MIRROR: javascript for 🐜's, a tiny runtime with big ambitions
implement enhanced destructuring pattern support for arrays and objects
+264
-36
+264
-36
src/ant.c
+264
-36
src/ant.c
···
6699
6699
return pos;
6700
6700
}
6701
6701
6702
+
static jsoff_t destruct_source_len(struct js *js, jsval_t val) {
6703
+
if (vtype(val) == T_STR) {
6704
+
size_t slen = 0;
6705
+
(void)js_getstr(js, val, &slen);
6706
+
return (jsoff_t)slen;
6707
+
}
6708
+
return js_arr_len(js, val);
6709
+
}
6710
+
6711
+
static jsval_t destruct_source_get(struct js *js, jsval_t val, jsoff_t idx) {
6712
+
if (vtype(val) == T_STR) {
6713
+
size_t slen = 0;
6714
+
char *s = js_getstr(js, val, &slen);
6715
+
if ((size_t)idx >= slen) return js_mkundef();
6716
+
return js_mkstr(js, &s[idx], 1);
6717
+
}
6718
+
return js_arr_get(js, val, idx);
6719
+
}
6720
+
6721
+
static jsval_t destruct_get_by_key(struct js *js, jsval_t obj, jsval_t key) {
6722
+
if (!is_object_type(obj)) return js_mkerr(js, "invalid assignment target");
6723
+
if (vtype(key) == T_SYMBOL) {
6724
+
char sym_buf[32];
6725
+
int klen = sym_to_prop_key(key, sym_buf, sizeof(sym_buf));
6726
+
if (klen < 0) return js_mkerr(js, "invalid symbol key");
6727
+
return getprop_any(js, obj, sym_buf, (size_t)klen);
6728
+
}
6729
+
jsval_t key_str = coerce_to_str(js, key);
6730
+
if (is_err(key_str)) return key_str;
6731
+
jsoff_t klen = 0, koff = vstr(js, key_str, &klen);
6732
+
return getprop_any(js, obj, (const char *)&js->mem[koff], (size_t)klen);
6733
+
}
6734
+
6735
+
static jsval_t destruct_set_by_key(struct js *js, jsval_t obj, jsval_t key, jsval_t value) {
6736
+
if (!is_object_type(obj)) return js_mkerr(js, "invalid assignment target");
6737
+
if (vtype(key) == T_SYMBOL) {
6738
+
char sym_buf[32];
6739
+
int klen = sym_to_prop_key(key, sym_buf, sizeof(sym_buf));
6740
+
if (klen < 0) return js_mkerr(js, "invalid symbol key");
6741
+
return js_setprop(js, obj, js_mkstr(js, sym_buf, (size_t)klen), value);
6742
+
}
6743
+
jsval_t key_str = coerce_to_str(js, key);
6744
+
if (is_err(key_str)) return key_str;
6745
+
return js_setprop(js, obj, key_str, value);
6746
+
}
6747
+
6748
+
static bool scan_balanced_with_strings(const char *p, jsoff_t len, jsoff_t *pos, char open, char close) {
6749
+
if (*pos >= len || p[*pos] != open) return false;
6750
+
6751
+
int depth = 1;
6752
+
bool in_string = false;
6753
+
char string_char = '\0';
6754
+
(*pos)++;
6755
+
6756
+
while (*pos < len && depth > 0) {
6757
+
char ch = p[*pos];
6758
+
if (in_string) {
6759
+
if (ch == '\\' && *pos + 1 < len) {
6760
+
*pos += 2;
6761
+
continue;
6762
+
}
6763
+
if (ch == string_char) {
6764
+
in_string = false;
6765
+
string_char = '\0';
6766
+
}
6767
+
(*pos)++;
6768
+
continue;
6769
+
}
6770
+
if (ch == '"' || ch == '\'' || ch == '`') {
6771
+
in_string = true;
6772
+
string_char = ch;
6773
+
(*pos)++;
6774
+
continue;
6775
+
}
6776
+
if (ch == open) depth++;
6777
+
else if (ch == close) depth--;
6778
+
(*pos)++;
6779
+
}
6780
+
return depth == 0;
6781
+
}
6782
+
6783
+
static jsval_t parse_nested_pattern_span(
6784
+
struct js *js, const char *p, jsoff_t len, jsoff_t *pos,
6785
+
jsoff_t *out_start, jsoff_t *out_len
6786
+
) {
6787
+
char open = p[*pos];
6788
+
char close = (open == '[') ? ']' : '}';
6789
+
6790
+
*out_start = *pos;
6791
+
