MIRROR: javascript for 🐜's, a tiny runtime with big ambitions
...rest params
+164
-5
+83
-5
src/ant.c
+83
-5
src/ant.c
···
64
64
TOK_YIELD, TOK_UNDEF, TOK_NULL, TOK_TRUE, TOK_FALSE,
65
65
TOK_DOT = 100, TOK_CALL, TOK_BRACKET, TOK_POSTINC, TOK_POSTDEC, TOK_NOT, TOK_TILDA,
66
66
TOK_TYPEOF, TOK_UPLUS, TOK_UMINUS, TOK_EXP, TOK_MUL, TOK_DIV, TOK_REM,
67
-
TOK_OPTIONAL_CHAIN,
67
+
TOK_OPTIONAL_CHAIN, TOK_REST,
68
68
TOK_PLUS, TOK_MINUS, TOK_SHL, TOK_SHR, TOK_ZSHR, TOK_LT, TOK_LE, TOK_GT,
69
69
TOK_GE, TOK_EQ, TOK_NE, TOK_AND, TOK_XOR, TOK_OR, TOK_LAND, TOK_LOR,
70
70
TOK_COLON, TOK_Q, TOK_ASSIGN, TOK_PLUS_ASSIGN, TOK_MINUS_ASSIGN,
···
639
639
case ';': TOK(TOK_SEMICOLON, 1);
640
640
case ',': TOK(TOK_COMMA, 1);
641
641
case '!': if (LOOK(1, '=') && LOOK(2, '=')) TOK(TOK_NE, 3); if (LOOK(1, '=')) TOK(TOK_NE, 2); TOK(TOK_NOT, 1);
642
-
case '.': TOK(TOK_DOT, 1);
642
+
case '.': if (LOOK(1, '.') && LOOK(2, '.')) TOK(TOK_REST, 3); TOK(TOK_DOT, 1);
643
643
case '~': TOK(TOK_TILDA, 1);
644
644
case '-': if (LOOK(1, '-')) TOK(TOK_POSTDEC, 2); if (LOOK(1, '=')) TOK(TOK_MINUS_ASSIGN, 2); TOK(TOK_MINUS, 1);
645
645
case '+': if (LOOK(1, '+')) TOK(TOK_POSTINC, 2); if (LOOK(1, '=')) TOK(TOK_PLUS_ASSIGN, 2); TOK(TOK_PLUS, 1);
···
1063
1063
}
1064
1064
1065
1065
jsval_t function_scope = mkobj(js, parent_scope_offset);
1066
+
bool has_rest = false;
1067
+
jsoff_t rest_param_start = 0, rest_param_len = 0;
1068
+
1066
1069
while (fnpos < fnlen) {
1067
1070
fnpos = skiptonext(fn, fnlen, fnpos);
1068
1071
if (fnpos < fnlen && fn[fnpos] == ')') break;
1072
+
1073
+
bool is_rest = false;
1074
+
if (fnpos + 3 < fnlen && fn[fnpos] == '.' && fn[fnpos + 1] == '.' && fn[fnpos + 2] == '.') {
1075
+
is_rest = true;
1076
+
has_rest = true;
1077
+
fnpos += 3;
1078
+
fnpos = skiptonext(fn, fnlen, fnpos);
1079
+
}
1080
+
1069
1081
jsoff_t identlen = 0;
1070
1082
uint8_t tok = parseident(&fn[fnpos], fnlen - fnpos, &identlen);
1071
1083
if (tok != TOK_IDENTIFIER) break;
1084
+
1085
+
if (is_rest) {
1086
+
rest_param_start = fnpos;
1087
+
rest_param_len = identlen;
1088
+
fnpos = skiptonext(fn, fnlen, fnpos + identlen);
1089
+
break;
1090
+
}
1091
+
1072
1092
js->pos = skiptonext(js->code, js->clen, js->pos);
1073
1093
js->consumed = 1;
1074
1094
jsval_t v = js->code[js->pos] == ')' ? js_mkundef() : js_expr(js);
···
1079
1099
if (fnpos < fnlen && fn[fnpos] == ',') fnpos++;
1080
1100
}
1081
1101
1102
+
if (has_rest && rest_param_len > 0) {
1103
+
jsval_t rest_array = mkarr(js);
1104
+
if (!is_err(rest_array)) {
1105
+
jsoff_t idx = 0;
1106
+
js->pos = skiptonext(js->code, js->clen, js->pos);
1107
+
1108
+
while (js->pos < js->clen && js->code[js->pos] != ')') {
1109
+
js->consumed = 1;
1110
+
jsval_t arg = js_expr(js);
1111
+
if (!is_err(arg)) {
1112
+
char idxstr[16];
1113
+
snprintf(idxstr, sizeof(idxstr), "%u", (unsigned) idx);
1114
+
jsval_t key = js_mkstr(js, idxstr, strlen(idxstr));
1115
+
setprop(js, rest_array, key, resolveprop(js, arg));
1116
+
idx++;
1117
+
}
1118
+
js->pos = skiptonext(js->code, js->clen, js->pos);
1119
+
if (js->pos < js->clen && js->code[js->pos] == ',') js->pos++;
1120
+
}
1121
+
1122
+
jsval_t len_key = js_mkstr(js, "length", 6);
1123
+
setprop(js, rest_array, len_key, tov((double) idx));
1124
+
rest_array = mkval(T_ARR, vdata(rest_array));
1125
+
1126
+
setprop(js, function_scope, js_mkstr(js, &fn[rest_param_start], rest_param_len), rest_array);
1127
+
}
1128
+
}
1129
+
1082
1130
js->scope = function_scope;
1083
1131
if (fnpos < fnlen && fn[fnpos] == ')') fnpos++;
1084
1132
fnpos = skiptonext(fn, fnlen, fnpos);
···
1485
1533
jsoff_t pos = js->pos - 1;
1486
1534
for (bool comma = false; next(js) != TOK_EOF; comma = true) {
1487
1535
if (!comma && next(js) == TOK_RPAREN) break;
1488
-
EXPECT(TOK_IDENTIFIER, js->flags = flags);
1536
+
1537
+
bool is_rest = false;
1538
+
if (next(js) == TOK_REST) {
1539
+
is_rest = true;
1540
+
js->consumed = 1;
1541
+
next(js);
1542
+
}
1543
+
1544
+
