This repository was archived by the owner on Nov 17, 2020. It is now read-only.
forked from glix/python
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathast.c
More file actions
3384 lines (3092 loc) · 100 KB
/
ast.c
File metadata and controls
3384 lines (3092 loc) · 100 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* This file includes functions to transform a concrete syntax tree (CST) to
* an abstract syntax tree (AST). The main function is PyAST_FromNode().
*
*/
#include "Python.h"
#include "Python-ast.h"
#include "grammar.h"
#include "node.h"
#include "pyarena.h"
#include "ast.h"
#include "token.h"
#include "parsetok.h"
#include "graminit.h"
#include <assert.h>
/* Data structure used internally */
struct compiling {
char *c_encoding; /* source encoding */
PyArena *c_arena; /* arena for allocating memeory */
const char *c_filename; /* filename */
};
static asdl_seq *seq_for_testlist(struct compiling *, const node *);
static expr_ty ast_for_expr(struct compiling *, const node *);
static stmt_ty ast_for_stmt(struct compiling *, const node *);
static asdl_seq *ast_for_suite(struct compiling *, const node *);
static asdl_seq *ast_for_exprlist(struct compiling *, const node *,
expr_context_ty);
static expr_ty ast_for_testlist(struct compiling *, const node *);
static stmt_ty ast_for_classdef(struct compiling *, const node *, asdl_seq *);
/* Note different signature for ast_for_call */
static expr_ty ast_for_call(struct compiling *, const node *, expr_ty);
static PyObject *parsenumber(struct compiling *, const char *);
static PyObject *parsestr(struct compiling *, const node *n, int *bytesmode);
static PyObject *parsestrplus(struct compiling *, const node *n,
int *bytesmode);
#ifndef LINENO
#define LINENO(n) ((n)->n_lineno)
#endif
#define COMP_GENEXP 0
#define COMP_LISTCOMP 1
#define COMP_SETCOMP 2
static identifier
new_identifier(const char* n, PyArena *arena)
{
PyObject* id = PyUnicode_DecodeUTF8(n, strlen(n), NULL);
Py_UNICODE *u;
if (!id)
return NULL;
u = PyUnicode_AS_UNICODE(id);
/* Check whether there are non-ASCII characters in the
identifier; if so, normalize to NFKC. */
for (; *u; u++) {
if (*u >= 128) {
PyObject *m = PyImport_ImportModuleNoBlock("unicodedata");
PyObject *id2;
if (!m)
return NULL;
id2 = PyObject_CallMethod(m, "normalize", "sO", "NFKC", id);
Py_DECREF(m);
if (!id2)
return NULL;
Py_DECREF(id);
id = id2;
break;
}
}
PyUnicode_InternInPlace(&id);
PyArena_AddPyObject(arena, id);
return id;
}
#define NEW_IDENTIFIER(n) new_identifier(STR(n), c->c_arena)
/* This routine provides an invalid object for the syntax error.
The outermost routine must unpack this error and create the
proper object. We do this so that we don't have to pass
the filename to everything function.
XXX Maybe we should just pass the filename...
*/
static int
ast_error(const node *n, const char *errstr)
{
PyObject *u = Py_BuildValue("zi", errstr, LINENO(n));
if (!u)
return 0;
PyErr_SetObject(PyExc_SyntaxError, u);
Py_DECREF(u);
return 0;
}
static void
ast_error_finish(const char *filename)
{
PyObject *type, *value, *tback, *errstr, *loc, *tmp;
long lineno;
assert(PyErr_Occurred());
if (!PyErr_ExceptionMatches(PyExc_SyntaxError))
return;
PyErr_Fetch(&type, &value, &tback);
errstr = PyTuple_GetItem(value, 0);
if (!errstr)
return;
Py_INCREF(errstr);
lineno = PyLong_AsLong(PyTuple_GetItem(value, 1));
if (lineno == -1) {
Py_DECREF(errstr);
return;
}
Py_DECREF(value);
loc = PyErr_ProgramText(filename, lineno);
if (!loc) {
Py_INCREF(Py_None);
loc = Py_None;
}
tmp = Py_BuildValue("(zlOO)", filename, lineno, Py_None, loc);
Py_DECREF(loc);
if (!tmp) {
Py_DECREF(errstr);
return;
}
value = PyTuple_Pack(2, errstr, tmp);
Py_DECREF(errstr);
Py_DECREF(tmp);
if (!value)
return;
PyErr_Restore(type, value, tback);
}
/* num_stmts() returns number of contained statements.