if (!scan_balanced_with_strings(p, len, pos, open, close)) {
6792
+
return js_mkerr_typed(js, JS_ERR_SYNTAX, "unclosed nested destructuring pattern");
6793
+
}
6794
+
*out_len = *pos - *out_start;
6795
+
return js_mkundef();
6796
+
}
6797
+
6798
+
static jsval_t eval_computed_key_expr(
6799
+
struct js *js, const char *p, jsoff_t len, jsoff_t *pos, const char *unclosed_msg
6800
+
) {
6801
+
jsoff_t expr_start = *pos + 1;
6802
+
if (!scan_balanced_with_strings(p, len, pos, '[', ']')) {
6803
+
return js_mkerr_typed(js, JS_ERR_SYNTAX, "%s", unclosed_msg);
6804
+
}
6805
+
6806
+
jsoff_t expr_end = *pos - 1;
6807
+
jsval_t key = js_eval_str(js, &p[expr_start], expr_end - expr_start);
6808
+
if (is_err(key)) return key;
6809
+
return resolveprop(js, key);
6810
+
}
6811
+
6812
+
static jsval_t extend_destruct_target_span(
6813
+
struct js *js, const char *p, jsoff_t len, jsoff_t target_pos,
6814
+
jsoff_t *target_len, jsoff_t *out_pos
6815
+
) {
6816
+
jsoff_t pos = skiptonext(p, len, target_pos + *target_len, NULL);
6817
+
6818
+
while (pos < len && (p[pos] == '.' || p[pos] == '[')) {
6819
+
if (p[pos] == '.') {
6820
+
pos = skiptonext(p, len, pos + 1, NULL);
6821
+
jsoff_t ident_len = 0;
6822
+
if (parseident(&p[pos], len - pos, &ident_len) != TOK_IDENTIFIER) {
6823
+
return js_mkerr_typed(js, JS_ERR_SYNTAX, "identifier expected after '.'");
6824
+
}
6825
+
pos += ident_len;
6826
+
pos = skiptonext(p, len, pos, NULL);
6827
+
*target_len = pos - target_pos;
6828
+
continue;
6829
+
}
6830
+
6831
+
if (!scan_balanced_with_strings(p, len, &pos, '[', ']')) {
6832
+
return js_mkerr_typed(js, JS_ERR_SYNTAX, "']' expected");
6833
+
}
6834
+
pos = skiptonext(p, len, pos, NULL);
6835
+
*target_len = pos - target_pos;
6836
+
}
6837
+
6838
+
*out_pos = pos;
6839
+
return js_mkundef();
6840
+
}
6841
+
6842
+
static jsval_t make_destruct_rest_array(struct js *js, jsval_t val, jsoff_t start_idx) {
6843
+
jsval_t rest = js_mkarr(js);
6844
+
if (is_err(rest)) return rest;
6845
+
6846
+
jsoff_t alen = destruct_source_len(js, val);
6847
+
for (jsoff_t i = start_idx; i < alen; i++) {
6848
+
js_arr_push(js, rest, destruct_source_get(js, val, i));
6849
+
}
6850
+
return rest;
6851
+
}
6852
+
6853
+
static jsval_t assign_destruct_target(struct js *js, const char *p, jsoff_t len, jsval_t value, jsval_t scope) {
6854
+
jsoff_t pos = skiptonext(p, len, 0, NULL);
6855
+
jsoff_t base_len = 0;
6856
+
if (parseident(&p[pos], len - pos, &base_len) != TOK_IDENTIFIER) {
6857
+
return js_mkerr_typed(js, JS_ERR_SYNTAX, "invalid assignment target in destructuring");
6858
+
}
6859
+
6860
+
jsoff_t base_pos = pos;
6861
+
pos += base_len;
6862
+
pos = skiptonext(p, len, pos, NULL);
6863
+
if (pos >= len) {
6864
+
jsval_t vname = js_mkstr(js, &p[base_pos], base_len);
6865
+
return js_setprop(js, scope, vname, value);
6866
+
}
6867
+
6868
+
jsval_t cur = getprop_any(js, scope, &p[base_pos], (size_t)base_len);
6869
+
if (is_err(cur)) return cur;
6870
+
6871
+
while (pos < len) {
6872
+
if (p[pos] == '.') {
6873
+
pos = skiptonext(p, len, pos + 1, NULL);
6874
+
jsoff_t nlen = 0;
6875
+
if (parseident(&p[pos], len - pos, &nlen) != TOK_IDENTIFIER) {
6876
+
return js_mkerr_typed(js, JS_ERR_SYNTAX, "identifier expected after '.'");
6877
+
}
6878
+
jsval_t key = js_mkstr(js, &p[pos], nlen);
6879
+
pos += nlen;
