xref: /vim-8.2.3635/src/vim9type.c (revision bf5f2878)
1 /* vi:set ts=8 sts=4 sw=4 noet:
2  *
3  * VIM - Vi IMproved	by Bram Moolenaar
4  *
5  * Do ":help uganda"  in Vim to read copying and usage conditions.
6  * Do ":help credits" in Vim to see a list of people who contributed.
7  * See README.txt for an overview of the Vim source code.
8  */
9 
10 /*
11  * vim9type.c: handling of types
12  */
13 
14 #define USING_FLOAT_STUFF
15 #include "vim.h"
16 
17 #if defined(FEAT_EVAL) || defined(PROTO)
18 
19 #ifdef VMS
20 # include <float.h>
21 #endif
22 
23 /*
24  * Allocate memory for a type_T and add the pointer to type_gap, so that it can
25  * be easily freed later.
26  */
27     static type_T *
28 get_type_ptr(garray_T *type_gap)
29 {
30     type_T *type;
31 
32     if (ga_grow(type_gap, 1) == FAIL)
33 	return NULL;
34     type = ALLOC_CLEAR_ONE(type_T);
35     if (type != NULL)
36     {
37 	((type_T **)type_gap->ga_data)[type_gap->ga_len] = type;
38 	++type_gap->ga_len;
39     }
40     return type;
41 }
42 
43     void
44 clear_type_list(garray_T *gap)
45 {
46     while (gap->ga_len > 0)
47 	vim_free(((type_T **)gap->ga_data)[--gap->ga_len]);
48     ga_clear(gap);
49 }
50 
51 /*
52  * Take a type that is using entries in a growarray and turn it into a type
53  * with allocated entries.
54  */
55     type_T *
56 alloc_type(type_T *type)
57 {
58     type_T *ret;
59 
60     if (type == NULL)
61 	return NULL;
62 
63     // A fixed type never contains allocated types, return as-is.
64     if (type->tt_flags & TTFLAG_STATIC)
65 	return type;
66 
67     ret = ALLOC_ONE(type_T);
68     *ret = *type;
69 
70     if (ret->tt_member != NULL)
71 	ret->tt_member = alloc_type(ret->tt_member);
72     if (type->tt_args != NULL)
73     {
74 	int i;
75 
76 	ret->tt_args = ALLOC_MULT(type_T *, type->tt_argcount);
77 	if (ret->tt_args != NULL)
78 	    for (i = 0; i < type->tt_argcount; ++i)
79 		ret->tt_args[i] = alloc_type(type->tt_args[i]);
80     }
81 
82     return ret;
83 }
84 
85 /*
86  * Free a type that was created with alloc_type().
87  */
88     void
89 free_type(type_T *type)
90 {
91     int i;
92 
93     if (type == NULL || (type->tt_flags & TTFLAG_STATIC))
94 	return;
95     if (type->tt_args != NULL)
96     {
97 	for (i = 0; i < type->tt_argcount; ++i)
98 	    free_type(type->tt_args[i]);
99 	vim_free(type->tt_args);
100     }
101     free_type(type->tt_member);
102     vim_free(type);
103 }
104 
105     type_T *
106 get_list_type(type_T *member_type, garray_T *type_gap)
107 {
108     type_T *type;
109 
110     // recognize commonly used types
111     if (member_type == NULL || member_type->tt_type == VAR_ANY)
112 	return &t_list_any;
113     if (member_type->tt_type == VAR_VOID
114 	    || member_type->tt_type == VAR_UNKNOWN)
115 	return &t_list_empty;
116     if (member_type->tt_type == VAR_BOOL)
117 	return &t_list_bool;
118     if (member_type->tt_type == VAR_NUMBER)
119 	return &t_list_number;
120     if (member_type->tt_type == VAR_STRING)
121 	return &t_list_string;
122 
123     // Not a common type, create a new entry.
124     type = get_type_ptr(type_gap);
125     if (type == NULL)
126 	return &t_any;
127     type->tt_type = VAR_LIST;
128     type->tt_member = member_type;
129     type->tt_argcount = 0;
130     type->tt_args = NULL;
131     return type;
132 }
133 
134     type_T *
135 get_dict_type(type_T *member_type, garray_T *type_gap)
136 {
137     type_T *type;
138 
139     // recognize commonly used types
140     if (member_type == NULL || member_type->tt_type == VAR_ANY)
141 	return &t_dict_any;
142     if (member_type->tt_type == VAR_VOID
143 	    || member_type->tt_type == VAR_UNKNOWN)
144 	return &t_dict_empty;
145     if (member_type->tt_type == VAR_BOOL)
146 	return &t_dict_bool;
147     if (member_type->tt_type == VAR_NUMBER)
148 	return &t_dict_number;
149     if (member_type->tt_type == VAR_STRING)
150 	return &t_dict_string;
151 
152     // Not a common type, create a new entry.
153     type = get_type_ptr(type_gap);
154     if (type == NULL)
155 	return &t_any;
156     type->tt_type = VAR_DICT;
157     type->tt_member = member_type;
158     type->tt_argcount = 0;
159     type->tt_args = NULL;
160     return type;
161 }
162 
163 /*
164  * Allocate a new type for a function.
165  */
166     type_T *
167 alloc_func_type(type_T *ret_type, int argcount, garray_T *type_gap)
168 {
169     type_T *type = get_type_ptr(type_gap);
170 
171     if (type == NULL)
172 	return &t_any;
173     type->tt_type = VAR_FUNC;
174     type->tt_member = ret_type == NULL ? &t_unknown : ret_type;
175     type->tt_argcount = argcount;
176     type->tt_args = NULL;
177     return type;
178 }
179 
180 /*
181  * Get a function type, based on the return type "ret_type".