Use this routine to determine how big a sequence is needed for
the statements in a parse tree. Its raison d'etre is this bit of
grammar:
stmt: simple_stmt | compound_stmt
simple_stmt: small_stmt (';' small_stmt)* [';'] NEWLINE
A simple_stmt can contain multiple small_stmt elements joined
by semicolons. If the arg is a simple_stmt, the number of
small_stmt elements is returned.
*/
static int
num_stmts(const node *n)
{
int i, l;
node *ch;
switch (TYPE(n)) {
case single_input:
if (TYPE(CHILD(n, 0)) == NEWLINE)
return 0;
else
return num_stmts(CHILD(n, 0));
case file_input:
l = 0;
for (i = 0; i < NCH(n); i++) {
ch = CHILD(n, i);
if (TYPE(ch) == stmt)
l += num_stmts(ch);
}
return l;
case stmt:
return num_stmts(CHILD(n, 0));
case compound_stmt:
return 1;
case simple_stmt:
return NCH(n) / 2; /* Divide by 2 to remove count of semi-colons */
case suite:
if (NCH(n) == 1)
return num_stmts(CHILD(n, 0));
else {
l = 0;
for (i = 2; i < (NCH(n) - 1); i++)
l += num_stmts(CHILD(n, i));
return l;
}
default: {
char buf[128];
sprintf(buf, "Non-statement found: %d %d",
TYPE(n), NCH(n));
Py_FatalError(buf);
}
}
assert(0);
return 0;
}
/* Transform the CST rooted at node * to the appropriate AST
*/
mod_ty
PyAST_FromNode(const node *n, PyCompilerFlags *flags, const char *filename,
PyArena *arena)
{
int i, j, k, num;
asdl_seq *stmts = NULL;
stmt_ty s;
node *ch;
struct compiling c;
if (flags && flags->cf_flags & PyCF_SOURCE_IS_UTF8) {
c.c_encoding = "utf-8";
if (TYPE(n) == encoding_decl) {
#if 0
ast_error(n, "encoding declaration in Unicode string");
goto error;
#endif
n = CHILD(n, 0);
}
} else if (TYPE(n) == encoding_decl) {
c.c_encoding = STR(n);
n = CHILD(n, 0);
} else {
/* PEP 3120 */
c.c_encoding = "utf-8";
}
c.c_arena = arena;
c.c_filename = filename;
k = 0;
switch (TYPE(n)) {
case file_input:
stmts = asdl_seq_new(num_stmts(n), arena);
if (!stmts)
return NULL;
for (i = 0; i < NCH(n) - 1; i++) {
ch = CHILD(n, i);
if (TYPE(ch) == NEWLINE)
continue;
REQ(ch, stmt);
num = num_stmts(ch);
if (num == 1) {
s = ast_for_stmt(&c, ch);
if (!s)
goto error;
asdl_seq_SET(stmts, k++, s);
}
else {
ch = CHILD(ch, 0);
REQ(ch, simple_stmt);
for (j = 0; j < num; j++) {
s = ast_for_stmt(&c, CHILD(ch, j * 2));
if (!s)
goto error;
asdl_seq_SET(stmts, k++, s);
}
}
}
return Module(stmts, arena);
case eval_input: {
expr_ty testlist_ast;
/* XXX Why not comp_for here? */
testlist_ast = ast_for_testlist(&c, CHILD(n, 0));
if (!testlist_ast)
goto error;
return Expression(testlist_ast, arena);
}
case single_input:
if (TYPE(CHILD(n, 0)) == NEWLINE) {
stmts = asdl_seq_new(1, arena);
if (!stmts)
goto error;
asdl_seq_SET(stmts, 0, Pass(n->n_lineno, n->n_col_offset,
arena));
if (!asdl_seq_GET(stmts, 0))
goto error;
return Interactive(stmts, arena);
}
else {
n = CHILD(n, 0);
num = num_stmts(n);
stmts = asdl_seq_new(num, arena);
if (!stmts)
goto error;
if (num == 1) {
s = ast_for_stmt(&c, n);
if (!s)
goto error;
asdl_seq_SET(stmts, 0, s);
}
else {
/* Only a simple_stmt can contain multiple statements. */
REQ(n, simple_stmt);
for (i = 0; i < NCH(n); i += 2) {
if (TYPE(CHILD(n, i)) == NEWLINE)
break;
s = ast_for_stmt(&c, CHILD(n, i));
if (!s)
goto error;
asdl_seq_SET(stmts, i / 2, s);
}
}
return Interactive(stmts, arena);
}
default:
PyErr_Format(PyExc_SystemError,
"invalid node %d for PyAST_FromNode", TYPE(n));
goto error;
}
error:
ast_error_finish(filename);
return NULL;
}
/* Return the AST repr. of the operator represented as syntax (|, ^, etc.)