6880
+
pos = skiptonext(p, len, pos, NULL);
6881
+
if (pos >= len) return destruct_set_by_key(js, cur, key, value);
6882
+
cur = destruct_get_by_key(js, cur, key);
6883
+
if (is_err(cur)) return cur;
6884
+
continue;
6885
+
}
6886
+
6887
+
if (p[pos] == '[') {
6888
+
jsval_t key = eval_computed_key_expr(js, p, len, &pos, "']' expected");
6889
+
if (is_err(key)) return key;
6890
+
pos = skiptonext(p, len, pos, NULL);
6891
+
if (pos >= len) return destruct_set_by_key(js, cur, key, value);
6892
+
cur = destruct_get_by_key(js, cur, key);
6893
+
if (is_err(cur)) return cur;
6894
+
continue;
6895
+
}
6896
+
6897
+
return js_mkerr_typed(js, JS_ERR_SYNTAX, "invalid assignment target in destructuring");
6898
+
}
6899
+
return js_mkundef();
6900
+
}
6901
+
6702
6902
static jsval_t bind_destruct_pattern(struct js *js, const char *p, jsoff_t len, jsval_t val, jsval_t scope) {
6703
6903
jsoff_t pos = skiptonext(p, len, 0, NULL);
6704
6904
if (pos >= len) return js_mkundef();
···
6716
6916
if (p[pos] == ',') { pos++; idx++; continue; }
6717
6917
6718
6918
if (is_arr && (p[pos] == '[' || p[pos] == '{')) {
6719
-
jsoff_t nested_start = pos;
6720
-
char open = p[pos], close = (open == '[') ? ']' : '}';
6721
-
int depth = 1;
6722
-
pos++;
6723
-
while (pos < len && depth > 0) {
6724
-
if (p[pos] == open) depth++;
6725
-
else if (p[pos] == close) depth--;
6726
-
pos++;
6727
-
}
6728
-
jsoff_t nested_len = pos - nested_start;
6729
-
jsval_t elem_val = js_arr_get(js, val, idx);
6919
+
jsoff_t nested_start = 0, nested_len = 0;
6920
+
jsval_t nested_res = parse_nested_pattern_span(js, p, len, &pos, &nested_start, &nested_len);
6921
+
if (is_err(nested_res)) return nested_res;
6922
+
6923
+
jsval_t elem_val = destruct_source_get(js, val, idx);
6730
6924
jsval_t r = bind_destruct_pattern(js, &p[nested_start], nested_len, elem_val, scope);
6731
6925
if (is_err(r)) return r;
6732
6926
idx++;
···
6737
6931
6738
6932
bool is_rest = (pos + 2 < len && p[pos] == '.' && p[pos+1] == '.' && p[pos+2] == '.');
6739
6933
if (is_rest) { pos += 3; pos = skiptonext(p, len, pos, NULL); }
6934
+
6935
+
if (is_arr && is_rest && pos < len && (p[pos] == '[' || p[pos] == '{')) {
6936
+
jsoff_t nested_start = 0, nested_len = 0;
6937
+
jsval_t nested_res = parse_nested_pattern_span(js, p, len, &pos, &nested_start, &nested_len);
6938
+
if (is_err(nested_res)) return nested_res;
6939
+
6940
+
jsval_t rest = make_destruct_rest_array(js, val, idx);
6941
+
if (is_err(rest)) return rest;
6942
+
6943
+
jsval_t r = bind_destruct_pattern(js, &p[nested_start], nested_len, rest, scope);
6944
+
if (is_err(r)) return r;
6945
+
6946
+
idx = (int)destruct_source_len(js, val);
6947
+
pos = skiptonext(p, len, pos, NULL);
6948
+
if (pos < len && p[pos] == ',') pos++;
6949
+
continue;
6950
+
}
6740
6951
6952
+
bool has_computed_key = false;
6953
+
jsval_t computed_key = js_mkundef();
6741
6954
jsoff_t name_len = 0;
6742
-
if (parseident(&p[pos], len - pos, &name_len) != TOK_IDENTIFIER) break;
6743
-
6744
-
jsoff_t var_pos = pos, var_len = name_len;
6745
-
jsoff_t src_pos = pos, src_len = name_len;
6746
-
6747
-
pos += name_len;
6955
+
jsoff_t var_pos = 0, var_len = 0;
6956
+
jsoff_t src_pos = 0, src_len = 0;
6957
+
jsoff_t target_pos = 0, target_len = 0;
6958
+
6959
+
if (!is_arr && p[pos] == '[') {
6960
+