182  * If "argcount" is -1 or 0 a predefined type can be used.
183  * If "argcount" > 0 always create a new type, so that arguments can be added.
184  */
185     type_T *
186 get_func_type(type_T *ret_type, int argcount, garray_T *type_gap)
187 {
188     // recognize commonly used types
189     if (argcount <= 0)
190     {
191 	if (ret_type == &t_unknown || ret_type == NULL)
192 	{
193 	    // (argcount == 0) is not possible
194 	    return &t_func_unknown;
195 	}
196 	if (ret_type == &t_void)
197 	{
198 	    if (argcount == 0)
199 		return &t_func_0_void;
200 	    else
201 		return &t_func_void;
202 	}
203 	if (ret_type == &t_any)
204 	{
205 	    if (argcount == 0)
206 		return &t_func_0_any;
207 	    else
208 		return &t_func_any;
209 	}
210 	if (ret_type == &t_number)
211 	{
212 	    if (argcount == 0)
213 		return &t_func_0_number;
214 	    else
215 		return &t_func_number;
216 	}
217 	if (ret_type == &t_string)
218 	{
219 	    if (argcount == 0)
220 		return &t_func_0_string;
221 	    else
222 		return &t_func_string;
223 	}
224     }
225 
226     return alloc_func_type(ret_type, argcount, type_gap);
227 }
228 
229 /*
230  * For a function type, reserve space for "argcount" argument types (including
231  * vararg).
232  */
233     int
234 func_type_add_arg_types(
235 	type_T	    *functype,
236 	int	    argcount,
237 	garray_T    *type_gap)
238 {
239     // To make it easy to free the space needed for the argument types, add the
240     // pointer to type_gap.
241     if (ga_grow(type_gap, 1) == FAIL)
242 	return FAIL;
243     functype->tt_args = ALLOC_CLEAR_MULT(type_T *, argcount);
244     if (functype->tt_args == NULL)
245 	return FAIL;
246     ((type_T **)type_gap->ga_data)[type_gap->ga_len] =
247 						     (void *)functype->tt_args;
248     ++type_gap->ga_len;
249     return OK;
250 }
251 
252 /*
253  * Get a type_T for a typval_T.
254  * "type_gap" is used to temporarily create types in.
255  * When "do_member" is TRUE also get the member type, otherwise use "any".
256  */
257     static type_T *
258 typval2type_int(typval_T *tv, int copyID, garray_T *type_gap, int do_member)
259 {
260     type_T  *type;
261     type_T  *member_type = &t_any;
262     int	    argcount = 0;
263     int	    min_argcount = 0;
264 
265     if (tv->v_type == VAR_NUMBER)
266 	return &t_number;
267     if (tv->v_type == VAR_BOOL)
268 	return &t_bool;
269     if (tv->v_type == VAR_STRING)
270 	return &t_string;
271 
272     if (tv->v_type == VAR_LIST)
273     {
274 	list_T	    *l = tv->vval.v_list;
275 	listitem_T  *li;
276 
277 	if (l == NULL || (l->lv_first == NULL && l->lv_type == NULL))
278 	    return &t_list_empty;
279 	if (!do_member)
280 	    return &t_list_any;
281 	if (l->lv_type != NULL)
282 	    return l->lv_type;
283 	if (l->lv_first == &range_list_item)
284 	    return &t_list_number;
285 	if (l->lv_copyID == copyID)
286 	    // avoid recursion
287 	    return &t_list_any;
288 	l->lv_copyID = copyID;
289 
290 	// Use the common type of all members.
291 	member_type = typval2type(&l->lv_first->li_tv, copyID, type_gap, TRUE);
292 	for (li = l->lv_first->li_next; li != NULL; li = li->li_next)
293 	    common_type(typval2type(&li->li_tv, copyID, type_gap, TRUE),
294 					  member_type, &member_type, type_gap);
295 	return get_list_type(member_type, type_gap);
296     }
297 
298     if (tv->v_type == VAR_DICT)
299     {
300 	dict_iterator_T iter;
301 	typval_T	*value;
302 	dict_T		*d = tv->vval.v_dict;
303 
304 	if (d == NULL || (d->dv_hashtab.ht_used == 0 && d->dv_type == NULL))
305 	    return &t_dict_empty;
306 	if (!do_member)
307 	    return &t_dict_any;
308 	if (d->dv_type != NULL)
309 	    return d->dv_type;
310 	if (d->dv_copyID == copyID)
311 	    // avoid recursion
312 	    return &t_dict_any;
313 	d->dv_copyID = copyID;
314 
315 	// Use the common type of all values.
316 	dict_iterate_start(tv, &iter);
317 	dict_iterate_next(&iter, &value);
318 	member_type = typval2type(value, copyID, type_gap, TRUE);
319 	while (dict_iterate_next(&iter, &value) != NULL)
320 	    common_type(typval2type(value, copyID, type_gap, TRUE),
321 					  member_type, &member_type, type_gap);
322 	return get_dict_type(member_type, type_gap);
323     }
324 
325     if (tv->v_type == VAR_FUNC || tv->v_type == VAR_PARTIAL)
326     {
327 	char_u	*name = NULL;
328 	ufunc_T *ufunc = NULL;
329 
330 	if (tv->v_type == VAR_PARTIAL)
331 	{
332 	    if (tv->vval.v_partial->pt_func != NULL)
333 		ufunc = tv->vval.v_partial->pt_func;
334 	    else
335 		name = tv->vval.v_partial->pt_name;
336 	}
337 	else
338 	    name = tv->vval.v_string;
339 	if (name != NULL)
340 	{
341 	    int idx = find_internal_func(name);
342 
343 	    if (idx >= 0)
344 	    {
345 		internal_func_get_argcount(idx, &argcount, &min_argcount);
346 		member_type = internal_func_ret_type(idx, 0, NULL);
347 	    }
348 	    else
349 		ufunc = find_func(name, FALSE, NULL);
350 	}
351 	if (ufunc != NULL)
352 	{
353 	    // May need to get the argument types from default values by
354 	    // compiling the function.