*/
static operator_ty
get_operator(const node *n)
{
switch (TYPE(n)) {
case VBAR:
return BitOr;
case CIRCUMFLEX:
return BitXor;
case AMPER:
return BitAnd;
case LEFTSHIFT:
return LShift;
case RIGHTSHIFT:
return RShift;
case PLUS:
return Add;
case MINUS:
return Sub;
case STAR:
return Mult;
case SLASH:
return Div;
case DOUBLESLASH:
return FloorDiv;
case PERCENT:
return Mod;
default:
return (operator_ty)0;
}
}
static const char* FORBIDDEN[] = {
"None",
"True",
"False",
"__debug__",
NULL,
};
static int
forbidden_name(expr_ty e, const node *n)
{
const char **p;
assert(PyUnicode_Check(e->v.Name.id));
for (p = FORBIDDEN; *p; p++) {
if (PyUnicode_CompareWithASCIIString(e->v.Name.id, *p) == 0) {
ast_error(n, "assignment to keyword");
return 1;
}
}
return 0;
}
/* Set the context ctx for expr_ty e, recursively traversing e.
Only sets context for expr kinds that "can appear in assignment context"
(according to ../Parser/Python.asdl). For other expr kinds, it sets
an appropriate syntax error and returns false.
*/
static int
set_context(struct compiling *c, expr_ty e, expr_context_ty ctx, const node *n)
{
asdl_seq *s = NULL;
/* If a particular expression type can't be used for assign / delete,
set expr_name to its name and an error message will be generated.
*/
const char* expr_name = NULL;
/* The ast defines augmented store and load contexts, but the
implementation here doesn't actually use them. The code may be
a little more complex than necessary as a result. It also means
that expressions in an augmented assignment have a Store context.
Consider restructuring so that augmented assignment uses
set_context(), too.
