{
+ assert(typeof eval("() => {}\n() => {}"), "function");
+ assert(eval("() => {}\n+1"), 1);
+ assert(typeof eval("x => {}\n() => {}"), "function");
+ assert(typeof eval("async () => {}\n() => {}"), "function");
+ assert(typeof eval("async x => {}\n() => {}"), "function");
+}
+
/* optional chaining tests not present in test262 */
function test_optional_chaining()
{
@@ -604,3 +613,4 @@ test_argument_scope();
test_function_expr_name();
test_parse_semicolon();
test_optional_chaining();
+test_parse_arrow_function();