355 	    if (ufunc->uf_def_status == UF_TO_BE_COMPILED
356 			    && compile_def_function(ufunc, TRUE, CT_NONE, NULL)
357 								       == FAIL)
358 		return NULL;
359 	    if (ufunc->uf_func_type == NULL)
360 		set_function_type(ufunc);
361 	    if (ufunc->uf_func_type != NULL)
362 	    {
363 		if (tv->v_type == VAR_PARTIAL
364 					    && tv->vval.v_partial->pt_argc > 0)
365 		{
366 		    type = get_type_ptr(type_gap);
367 		    if (type == NULL)
368 			return NULL;
369 		    *type = *ufunc->uf_func_type;
370 		    type->tt_argcount -= tv->vval.v_partial->pt_argc;
371 		    type->tt_min_argcount -= tv->vval.v_partial->pt_argc;
372 		    return type;
373 		}
374 		return ufunc->uf_func_type;
375 	    }
376 	}
377     }
378 
379     type = get_type_ptr(type_gap);
380     if (type == NULL)
381 	return NULL;
382     type->tt_type = tv->v_type;
383     type->tt_argcount = argcount;
384     type->tt_min_argcount = min_argcount;
385     if (tv->v_type == VAR_PARTIAL && tv->vval.v_partial->pt_argc > 0)
386     {
387 	type->tt_argcount -= tv->vval.v_partial->pt_argc;
388 	type->tt_min_argcount -= tv->vval.v_partial->pt_argc;
389     }
390     type->tt_member = member_type;
391 
392     return type;
393 }
394 
395 /*
396  * Return TRUE if "tv" is not a bool but should be converted to bool.
397  */
398     int
399 need_convert_to_bool(type_T *type, typval_T *tv)
400 {
401     return type != NULL && type == &t_bool && tv->v_type != VAR_BOOL
402 	    && (tv->v_type == VAR_NUMBER
403 		       && (tv->vval.v_number == 0 || tv->vval.v_number == 1));
404 }
405 
406 /*
407  * Get a type_T for a typval_T.
408  * "type_list" is used to temporarily create types in.
409  * When "do_member" is TRUE also get the member type, otherwise use "any".
410  */
411     type_T *
412 typval2type(typval_T *tv, int copyID, garray_T *type_gap, int do_member)
413 {
414     type_T *type = typval2type_int(tv, copyID, type_gap, do_member);
415 
416     if (type != NULL && type != &t_bool
417 	    && (tv->v_type == VAR_NUMBER
418 		    && (tv->vval.v_number == 0 || tv->vval.v_number == 1)))
419 	// Number 0 and 1 and expression with "&&" or "||" can also be used for
420 	// bool.
421 	type = &t_number_bool;
422     return type;
423 }
424 
425 /*
426  * Get a type_T for a typval_T, used for v: variables.
427  * "type_list" is used to temporarily create types in.
428  */
429     type_T *
430 typval2type_vimvar(typval_T *tv, garray_T *type_gap)
431 {
432     if (tv->v_type == VAR_LIST)  // e.g. for v:oldfiles
433 	return &t_list_string;
434     if (tv->v_type == VAR_DICT)  // e.g. for v:completed_item
435 	return &t_dict_any;
436     return typval2type(tv, get_copyID(), type_gap, TRUE);
437 }
438 
439     int
440 check_typval_arg_type(
441 	type_T	    *expected,
442 	typval_T    *actual_tv,
443 	char	    *func_name,
444 	int	    arg_idx)
445 {
446     where_T	where = WHERE_INIT;
447 
448     where.wt_index = arg_idx;
449     where.wt_func_name = func_name;
450     return check_typval_type(expected, actual_tv, where);
451 }
452 
453 /*
454  * Return FAIL if "expected" and "actual" don't match.
455  * When "argidx" > 0 it is included in the error message.
456  */
457     int
458 check_typval_type(type_T *expected, typval_T *actual_tv, where_T where)
459 {
460     garray_T	type_list;
461     type_T	*actual_type;
462     int		res = FAIL;
463 
464     // For some values there is no type, assume an error will be given later
465     // for an invalid value.