if (next(js) != TOK_IDENTIFIER) {
1545
+
js->flags = flags;
1546
+
return js_mkerr(js, "identifier expected");
1547
+
}
1548
+
js->consumed = 1;
1549
+
1550
+
if (is_rest && next(js) != TOK_RPAREN) {
1551
+
js->flags = flags;
1552
+
return js_mkerr(js, "rest parameter must be last");
1553
+
}
1489
1554
if (next(js) == TOK_RPAREN) break;
1490
1555
EXPECT(TOK_COMMA, js->flags = flags);
1491
1556
}
···
1811
1876
else if (js->tok == TOK_RPAREN) paren_depth--;
1812
1877
1813
1878
if (paren_depth > 0) {
1814
-
if (js->tok != TOK_IDENTIFIER && js->tok != TOK_COMMA) could_be_arrow = false;
1879
+
if (js->tok != TOK_IDENTIFIER && js->tok != TOK_COMMA && js->tok != TOK_REST) could_be_arrow = false;
1815
1880
}
1816
1881
js->consumed = 1;
1817
1882
}
···
2296
2361
jsoff_t pos = js->pos - 1;
2297
2362
for (bool comma = false; next(js) != TOK_EOF; comma = true) {
2298
2363
if (!comma && next(js) == TOK_RPAREN) break;
2299
-
EXPECT(TOK_IDENTIFIER, );
2364
+
2365
+
bool is_rest = false;
2366
+
if (next(js) == TOK_REST) {
2367
+
is_rest = true;
2368
+
js->consumed = 1;
2369
+
next(js);
2370
+
}
2371
+
2372
+
if (next(js) != TOK_IDENTIFIER) return js_mkerr(js, "identifier expected");
2373
+
js->consumed = 1;
2374
+
2375
+
if (is_rest && next(js) != TOK_RPAREN) {
2376
+
return js_mkerr(js, "rest parameter must be last");
2377
+
}
2300
2378
if (next(js) == TOK_RPAREN) break;
2301
2379
EXPECT(TOK_COMMA, );
2302
2380
}
+81
tests/test_rest_params.cjs
+81
tests/test_rest_params.cjs
···
1
+
// Test rest parameters in function definitions
2
+
3
+
// Test 1: Basic rest parameter
4
+
function sum(...numbers) {
5
+
let total = 0;
6
+
for (let i = 0; i < numbers.length; i++) {
7
+
total = total + numbers[i];
8
+
}
9
+
return total;
10
+
}
11
+
12
+
Ant.println("Test 1 - Basic rest params:");
13
+
Ant.println(sum(1, 2, 3, 4, 5)); // Should print 15
14
+
15
+
// Test 2: Rest parameter with regular parameters
16
+
function greet(greeting, ...names) {
17
+
let result = greeting;
18
+
for (let i = 0; i < names.length; i++) {
19
+
result = result + " " + names[i];
20
+
}
21
+
return result;
22
+
}
23
+
24
+
Ant.println("\nTest 2 - Rest params with regular params:");
25
+
Ant.println(greet("Hello", "Alice", "Bob", "Charlie")); // Should print "Hello Alice Bob Charlie"
26
+
27
+
// Test 3: Rest parameter with no arguments passed
28
+
function noArgs(...args) {
29
+
return args.length;
30
+
}
31
+
32
+
Ant.println("\nTest 3 - Rest params with no args:");
33
+
Ant.println(noArgs()); // Should print 0
34
+
35
+
// Test 4: Rest parameter with single argument
36
+
function singleArg(...args) {
37
+
return args[0];
38
+
}
39
+
40
+
Ant.println("\nTest 4 - Rest params with single arg:");
41
+
Ant.println(singleArg(42)); // Should print 42
42
+
43
+
// Test 5: Arrow function with rest parameters
44
+
const multiply = (...factors) => {
45
+
let result = 1;
46
+
for (let i = 0; i < factors.length; i++) {
47
+
result = result * factors[i];
48
+
}
49
+
return result;
50
+
};
51
+
52
+
Ant.println("\nTest 5 - Arrow function with rest params:");
53
+
Ant.println(multiply(2, 3, 4)); // Should print 24
54
+
55
+
// Test 6: Multiple regular params with rest
56
+
function compute(operation, initial, ...values) {
57
+
let result = initial;
58
+
if (operation === "add") {
59
+
for (let i = 0; i < values.length; i++) {
60
+
result = result + values[i];
61
+
}
62
+
}
63
+
if (operation === "multiply") {
64
+
for (let i = 0; i < values.length; i++) {
65
+
result = result * values[i];
66
+
}
67
+
}
68
+
return result;
69
+
}
70
+
71
+
Ant.println("\nTest 6 - Multiple params with rest:");
72
+
Ant.println(compute("add", 10, 5, 3, 2)); // Should print 20
73
+
Ant.println(compute("multiply", 2, 3, 4)); // Should print 24
74
+
75
+
// Test 7: Rest parameter is an actual array
76
+
function checkArray(...items) {
77
+
return items.length;
78
+
}
79
+
80
+
Ant.println("\nTest 7 - Rest param is array:");
81
+
Ant.println(checkArray("a", "b", "c", "d")); // Should print 4