xref: /netbsd-src/external/gpl3/gdb.old/dist/gdb/unittests/array-view-selftests.c (revision ccd9df534e375a4366c5b55f23782053c7a98d82)
1 /* Self tests for array_view for GDB, the GNU debugger.
2 
3    Copyright (C) 2017-2020 Free Software Foundation, Inc.
4 
5    This file is part of GDB.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 3 of the License, or
10    (at your option) any later version.
11 
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
19 
20 #include "defs.h"
21 #include "gdbsupport/selftest.h"
22 #include "gdbsupport/array-view.h"
23 #include <array>
24 
25 namespace selftests {
26 namespace array_view_tests {
27 
28 /* Triviality checks.  */
29 #define CHECK_TRAIT(TRAIT)			\
30   static_assert (std::TRAIT<gdb::array_view<gdb_byte>>::value, "")
31 
32 #if HAVE_IS_TRIVIALLY_COPYABLE
33 
34 CHECK_TRAIT (is_trivially_copyable);
35 CHECK_TRAIT (is_trivially_move_assignable);
36 CHECK_TRAIT (is_trivially_move_constructible);
37 CHECK_TRAIT (is_trivially_destructible);
38 
39 #endif
40 
41 #undef CHECK_TRAIT
42 
43 /* Wrapper around std::is_convertible to make the code using it a bit
44    shorter.  (With C++14 we'd use a variable template instead.)  */
45 
46 template<typename From, typename To>
47 static constexpr bool
48 is_convertible ()
49 {
50   return std::is_convertible<From, To>::value;
51 }
52 
53 /* Check for implicit conversion to immutable and mutable views.  */
54 
55 static constexpr bool
56 check_convertible ()
57 {
58   using T = gdb_byte;
59   using gdb::array_view;
60 
61   return (true
62 	  /* immutable array_view */
63 	  &&  is_convertible<const T (&) [1],	array_view<const T>> ()
64 	  &&  is_convertible<T (&) [1], 	array_view<const T>> ()
65 	  &&  is_convertible<const T, 		array_view<const T>> ()
66 	  &&  is_convertible<T, 		array_view<const T>> ()
67 
68 	  /* mutable array_view */
69 	  &&  is_convertible<T (&) [1], 	array_view<T>> ()
70 	  && !is_convertible<const T (&) [1],	array_view<T>> ()
71 	  &&  is_convertible<T, 		array_view<T>> ()
72 	  && !is_convertible<const T,		array_view<T>> ()
73 
74 	  /* While float is implicitly convertible to gdb_byte, we
75 	     don't want implicit float->array_view<gdb_byte>
76 	     conversion.  */
77 	  && !is_convertible<float, 		array_view<const T>> ()
78 	  && !is_convertible<float, 		array_view<T>> ());
79 }
80 
81 static_assert (check_convertible (), "");
82 
83 namespace no_slicing
84 {
85 struct A { int i; };
86 struct B : A { int j; };
87 struct C : A { int l; };
88 
89 /* Check that there's no array->view conversion for arrays of derived
90    types or subclasses.  */
91 static constexpr bool
92 check ()
93 {
94   using gdb::array_view;
95 
96   return (true
97 
98 	  /* array->view  */
99 
100 	  &&  is_convertible <A (&)[1], array_view<A>> ()
101 	  && !is_convertible <B (&)[1], array_view<A>> ()
102 	  && !is_convertible <C (&)[1], array_view<A>> ()
103 
104 	  && !is_convertible <A (&)[1], array_view<B>> ()
105 	  &&  is_convertible <B (&)[1], array_view<B>> ()
106 	  && !is_convertible <C (&)[1], array_view<B>> ()
107 
108 	  /* elem->view  */
109 