466     if ((actual_tv->v_type == VAR_FUNC && actual_tv->vval.v_string == NULL)
467 	    || (actual_tv->v_type == VAR_PARTIAL
468 					 && actual_tv->vval.v_partial == NULL))
469     {
470 	emsg(_(e_function_reference_is_not_set));
471 	return FAIL;
472     }
473 
474     ga_init2(&type_list, sizeof(type_T *), 10);
475     actual_type = typval2type(actual_tv, get_copyID(), &type_list, TRUE);
476     if (actual_type != NULL)
477 	res = check_type(expected, actual_type, TRUE, where);
478     clear_type_list(&type_list);
479     return res;
480 }
481 
482     void
483 type_mismatch(type_T *expected, type_T *actual)
484 {
485     arg_type_mismatch(expected, actual, 0);
486 }
487 
488     void
489 arg_type_mismatch(type_T *expected, type_T *actual, int arg_idx)
490 {
491     where_T	where = WHERE_INIT;
492 
493     where.wt_index = arg_idx;
494     type_mismatch_where(expected, actual, where);
495 }
496 
497     void
498 type_mismatch_where(type_T *expected, type_T *actual, where_T where)
499 {
500     char *tofree1, *tofree2;
501     char *typename1 = type_name(expected, &tofree1);
502     char *typename2 = type_name(actual, &tofree2);
503 
504     if (where.wt_index > 0)
505     {
506 	if (where.wt_func_name == NULL)
507 	    semsg(_(where.wt_variable
508 			 ? e_variable_nr_type_mismatch_expected_str_but_got_str
509 		       : e_argument_nr_type_mismatch_expected_str_but_got_str),
510 					 where.wt_index, typename1, typename2);
511 	else
512 	    semsg(_(where.wt_variable
513 		  ? e_variable_nr_type_mismatch_expected_str_but_got_str_in_str
514 		: e_argument_nr_type_mismatch_expected_str_but_got_str_in_str),
515 		     where.wt_index, typename1, typename2, where.wt_func_name);
516     }
517     else if (where.wt_func_name == NULL)
518 	semsg(_(e_type_mismatch_expected_str_but_got_str),
519 							 typename1, typename2);
520     else
521 	semsg(_(e_type_mismatch_expected_str_but_got_str_in_str),
522 				     typename1, typename2, where.wt_func_name);
523     vim_free(tofree1);
524     vim_free(tofree2);
525 }
526 
527 /*
528  * Check if the expected and actual types match.
529  * Does not allow for assigning "any" to a specific type.
530  * When "argidx" > 0 it is included in the error message.
531  */
532     int
533 check_type(type_T *expected, type_T *actual, int give_msg, where_T where)
534 {
535     int ret = OK;
536 
537     // When expected is "unknown" we accept any actual type.
538     // When expected is "any" we accept any actual type except "void".
539     if (expected->tt_type != VAR_UNKNOWN
540 	    && !(expected->tt_type == VAR_ANY && actual->tt_type != VAR_VOID))
541 
542     {
543 	// tt_type should match, except that a "partial" can be assigned to a
544 	// variable with type "func".
545 	if (!(expected->tt_type == actual->tt_type
546 		    || (expected->tt_type == VAR_FUNC
547 					   && actual->tt_type == VAR_PARTIAL)))
548 	{
549 	    if (expected->tt_type == VAR_BOOL
550 					&& (actual->tt_flags & TTFLAG_BOOL_OK))
551 		// Using number 0 or 1 for bool is OK.
552 		return OK;
553 	    if (give_msg)
554 		type_mismatch_where(expected, actual, where);
555 	    return FAIL;
556 	}
557 	if (expected->tt_type == VAR_DICT || expected->tt_type == VAR_LIST)
558 	{
559 	    // "unknown" is used for an empty list or dict
560 	    if (actual->tt_member != &t_unknown)
561 		ret = check_type(expected->tt_member, actual->tt_member,
562 								 FALSE, where);
563 	}
564 	else if (expected->tt_type == VAR_FUNC)
565 	{
566 	    // If the return type is unknown it can be anything, including
567 	    // nothing, thus there is no point in checking.
568 	    if (expected->tt_member != &t_unknown
569 					    && actual->tt_member != &t_unknown)
570 		ret = check_type(expected->tt_member, actual->tt_member,
571 								 FALSE, where);
572 	    if (ret == OK && expected->tt_argcount != -1
573 		    && actual->tt_min_argcount != -1
574 		    && (actual->tt_argcount == -1
575 			|| (actual->tt_argcount < expected->tt_min_argcount
576 			    || actual->tt_argcount > expected->tt_argcount)))
577 		ret = FAIL;
578 	    if (ret == OK && expected->tt_args != NULL
579 						    && actual->tt_args != NULL)
580 	    {
581 		int i;
582 
583 		for (i = 0; i < expected->tt_argcount; ++i)
584 		    // Allow for using "any" argument type, lambda's have them.
585 		    if (actual->tt_args[i] != &t_any && check_type(
586 			    expected->tt_args[i], actual->tt_args[i], FALSE,
587 								where) == FAIL)
588 		    {
589 			ret = FAIL;
590 			break;
591 		    }
592 	    }
593 	}
594 	if (ret == FAIL && give_msg)
595 	    type_mismatch_where(expected, actual, where);
596     }
597     return ret;
598 }
599 
600 /*
601  * Check that the arguments of "type" match "argvars[argcount]".
602  * Return OK/FAIL.
603  */
604     int
605 check_argument_types(
606 	type_T	    *type,
607 	typval_T    *argvars,
608 	int	    argcount,
609 	char_u	    *name)
610 {
611     int	    varargs = (type->tt_flags & TTFLAG_VARARGS) ? 1 : 0;
612     int	    i;
613 
614     if (type->tt_type != VAR_FUNC && type->tt_type != VAR_PARTIAL)
615 	return OK;  // just in case
616     if (argcount < type->tt_min_argcount - varargs)
617     {
618 	semsg(_(e_toofewarg), name);
619 	return FAIL;
620     }
621     if (!varargs && type->tt_argcount >= 0 && argcount > type->tt_argcount)
622     {
623 	semsg(_(e_toomanyarg), name);
624 	return FAIL;
625     }
626     if (type->tt_args == NULL)
627 	return OK;  // cannot check
628 
629 
630     for (i = 0; i < argcount; ++i)
631     {
632 	type_T	*expected;
633 
634 	if (varargs && i >= type->tt_argcount - 1)
635 	    expected = type->tt_args[type->tt_argcount - 1]->tt_member;
636 	else
637 	    expected = type->tt_args[i];
638 	if (check_typval_arg_type(expected, &argvars[i], NULL, i + 1) == FAIL)
639 	    return FAIL;
640     }
641     return OK;
642 }
643 
644 /*
645  * Skip over a type definition and return a pointer to just after it.