*/
assert(ctx != AugStore && ctx != AugLoad);
switch (e->kind) {
case Attribute_kind:
e->v.Attribute.ctx = ctx;
break;
case Subscript_kind:
e->v.Subscript.ctx = ctx;
break;
case Starred_kind:
e->v.Starred.ctx = ctx;
if (!set_context(c, e->v.Starred.value, ctx, n))
return 0;
break;
case Name_kind:
if (ctx == Store) {
if (forbidden_name(e, n))
return 0; /* forbidden_name() calls ast_error() */
}
e->v.Name.ctx = ctx;
break;
case List_kind:
e->v.List.ctx = ctx;
s = e->v.List.elts;
break;
case Tuple_kind:
if (asdl_seq_LEN(e->v.Tuple.elts) == 0)
return ast_error(n, "can't assign to ()");
e->v.Tuple.ctx = ctx;
s = e->v.Tuple.elts;
break;
case Lambda_kind:
expr_name = "lambda";
break;
case Call_kind:
expr_name = "function call";
break;
case BoolOp_kind:
case BinOp_kind:
case UnaryOp_kind:
expr_name = "operator";
break;
case GeneratorExp_kind:
expr_name = "generator expression";
break;
case Yield_kind:
expr_name = "yield expression";
break;
case ListComp_kind:
expr_name = "list comprehension";
break;
case SetComp_kind:
expr_name = "set comprehension";
break;
case DictComp_kind:
expr_name = "dict comprehension";
break;
case Dict_kind:
case Set_kind:
case Num_kind:
case Str_kind:
expr_name = "literal";
break;
case Ellipsis_kind:
expr_name = "Ellipsis";
break;
case Compare_kind:
expr_name = "comparison";
break;
case IfExp_kind:
expr_name = "conditional expression";
break;
default:
PyErr_Format(PyExc_SystemError,
"unexpected expression in assignment %d (line %d)",
e->kind, e->lineno);
return 0;
}
/* Check for error string set by switch */
if (expr_name) {
char buf[300];
PyOS_snprintf(buf, sizeof(buf),
"can't %s %s",
ctx == Store ? "assign to" : "delete",
expr_name);
return ast_error(n, buf);
}
/* If the LHS is a list or tuple, we need to set the assignment
context for all the contained elements.
*/
if (s) {
int i;
for (i = 0; i < asdl_seq_LEN(s); i++) {
if (!set_context(c, (expr_ty)asdl_seq_GET(s, i), ctx, n))
return 0;
}
}
return 1;
}
static operator_ty
ast_for_augassign(struct compiling *c, const node *n)
{
REQ(n, augassign);
n = CHILD(n, 0);
switch (STR(n)[0]) {
case '+':
return Add;
case '-':
return Sub;
case '/':
if (STR(n)[1] == '/')
return FloorDiv;
else
return Div;
case '%':
return Mod;
case '<':
return LShift;
case '>':
return RShift;
case '&':
return BitAnd;
case '^':
return BitXor;
case '|':
return BitOr;
case '*':
if (STR(n)[1] == '*')
return Pow;
else
return Mult;
default:
PyErr_Format(PyExc_SystemError, "invalid augassign: %s", STR(n));
return (operator_ty)0;
}
}
static cmpop_ty
ast_for_comp_op(struct compiling *c, const node *n)
{
/* comp_op: '<'|'>'|'=='|'>='|'<='|'!='|'in'|'not' 'in'|'is'
|'is' 'not'
*/
REQ(n, comp_op);
if (NCH(n) == 1) {
n = CHILD(n, 0);
switch (TYPE(n)) {
case LESS:
return Lt;
case GREATER:
return Gt;
case EQEQUAL: /* == */
return Eq;
case LESSEQUAL:
return LtE;
case GREATEREQUAL:
return GtE;
case NOTEQUAL:
return NotEq;
case NAME:
if (strcmp(STR(n), "in") == 0)
return In;
if (strcmp(STR(n), "is") == 0)
return Is;
default:
PyErr_Format(PyExc_SystemError, "invalid comp_op: %s",
STR(n));
return (cmpop_ty)0;
}
}
else if (NCH(n) == 2) {
/* handle "not in" and "is not" */
switch (TYPE(CHILD(n, 0))) {
case NAME:
if (strcmp(STR(CHILD(n, 1)), "in") == 0)
return NotIn;
if (strcmp(STR(CHILD(n, 0)), "is") == 0)
return IsNot;
default:
PyErr_Format(PyExc_SystemError, "invalid comp_op: %s %s",
STR(CHILD(n, 0)), STR(CHILD(n, 1)));
return (cmpop_ty)0;
}
}
PyErr_Format(PyExc_SystemError, "invalid comp_op: has %d children",
NCH(n));
return (cmpop_ty)0;
}
static asdl_seq *
seq_for_testlist(struct compiling *c, const node *n)
{
/* testlist: test (',' test)* [','] */
asdl_seq *seq;