110 	  &&  is_convertible <A, array_view<A>> ()
111 	  && !is_convertible <B, array_view<A>> ()
112 	  && !is_convertible <C, array_view<A>> ()
113 
114 	  && !is_convertible <A, array_view<B>> ()
115 	  &&  is_convertible <B, array_view<B>> ()
116 	  && !is_convertible <C, array_view<B>> ());
117 }
118 
119 } /* namespace no_slicing */
120 
121 static_assert (no_slicing::check (), "");
122 
123 /* Check that array_view implicitly converts from std::vector.  */
124 
125 static constexpr bool
126 check_convertible_from_std_vector ()
127 {
128   using gdb::array_view;
129   using T = gdb_byte;
130 
131   /* Note there's no such thing as std::vector<const T>.  */
132 
133   return (true
134 	  &&  is_convertible <std::vector<T>, array_view<T>> ()
135 	  &&  is_convertible <std::vector<T>, array_view<const T>> ());
136 }
137 
138 static_assert (check_convertible_from_std_vector (), "");
139 
140 /* Check that array_view implicitly converts from std::array.  */
141 
142 static constexpr bool
143 check_convertible_from_std_array ()
144 {
145   using gdb::array_view;
146   using T = gdb_byte;
147 
148   /* Note: a non-const T view can't refer to a const T array.  */
149 
150   return (true
151 	  &&  is_convertible <std::array<T, 1>,		array_view<T>> ()
152 	  &&  is_convertible <std::array<T, 1>,		array_view<const T>> ()
153 	  && !is_convertible <std::array<const T, 1>,	array_view<T>> ()
154 	  &&  is_convertible <std::array<const T, 1>,	array_view<const T>> ());
155 }
156 
157 static_assert (check_convertible_from_std_array (), "");
158 
159 /* Check that VIEW views C (a container like std::vector/std::array)
160    correctly.  */
161 
162 template<typename View, typename Container>
163 static bool
164 check_container_view (const View &view, const Container &c)
165 {
166   if (view.empty ())
167     return false;
168   if (view.size () != c.size ())
169     return false;
170   if (view.data () != c.data ())
171     return false;
172   for (size_t i = 0; i < c.size (); i++)
173     {
174       if (&view[i] != &c[i])
175 	return false;
176       if (view[i] != c[i])
177 	return false;
178     }
179   return true;
180 }
181 
182 /* Check that VIEW views E (an object of the type of a view element)
183    correctly.  */
184 
185 template<typename View, typename Elem>
186 static bool
187 check_elem_view (const View &view, const Elem &e)
188 {
189   if (view.empty ())
190     return false;
191   if (view.size () != 1)
192     return false;
193   if (view.data () != &e)
194     return false;
195   if (&view[0] != &e)
196     return false;
197   if (view[0] != e)
198     return false;
199   return true;
200 }
201 
202 /* Check for operator[].  The first overload is taken iff
203    'view<T>()[0] = T()' is a valid expression.  */
204 
205 template<typename View,
206 	 typename = decltype (std::declval<View> ()[0]
207 			      = std::declval<typename View::value_type> ())>
208 static bool
209 check_op_subscript (const View &view)
210 {
211   return true;
212 }
213 
214 /* This overload is taken iff 'view<T>()[0] = T()' is not a valid
215    expression.  */
216 
217 static bool
218 check_op_subscript (...)