646  * When "optional" is TRUE then a leading "?" is accepted.
647  */
648     char_u *
649 skip_type(char_u *start, int optional)
650 {
651     char_u *p = start;
652 
653     if (optional && *p == '?')
654 	++p;
655     while (ASCII_ISALNUM(*p) || *p == '_')
656 	++p;
657 
658     // Skip over "<type>"; this is permissive about white space.
659     if (*skipwhite(p) == '<')
660     {
661 	p = skipwhite(p);
662 	p = skip_type(skipwhite(p + 1), FALSE);
663 	p = skipwhite(p);
664 	if (*p == '>')
665 	    ++p;
666     }
667     else if ((*p == '(' || (*p == ':' && VIM_ISWHITE(p[1])))
668 					     && STRNCMP("func", start, 4) == 0)
669     {
670 	if (*p == '(')
671 	{
672 	    // handle func(args): type
673 	    ++p;
674 	    while (*p != ')' && *p != NUL)
675 	    {
676 		char_u *sp = p;
677 
678 		if (STRNCMP(p, "...", 3) == 0)
679 		    p += 3;
680 		p = skip_type(p, TRUE);
681 		if (p == sp)
682 		    return p;  // syntax error
683 		if (*p == ',')
684 		    p = skipwhite(p + 1);
685 	    }
686 	    if (*p == ')')
687 	    {
688 		if (p[1] == ':')
689 		    p = skip_type(skipwhite(p + 2), FALSE);
690 		else
691 		    ++p;
692 	    }
693 	}
694 	else
695 	{
696 	    // handle func: return_type
697 	    p = skip_type(skipwhite(p + 1), FALSE);
698 	}
699     }
700 
701     return p;
702 }
703 
704 /*
705  * Parse the member type: "<type>" and return "type" with the member set.
706  * Use "type_gap" if a new type needs to be added.
707  * Returns NULL in case of failure.
708  */
709     static type_T *
710 parse_type_member(
711 	char_u	    **arg,
712 	type_T	    *type,
713 	garray_T    *type_gap,
714 	int	    give_error)
715 {
716     type_T  *member_type;
717     int	    prev_called_emsg = called_emsg;
718 
719     if (**arg != '<')
720     {
721 	if (give_error)
722 	{
723 	    if (*skipwhite(*arg) == '<')
724 		semsg(_(e_no_white_space_allowed_before_str_str), "<", *arg);
725 	    else
726 		emsg(_(e_missing_type));
727 	}
728 	return NULL;
729     }
730     *arg = skipwhite(*arg + 1);
731 
732     member_type = parse_type(arg, type_gap, give_error);
733     if (member_type == NULL)
734 	return NULL;
735 
736     *arg = skipwhite(*arg);
737     if (**arg != '>' && called_emsg == prev_called_emsg)
738     {
739 	if (give_error)
740 	    emsg(_(e_missing_gt_after_type));
741 	return NULL;
742     }
743     ++*arg;
744 
745     if (type->tt_type == VAR_LIST)
746 	return get_list_type(member_type, type_gap);
747     return get_dict_type(member_type, type_gap);
748 }
749 
750 /*
751  * Parse a type at "arg" and advance over it.
752  * When "give_error" is TRUE give error messages, otherwise be quiet.
753  * Return NULL for failure.
754  */
755     type_T *
756 parse_type(char_u **arg, garray_T *type_gap, int give_error)
757 {
758     char_u  *p = *arg;
759     size_t  len;
760 
761     // skip over the first word
762     while (ASCII_ISALNUM(*p) || *p == '_')
763 	++p;
764     len = p - *arg;
765 
766     switch (**arg)
767     {
768 	case 'a':
769 	    if (len == 3 && STRNCMP(*arg, "any", len) == 0)
770 	    {
771 		*arg += len;
772 		return &t_any;
773 	    }
774 	    break;
775 	case 'b':
776 	    if (len == 4 && STRNCMP(*arg, "bool", len) == 0)
777 	    {
778 		*arg += len;
779 		return &t_bool;
780 	    }
781 	    if (len == 4 && STRNCMP(*arg, "blob", len) == 0)
782 	    {
783 		*arg += len;
784 		return &t_blob;
785 	    }
786 	    break;
787 	case 'c':
788 	    if (len == 7 && STRNCMP(*arg, "channel", len) == 0)
789 	    {
790 		*arg += len;
791 		return &t_channel;
792 	    }
793 	    break;
794 	case 'd':
795 	    if (len == 4 && STRNCMP(*arg, "dict", len) == 0)
796 	    {
797 		*arg += len;
798 		return parse_type_member(arg, &t_dict_any,
799 							 type_gap, give_error);
800 	    }
801 	    break;
802 	case 'f':
803 	    if (len == 5 && STRNCMP(*arg, "float", len) == 0)
804 	    {
805 #ifdef FEAT_FLOAT
806 		*arg += len;
807 		return &t_float;
808 #else
809 		if (give_error)
810 		    emsg(_(e_this_vim_is_not_compiled_with_float_support));
811 		return NULL;
812 #endif
813 	    }
814 	    if (len == 4 && STRNCMP(*arg, "func", len) == 0)
815 	    {
816 		type_T  *type;
817 		type_T  *ret_type = &t_unknown;
818 		int	argcount = -1;
819 		int	flags = 0;
820 		int	first_optional = -1;
821 		type_T	*arg_type[MAX_FUNC_ARGS + 1];
822 
823 		// func({type}, ...{type}): {type}
824 		*arg += len;
825 		if (**arg == '(')
826 		{
827 		    // "func" may or may not return a value, "func()" does
828 		    // not return a value.