expr_ty expression;
int i;
assert(TYPE(n) == testlist || TYPE(n) == testlist_comp);
seq = asdl_seq_new((NCH(n) + 1) / 2, c->c_arena);
if (!seq)
return NULL;
for (i = 0; i < NCH(n); i += 2) {
assert(TYPE(CHILD(n, i)) == test || TYPE(CHILD(n, i)) == test_nocond);
expression = ast_for_expr(c, CHILD(n, i));
if (!expression)
return NULL;
assert(i / 2 < seq->size);
asdl_seq_SET(seq, i / 2, expression);
}
return seq;
}
static arg_ty
compiler_arg(struct compiling *c, const node *n)
{
identifier name;
expr_ty annotation = NULL;
node *ch;
assert(TYPE(n) == tfpdef || TYPE(n) == vfpdef);
ch = CHILD(n, 0);
name = NEW_IDENTIFIER(ch);
if (!name)
return NULL;
if (NCH(n) == 3 && TYPE(CHILD(n, 1)) == COLON) {
annotation = ast_for_expr(c, CHILD(n, 2));
if (!annotation)
return NULL;
}
return arg(name, annotation, c->c_arena);
#if 0
result = Tuple(args, Store, LINENO(n), n->n_col_offset, c->c_arena);
if (!set_context(c, result, Store, n))
return NULL;
return result;
#endif
}
/* returns -1 if failed to handle keyword only arguments
returns new position to keep processing if successful
(',' tfpdef ['=' test])*
^^^
start pointing here
*/
static int
handle_keywordonly_args(struct compiling *c, const node *n, int start,
asdl_seq *kwonlyargs, asdl_seq *kwdefaults)
{
PyObject *argname;
node *ch;
expr_ty expression, annotation;
arg_ty arg;
int i = start;
int j = 0; /* index for kwdefaults and kwonlyargs */
if (kwonlyargs == NULL) {
ast_error(CHILD(n, start), "named arguments must follow bare *");
return -1;
}
assert(kwdefaults != NULL);
while (i < NCH(n)) {
ch = CHILD(n, i);
switch (TYPE(ch)) {
case vfpdef:
case tfpdef:
if (i + 1 < NCH(n) && TYPE(CHILD(n, i + 1)) == EQUAL) {
expression = ast_for_expr(c, CHILD(n, i + 2));
asdl_seq_SET(kwdefaults, j, expression);
i += 2; /* '=' and test */
}
else { /* setting NULL if no default value exists */
asdl_seq_SET(kwdefaults, j, NULL);
}
if (NCH(ch) == 3) {
/* ch is NAME ':' test */
annotation = ast_for_expr(c, CHILD(ch, 2));
if (!annotation) {
ast_error(ch, "expected expression");
goto error;
}
}
else {
annotation = NULL;
}
ch = CHILD(ch, 0);
argname = NEW_IDENTIFIER(ch);
if (!argname)
goto error;
arg = arg(argname, annotation, c->c_arena);
if (!arg)
goto error;
asdl_seq_SET(kwonlyargs, j++, arg);
i += 2; /* the name and the comma */
break;
case DOUBLESTAR:
return i;
default:
ast_error(ch, "unexpected node");
goto error;
}
}
return i;
error:
return -1;
}
/* Create AST for argument list. */
static arguments_ty
ast_for_arguments(struct compiling *c, const node *n)
{
/* This function handles both typedargslist (function definition)
and varargslist (lambda definition).
parameters: '(' [typedargslist] ')'
typedargslist: ((tfpdef ['=' test] ',')*
('*' [tfpdef] (',' tfpdef ['=' test])* [',' '**' tfpdef]
| '**' tfpdef)
| tfpdef ['=' test] (',' tfpdef ['=' test])* [','])
tfpdef: NAME [':' test]
varargslist: ((vfpdef ['=' test] ',')*
('*' [vfpdef] (',' vfpdef ['=' test])* [',' '**' vfpdef]
| '**' vfpdef)
| vfpdef ['=' test] (',' vfpdef ['=' test])* [','])
vfpdef: NAME
*/
int i, j, k, nposargs = 0, nkwonlyargs = 0;
int nposdefaults = 0, found_default = 0;
asdl_seq *posargs, *posdefaults, *kwonlyargs, *kwdefaults;
identifier vararg = NULL, kwarg = NULL;
arg_ty arg;
expr_ty varargannotation = NULL, kwargannotation = NULL;
node *ch;
if (TYPE(n) == parameters) {
if (NCH(n) == 2) /* () as argument list */
return arguments(NULL, NULL, NULL, NULL, NULL, NULL, NULL,
NULL, c->c_arena);
n = CHILD(n, 1);
}
assert(TYPE(n) == typedargslist || TYPE(n) == varargslist);
/* First count the number of positional args & defaults. The
variable i is the loop index for this for loop and the next.