has_computed_key = true;
6961
+
computed_key = eval_computed_key_expr(js, p, len, &pos, "unclosed computed property name");
6962
+
if (is_err(computed_key)) return computed_key;
6963
+
} else {
6964
+
if (parseident(&p[pos], len - pos, &name_len) != TOK_IDENTIFIER) break;
6965
+
var_pos = pos;
6966
+
var_len = name_len;
6967
+
src_pos = pos;
6968
+
src_len = name_len;
6969
+
target_pos = pos;
6970
+
target_len = name_len;
6971
+
pos += name_len;
6972
+
}
6748
6973
pos = skiptonext(p, len, pos, NULL);
6749
6974
6750
6975
bool is_nested = false;
···
6755
6980
6756
6981
if (pos < len && (p[pos] == '{' || p[pos] == '[')) {
6757
6982
is_nested = true;
6758
-
nested_start = pos;
6759
-
char open = p[pos], close = (open == '{') ? '}' : ']';
6760
-
int depth = 1;
6761
-
pos++;
6762
-
while (pos < len && depth > 0) {
6763
-
if (p[pos] == open) depth++;
6764
-
else if (p[pos] == close) depth--;
6765
-
pos++;
6766
-
}
6767
-
nested_len = pos - nested_start;
6983
+
jsval_t nested_res = parse_nested_pattern_span(js, p, len, &pos, &nested_start, &nested_len);
6984
+
if (is_err(nested_res)) return nested_res;
6768
6985
pos = skiptonext(p, len, pos, NULL);
6769
6986
} else {
6770
6987
jsoff_t rlen = 0;
6771
6988
if (parseident(&p[pos], len - pos, &rlen) == TOK_IDENTIFIER) {
6772
6989
var_pos = pos; var_len = rlen;
6990
+
target_pos = pos; target_len = rlen;
6773
6991
pos += rlen;
6774
6992
pos = skiptonext(p, len, pos, NULL);
6775
6993
}
6776
6994
}
6995
+
} else if (!is_arr && has_computed_key) {
6996
+
return js_mkerr(js, "':' expected after computed property name");
6997
+
}
6998
+
6999
+
if (target_len > 0) {
7000
+
jsval_t span_res = extend_destruct_target_span(js, p, len, target_pos, &target_len, &pos);
7001
+
if (is_err(span_res)) return span_res;
6777
7002
}
6778
7003
6779
7004
jsval_t prop_val;
6780
7005
if (is_rest && is_arr) {
6781
-
jsval_t rest = js_mkarr(js);
6782
-
if (is_err(rest)) return rest;
6783
-
jsoff_t alen = js_arr_len(js, val);
6784
-
for (jsoff_t i = idx; i < alen; i++) js_arr_push(js, rest, js_arr_get(js, val, i));
6785
-
prop_val = rest;
7006
+
prop_val = make_destruct_rest_array(js, val, idx);
7007
+
if (is_err(prop_val)) return prop_val;
6786
7008
} else if (is_rest) prop_val = mkobj(js, 0);
6787
-
else if (is_arr) prop_val = js_arr_get(js, val, idx);
7009
+
else if (is_arr) prop_val = destruct_source_get(js, val, idx);
7010
+
else if (has_computed_key) prop_val = destruct_get_by_key(js, val, computed_key);
6788
7011
else prop_val = getprop_any(js, val, &p[src_pos], src_len);
7012
+
if (is_err(prop_val)) return prop_val;
6789
7013
6790
7014
if (is_nested) {
6791
7015
jsval_t r = bind_destruct_pattern(js, &p[nested_start], nested_len, prop_val, scope);
···
6808
7032
prop_val = resolveprop(js, prop_val);
6809
7033
6810
7034
bind:;
6811
-
jsval_t vname = js_mkstr(js, &p[var_pos], var_len);
6812
-
if (is_err(vname)) return vname;
6813
-
jsval_t r = js_setprop(js, scope, vname, prop_val);
7035
+
jsval_t r;
7036
+
if (target_len > 0) r = assign_destruct_target(js, &p[target_pos], target_len, prop_val, scope);
7037
+
else {
7038
+
jsval_t vname = js_mkstr(js, &p[var_pos], var_len);
7039
+
if (is_err(vname)) return vname;
7040
+
r = js_setprop(js, scope, vname, prop_val);
7041
+
}
6814
7042
if (is_err(r)) return r;
6815
7043
6816
7044
idx++;