829 		    ret_type = &t_void;
830 
831 		    p = ++*arg;
832 		    argcount = 0;
833 		    while (*p != NUL && *p != ')')
834 		    {
835 			if (*p == '?')
836 			{
837 			    if (first_optional == -1)
838 				first_optional = argcount;
839 			    ++p;
840 			}
841 			else if (STRNCMP(p, "...", 3) == 0)
842 			{
843 			    flags |= TTFLAG_VARARGS;
844 			    p += 3;
845 			}
846 			else if (first_optional != -1)
847 			{
848 			    if (give_error)
849 				emsg(_(e_mandatory_argument_after_optional_argument));
850 			    return NULL;
851 			}
852 
853 			type = parse_type(&p, type_gap, give_error);
854 			if (type == NULL)
855 			    return NULL;
856 			arg_type[argcount++] = type;
857 
858 			// Nothing comes after "...{type}".
859 			if (flags & TTFLAG_VARARGS)
860 			    break;
861 
862 			if (*p != ',' && *skipwhite(p) == ',')
863 			{
864 			    if (give_error)
865 				semsg(_(e_no_white_space_allowed_before_str_str),
866 								       ",", p);
867 			    return NULL;
868 			}
869 			if (*p == ',')
870 			{
871 			    ++p;
872 			    if (!VIM_ISWHITE(*p))
873 			    {
874 				if (give_error)
875 				    semsg(_(e_white_space_required_after_str_str),
876 								   ",", p - 1);
877 				return NULL;
878 			    }
879 			}
880 			p = skipwhite(p);
881 			if (argcount == MAX_FUNC_ARGS)
882 			{
883 			    if (give_error)
884 				emsg(_(e_too_many_argument_types));
885 			    return NULL;
886 			}
887 		    }
888 
889 		    p = skipwhite(p);
890 		    if (*p != ')')
891 		    {
892 			if (give_error)
893 			    emsg(_(e_missing_close));
894 			return NULL;
895 		    }
896 		    *arg = p + 1;
897 		}
898 		if (**arg == ':')
899 		{
900 		    // parse return type
901 		    ++*arg;
902 		    if (!VIM_ISWHITE(**arg) && give_error)
903 			semsg(_(e_white_space_required_after_str_str),
904 								":", *arg - 1);
905 		    *arg = skipwhite(*arg);
906 		    ret_type = parse_type(arg, type_gap, give_error);
907 		    if (ret_type == NULL)
908 			return NULL;
909 		}
910 		if (flags == 0 && first_optional == -1 && argcount <= 0)
911 		    type = get_func_type(ret_type, argcount, type_gap);
912 		else
913 		{
914 		    type = alloc_func_type(ret_type, argcount, type_gap);
915 		    type->tt_flags = flags;
916 		    if (argcount > 0)
917 		    {
918 			type->tt_argcount = argcount;
919 			type->tt_min_argcount = first_optional == -1
920 						   ? argcount : first_optional;
921 			if (func_type_add_arg_types(type, argcount,
922 							     type_gap) == FAIL)
923 			    return NULL;
924 			mch_memmove(type->tt_args, arg_type,
925 						  sizeof(type_T *) * argcount);
926 		    }
927 		}
928 		return type;
929 	    }
930 	    break;
931 	case 'j':
932 	    if (len == 3 && STRNCMP(*arg, "job", len) == 0)
933 	    {
934 		*arg += len;
935 		return &t_job;
936 	    }
937 	    break;
938 	case 'l':
939 	    if (len == 4 && STRNCMP(*arg, "list", len) == 0)
940 	    {
941 		*arg += len;
942 		return parse_type_member(arg, &t_list_any,
943 							 type_gap, give_error);
944 	    }
945 	    break;
946 	case 'n':
947 	    if (len == 6 && STRNCMP(*arg, "number", len) == 0)
948 	    {
949 		*arg += len;
950 		return &t_number;
951 	    }
952 	    break;
953 	case 's':
954 	    if (len == 6 && STRNCMP(*arg, "string", len) == 0)
955 	    {
956 		*arg += len;
957 		return &t_string;
958 	    }
959 	    break;
960 	case 'v':
961 	    if (len == 4 && STRNCMP(*arg, "void", len) == 0)
962 	    {
963 		*arg += len;
964 		return &t_void;
965 	    }
966 	    break;
967     }
968 
969     if (give_error)
970 	semsg(_(e_type_not_recognized_str), *arg);
971     return NULL;
972 }
973 
974 /*
975  * Check if "type1" and "type2" are exactly the same.
976  * "flags" can have ETYPE_ARG_UNKNOWN, which means that an unknown argument
977  * type in "type1" is accepted.