The next loop picks up where the first leaves off.
*/
for (i = 0; i < NCH(n); i++) {
ch = CHILD(n, i);
if (TYPE(ch) == STAR) {
/* skip star */
i++;
if (i < NCH(n) && /* skip argument following star */
(TYPE(CHILD(n, i)) == tfpdef ||
TYPE(CHILD(n, i)) == vfpdef)) {
i++;
}
break;
}
if (TYPE(ch) == DOUBLESTAR) break;
if (TYPE(ch) == vfpdef || TYPE(ch) == tfpdef) nposargs++;
if (TYPE(ch) == EQUAL) nposdefaults++;
}
/* count the number of keyword only args &
defaults for keyword only args */
for ( ; i < NCH(n); ++i) {
ch = CHILD(n, i);
if (TYPE(ch) == DOUBLESTAR) break;
if (TYPE(ch) == tfpdef || TYPE(ch) == vfpdef) nkwonlyargs++;
}
posargs = (nposargs ? asdl_seq_new(nposargs, c->c_arena) : NULL);
if (!posargs && nposargs)
goto error;
kwonlyargs = (nkwonlyargs ?
asdl_seq_new(nkwonlyargs, c->c_arena) : NULL);
if (!kwonlyargs && nkwonlyargs)
goto error;
posdefaults = (nposdefaults ?
asdl_seq_new(nposdefaults, c->c_arena) : NULL);
if (!posdefaults && nposdefaults)
goto error;
/* The length of kwonlyargs and kwdefaults are same
since we set NULL as default for keyword only argument w/o default
- we have sequence data structure, but no dictionary */
kwdefaults = (nkwonlyargs ?
asdl_seq_new(nkwonlyargs, c->c_arena) : NULL);
if (!kwdefaults && nkwonlyargs)
goto error;
if (nposargs + nkwonlyargs > 255) {
ast_error(n, "more than 255 arguments");
return NULL;
}
/* tfpdef: NAME [':' test]
vfpdef: NAME
*/
i = 0;
j = 0; /* index for defaults */
k = 0; /* index for args */
while (i < NCH(n)) {
ch = CHILD(n, i);
switch (TYPE(ch)) {
case tfpdef:
case vfpdef:
/* XXX Need to worry about checking if TYPE(CHILD(n, i+1)) is
anything other than EQUAL or a comma? */
/* XXX Should NCH(n) check be made a separate check? */
if (i + 1 < NCH(n) && TYPE(CHILD(n, i + 1)) == EQUAL) {
expr_ty expression = ast_for_expr(c, CHILD(n, i + 2));
if (!expression)
goto error;
assert(posdefaults != NULL);
asdl_seq_SET(posdefaults, j++, expression);
i += 2;
found_default = 1;
}
else if (found_default) {
ast_error(n,
"non-default argument follows default argument");
goto error;
}
arg = compiler_arg(c, ch);
if (!arg)
goto error;
asdl_seq_SET(posargs, k++, arg);
i += 2; /* the name and the comma */
break;
case STAR:
if (i+1 >= NCH(n)) {
ast_error(CHILD(n, i),
"named arguments must follow bare *");
goto error;
}
ch = CHILD(n, i+1); /* tfpdef or COMMA */
if (TYPE(ch) == COMMA) {
int res = 0;
i += 2; /* now follows keyword only arguments */
res = handle_keywordonly_args(c, n, i,
kwonlyargs, kwdefaults);
if (res == -1) goto error;
i = res; /* res has new position to process */
}
else {
vararg = NEW_IDENTIFIER(CHILD(ch, 0));
if (!vararg)
return NULL;
if (NCH(ch) > 1) {
/* there is an annotation on the vararg */
varargannotation = ast_for_expr(c, CHILD(ch, 2));