978  */
979     int
980 equal_type(type_T *type1, type_T *type2, int flags)
981 {
982     int i;
983 
984     if (type1 == NULL || type2 == NULL)
985 	return FALSE;
986     if (type1->tt_type != type2->tt_type)
987 	return FALSE;
988     switch (type1->tt_type)
989     {
990 	case VAR_UNKNOWN:
991 	case VAR_ANY:
992 	case VAR_VOID:
993 	case VAR_SPECIAL:
994 	case VAR_BOOL:
995 	case VAR_NUMBER:
996 	case VAR_FLOAT:
997 	case VAR_STRING:
998 	case VAR_BLOB:
999 	case VAR_JOB:
1000 	case VAR_CHANNEL:
1001 	case VAR_INSTR:
1002 	    break;  // not composite is always OK
1003 	case VAR_LIST:
1004 	case VAR_DICT:
1005 	    return equal_type(type1->tt_member, type2->tt_member, flags);
1006 	case VAR_FUNC:
1007 	case VAR_PARTIAL:
1008 	    if (!equal_type(type1->tt_member, type2->tt_member, flags)
1009 		    || type1->tt_argcount != type2->tt_argcount)
1010 		return FALSE;
1011 	    if (type1->tt_argcount < 0
1012 			   || type1->tt_args == NULL || type2->tt_args == NULL)
1013 		return TRUE;
1014 	    for (i = 0; i < type1->tt_argcount; ++i)
1015 		if ((flags & ETYPE_ARG_UNKNOWN) == 0
1016 			&& !equal_type(type1->tt_args[i], type2->tt_args[i],
1017 									flags))
1018 		    return FALSE;
1019 	    return TRUE;
1020     }
1021     return TRUE;
1022 }
1023 
1024 /*
1025  * Find the common type of "type1" and "type2" and put it in "dest".
1026  * "type2" and "dest" may be the same.
1027  */
1028     void
1029 common_type(type_T *type1, type_T *type2, type_T **dest, garray_T *type_gap)
1030 {
1031     if (equal_type(type1, type2, 0))
1032     {
1033 	*dest = type1;
1034 	return;
1035     }
1036 
1037     // If either is VAR_UNKNOWN use the other type.  An empty list/dict has no
1038     // specific type.
1039     if (type1 == NULL || type1->tt_type == VAR_UNKNOWN)
1040     {
1041 	*dest = type2;
1042 	return;
1043     }
1044     if (type2 == NULL || type2->tt_type == VAR_UNKNOWN)
1045     {
1046 	*dest = type1;
1047 	return;
1048     }
1049 
1050     if (type1->tt_type == type2->tt_type)
1051     {
1052 	if (type1->tt_type == VAR_LIST || type2->tt_type == VAR_DICT)
1053 	{
1054 	    type_T *common;
1055 
1056 	    common_type(type1->tt_member, type2->tt_member, &common, type_gap);
1057 	    if (type1->tt_type == VAR_LIST)
1058 		*dest = get_list_type(common, type_gap);
1059 	    else
1060 		*dest = get_dict_type(common, type_gap);
1061 	    return;
1062 	}
1063 	if (type1->tt_type == VAR_FUNC)
1064 	{
1065 	    type_T *common;
1066 
1067 	    common_type(type1->tt_member, type2->tt_member, &common, type_gap);
1068 	    if (type1->tt_argcount == type2->tt_argcount
1069 						    && type1->tt_argcount >= 0)
1070 	    {
1071 		int argcount = type1->tt_argcount;
1072 		int i;
1073 
1074 		*dest = alloc_func_type(common, argcount, type_gap);
1075 		if (type1->tt_args != NULL && type2->tt_args != NULL)
1076 		{
1077 		    if (func_type_add_arg_types(*dest, argcount,
1078 							     type_gap) == OK)
1079 			for (i = 0; i < argcount; ++i)
1080 			    common_type(type1->tt_args[i], type2->tt_args[i],
1081 					       &(*dest)->tt_args[i], type_gap);
1082 		}
1083 	    }
1084 	    else
1085 		// Use -1 for "tt_argcount" to indicate an unknown number of
1086 		// arguments.
1087 		*dest = alloc_func_type(common, -1, type_gap);
1088 
1089 	    // Use the minimum of min_argcount.
1090 	    (*dest)->tt_min_argcount =
1091 			type1->tt_min_argcount < type2->tt_min_argcount
1092 			     ? type1->tt_min_argcount : type2->tt_min_argcount;
1093 	    return;
1094 	}
1095     }
1096 
1097     *dest = &t_any;
1098 }
1099 
1100 /*
1101  * Get the member type of a dict or list from the items on the stack.
1102  * "stack_top" points just after the last type on the type stack.
1103  * For a list "skip" is 1, for a dict "skip" is 2, keys are skipped.
1104  * Returns &t_void for an empty list or dict.
1105  * Otherwise finds the common type of all items.
1106  */
1107     type_T *
1108 get_member_type_from_stack(
1109 	type_T	    **stack_top,
1110 	int	    count,
1111 	int	    skip,
1112 	garray_T    *type_gap)
1113 {
1114     int	    i;
1115     type_T  *result;
1116     type_T  *type;
1117 
1118     // Use "any" for an empty list or dict.
1119     if (count == 0)
1120 	return &t_unknown;
1121 
1122     // Use the first value type for the list member type, then find the common
1123     // type from following items.