}
i += 3;
if (i < NCH(n) && (TYPE(CHILD(n, i)) == tfpdef
|| TYPE(CHILD(n, i)) == vfpdef)) {
int res = 0;
res = handle_keywordonly_args(c, n, i,
kwonlyargs, kwdefaults);
if (res == -1) goto error;
i = res; /* res has new position to process */
}
}
break;
case DOUBLESTAR:
ch = CHILD(n, i+1); /* tfpdef */
assert(TYPE(ch) == tfpdef || TYPE(ch) == vfpdef);
kwarg = NEW_IDENTIFIER(CHILD(ch, 0));
if (NCH(ch) > 1) {
/* there is an annotation on the kwarg */
kwargannotation = ast_for_expr(c, CHILD(ch, 2));
}
if (!kwarg)
goto error;
i += 3;
break;
default:
PyErr_Format(PyExc_SystemError,
"unexpected node in varargslist: %d @ %d",
TYPE(ch), i);
goto error;
}
}
return arguments(posargs, vararg, varargannotation, kwonlyargs, kwarg,
kwargannotation, posdefaults, kwdefaults, c->c_arena);
error:
Py_XDECREF(vararg);
Py_XDECREF(kwarg);
return NULL;
}
static expr_ty
ast_for_dotted_name(struct compiling *c, const node *n)
{
expr_ty e;
identifier id;
int lineno, col_offset;
int i;
REQ(n, dotted_name);
lineno = LINENO(n);
col_offset = n->n_col_offset;
id = NEW_IDENTIFIER(CHILD(n, 0));
if (!id)
return NULL;
e = Name(id, Load, lineno, col_offset, c->c_arena);
if (!e)
return NULL;
for (i = 2; i < NCH(n); i+=2) {
id = NEW_IDENTIFIER(CHILD(n, i));
if (!id)
return NULL;
e = Attribute(e, id, Load, lineno, col_offset, c->c_arena);
if (!e)
return NULL;
}
return e;
}
static expr_ty
ast_for_decorator(struct compiling *c, const node *n)
{
/* decorator: '@' dotted_name [ '(' [arglist] ')' ] NEWLINE */
expr_ty d = NULL;
expr_ty name_expr;
REQ(n, decorator);
REQ(CHILD(n, 0), AT);
REQ(RCHILD(n, -1), NEWLINE);
name_expr = ast_for_dotted_name(c, CHILD(n, 1));
if (!name_expr)
return NULL;
if (NCH(n) == 3) { /* No arguments */
d = name_expr;
name_expr = NULL;
}
else if (NCH(n) == 5) { /* Call with no arguments */
d = Call(name_expr, NULL, NULL, NULL, NULL, LINENO(n),
n->n_col_offset, c->c_arena);
if (!d)
return NULL;
name_expr = NULL;
}
else {
d = ast_for_call(c, CHILD(n, 3), name_expr);
if (!d)
return NULL;
name_expr = NULL;
}
return d;
}
static asdl_seq*
ast_for_decorators(struct compiling *c, const node *n)
{
asdl_seq* decorator_seq;
expr_ty d;
int i;
REQ(n, decorators);
decorator_seq = asdl_seq_new(NCH(n), c->c_arena);
if (!decorator_seq)
return NULL;
for (i = 0; i < NCH(n); i++) {
d = ast_for_decorator(c, CHILD(n, i));
if (!d)
return NULL;
asdl_seq_SET(decorator_seq, i, d);
}
return decorator_seq;
}
static stmt_ty
ast_for_funcdef(struct compiling *c, const node *n, asdl_seq *decorator_seq)
{
/* funcdef: 'def' NAME parameters ['->' test] ':' suite */
identifier name;
arguments_ty args;
asdl_seq *body;
expr_ty returns = NULL;
int name_i = 1;
REQ(n, funcdef);
name = NEW_IDENTIFIER(CHILD(n, name_i));
if (!name)
return NULL;