1124     result = *(stack_top -(count * skip) + skip - 1);
1125     for (i = 1; i < count; ++i)
1126     {
1127 	if (result == &t_any)
1128 	    break;  // won't get more common
1129 	type = *(stack_top -((count - i) * skip) + skip - 1);
1130 	common_type(type, result, &result, type_gap);
1131     }
1132 
1133     return result;
1134 }
1135 
1136     char *
1137 vartype_name(vartype_T type)
1138 {
1139     switch (type)
1140     {
1141 	case VAR_UNKNOWN: break;
1142 	case VAR_ANY: return "any";
1143 	case VAR_VOID: return "void";
1144 	case VAR_SPECIAL: return "special";
1145 	case VAR_BOOL: return "bool";
1146 	case VAR_NUMBER: return "number";
1147 	case VAR_FLOAT: return "float";
1148 	case VAR_STRING: return "string";
1149 	case VAR_BLOB: return "blob";
1150 	case VAR_JOB: return "job";
1151 	case VAR_CHANNEL: return "channel";
1152 	case VAR_LIST: return "list";
1153 	case VAR_DICT: return "dict";
1154 	case VAR_INSTR: return "instr";
1155 
1156 	case VAR_FUNC:
1157 	case VAR_PARTIAL: return "func";
1158     }
1159     return "unknown";
1160 }
1161 
1162 /*
1163  * Return the name of a type.
1164  * The result may be in allocated memory, in which case "tofree" is set.
1165  */
1166     char *
1167 type_name(type_T *type, char **tofree)
1168 {
1169     char *name;
1170 
1171     *tofree = NULL;
1172     if (type == NULL)
1173 	return "[unknown]";
1174     name = vartype_name(type->tt_type);
1175     if (type->tt_type == VAR_LIST || type->tt_type == VAR_DICT)
1176     {
1177 	char *member_free;
1178 	char *member_name = type_name(type->tt_member, &member_free);
1179 	size_t len;
1180 
1181 	len = STRLEN(name) + STRLEN(member_name) + 3;
1182 	*tofree = alloc(len);
1183 	if (*tofree != NULL)
1184 	{
1185 	    vim_snprintf(*tofree, len, "%s<%s>", name, member_name);
1186 	    vim_free(member_free);
1187 	    return *tofree;
1188 	}
1189     }
1190     if (type->tt_type == VAR_FUNC)
1191     {
1192 	garray_T    ga;
1193 	int	    i;
1194 	int	    varargs = (type->tt_flags & TTFLAG_VARARGS) ? 1 : 0;
1195 
1196 	ga_init2(&ga, 1, 100);
1197 	if (ga_grow(&ga, 20) == FAIL)
1198 	    return "[unknown]";
1199 	STRCPY(ga.ga_data, "func(");
1200 	ga.ga_len += 5;
1201 
1202 	for (i = 0; i < type->tt_argcount; ++i)
1203 	{
1204 	    char *arg_free = NULL;
1205 	    char *arg_type;
1206 	    int  len;
1207 
1208 	    if (type->tt_args == NULL)
1209 		arg_type = "[unknown]";
1210 	    else
1211 		arg_type = type_name(type->tt_args[i], &arg_free);
1212 	    if (i > 0)
1213 	    {
1214 		STRCPY((char *)ga.ga_data + ga.ga_len, ", ");
1215 		ga.ga_len += 2;
1216 	    }
1217 	    len = (int)STRLEN(arg_type);
1218 	    if (ga_grow(&ga, len + 8) == FAIL)
1219 	    {
1220 		vim_free(arg_free);
1221 		ga_clear(&ga);
1222 		return "[unknown]";
1223 	    }
1224 	    if (varargs && i == type->tt_argcount - 1)
1225 		ga_concat(&ga, (char_u *)"...");
1226 	    else if (i >= type->tt_min_argcount)
1227 		*((char *)ga.ga_data + ga.ga_len++) = '?';
1228 	    ga_concat(&ga, (char_u *)arg_type);
1229 	    vim_free(arg_free);
1230 	}
1231 	if (type->tt_argcount < 0)
1232 	    // any number of arguments
1233 	    ga_concat(&ga, (char_u *)"...");
1234 
1235 	if (type->tt_member == &t_void)
1236 	    STRCPY((char *)ga.ga_data + ga.ga_len, ")");
1237 	else
1238 	{
1239 	    char *ret_free;
1240 	    char *ret_name = type_name(type->tt_member, &ret_free);
1241 	    int  len;
1242 
1243 	    len = (int)STRLEN(ret_name) + 4;
1244 	    if (ga_grow(&ga, len) == FAIL)
1245 	    {
1246 		vim_free(ret_free);
1247 		ga_clear(&ga);
1248 		return "[unknown]";
1249 	    }
1250 	    STRCPY((char *)ga.ga_data + ga.ga_len, "): ");
1251 	    STRCPY((char *)ga.ga_data + ga.ga_len + 3, ret_name);
1252 	    vim_free(ret_free);
1253 	}
1254 	*tofree = ga.ga_data;
1255 	return ga.ga_data;
1256     }
1257 
1258     return name;
1259 }
1260 
1261 /*
1262  * "typename(expr)" function
1263  */
1264     void
1265 f_typename(typval_T *argvars, typval_T *rettv)
1266 {
1267     garray_T	type_list;
1268     type_T	*type;
1269     char	*tofree;
1270     char	*name;
1271 
1272     rettv->v_type = VAR_STRING;
1273     ga_init2(&type_list, sizeof(type_T *), 10);
1274     type = typval2type(argvars, get_copyID(), &type_list, TRUE);
1275     name = type_name(type, &tofree);
1276     if (tofree != NULL)
1277 	rettv->vval.v_string = (char_u *)tofree;
1278     else
1279     {
1280 	rettv->vval.v_string = vim_strsave((char_u *)name);
1281 	vim_free(tofree);
1282     }
1283     clear_type_list(&type_list);
1284 }
1285 
1286 #endif // FEAT_EVAL
1287