219 {
220   return false;
221 }
222 
223 /* Check construction with pointer + size.  This is a template in
224    order to test both gdb_byte and const gdb_byte.  */
225 
226 template<typename T>
227 static void
228 check_ptr_size_ctor ()
229 {
230   T data[] = {0x11, 0x22, 0x33, 0x44};
231 
232   gdb::array_view<T> view (data + 1, 2);
233 
234   SELF_CHECK (!view.empty ());
235   SELF_CHECK (view.size () == 2);
236   SELF_CHECK (view.data () == &data[1]);
237   SELF_CHECK (view[0] == data[1]);
238   SELF_CHECK (view[1] == data[2]);
239 
240   gdb::array_view<const T> cview (data + 1, 2);
241   SELF_CHECK (!cview.empty ());
242   SELF_CHECK (cview.size () == 2);
243   SELF_CHECK (cview.data () == &data[1]);
244   SELF_CHECK (cview[0] == data[1]);
245   SELF_CHECK (cview[1] == data[2]);
246 }
247 
248 /* Asserts std::is_constructible.  */
249 
250 template<typename T, typename... Args>
251 static constexpr bool
252 require_not_constructible ()
253 {
254   static_assert (!std::is_constructible<T, Args...>::value, "");
255 
256   /* constexpr functions can't return void in C++11 (N3444).  */
257   return true;
258 };
259 
260 /* Check the array_view<T>(PTR, SIZE) ctor, when T is a pointer.  */
261 
262 static void
263 check_ptr_size_ctor2 ()
264 {
265   struct A {};
266   A an_a;
267 
268   A *array[] = { &an_a };
269   const A * const carray[] = { &an_a };
270 
271   gdb::array_view<A *> v1 = {array, ARRAY_SIZE (array)};
272   gdb::array_view<A *> v2 = {array, (char) ARRAY_SIZE (array)};
273   gdb::array_view<A * const> v3 = {array, ARRAY_SIZE (array)};
274   gdb::array_view<const A * const> cv1 = {carray, ARRAY_SIZE (carray)};
275 
276   require_not_constructible<gdb::array_view<A *>, decltype (carray), size_t> ();
277 
278   SELF_CHECK (v1[0] == array[0]);
279   SELF_CHECK (v2[0] == array[0]);
280   SELF_CHECK (v3[0] == array[0]);
281 
282   SELF_CHECK (!v1.empty ());
283   SELF_CHECK (v1.size () == 1);
284   SELF_CHECK (v1.data () == &array[0]);
285 
286   SELF_CHECK (cv1[0] == carray[0]);
287 
288   SELF_CHECK (!cv1.empty ());
289   SELF_CHECK (cv1.size () == 1);
290   SELF_CHECK (cv1.data () == &carray[0]);
291 }
292 
293 /* Check construction with a pair of pointers.  This is a template in
294    order to test both gdb_byte and const gdb_byte.  */
295 
296 template<typename T>
297 static void
298 check_ptr_ptr_ctor ()
299 {
300   T data[] = {0x11, 0x22, 0x33, 0x44};
301 
302   gdb::array_view<T> view (data + 1, data + 3);
303 
304   SELF_CHECK (!view.empty ());
305   SELF_CHECK (view.size () == 2);
306   SELF_CHECK (view.data () == &data[1]);
307   SELF_CHECK (view[0] == data[1]);
308   SELF_CHECK (view[1] == data[2]);
309 
310   gdb_byte array[] = {0x11, 0x22, 0x33, 0x44};
311   const gdb_byte *p1 = array;
312   gdb_byte *p2 = array + ARRAY_SIZE (array);
313   gdb::array_view<const gdb_byte> view2 (p1, p2);
314 }
315 
316 /* Check construction with a pair of pointers of mixed constness.  */
317 
318 static void
319 check_ptr_ptr_mixed_cv ()
320 {
321   gdb_byte array[] = {0x11, 0x22, 0x33, 0x44};
322   const gdb_byte *cp = array;
323   gdb_byte *p = array;
324   gdb::array_view<const gdb_byte> view1 (cp, p);
325   gdb::array_view<const gdb_byte> view2 (p, cp);
326   SELF_CHECK (view1.empty ());
327   SELF_CHECK (view2.empty ());
328 }
329 
330 /* Check range-for support (i.e., begin()/end()).  This is a template
331    in order to test both gdb_byte and const gdb_byte.  */
332 
333 template<typename T>
334 static void
335 check_range_for ()
336 {
337   T data[] = {1, 2, 3, 4};
338   gdb::array_view<T> view (data);
339 
340   typename std::decay<T>::type sum = 0;
341   for (auto &elem : view)
342     sum += elem;
343   SELF_CHECK (sum == 1 + 2 + 3 + 4);
344 }
345 
346 /* Entry point.  */
347 
348 static void
349 run_tests ()
350 {
351   /* Empty views.  */
352   {
353     constexpr gdb::array_view<gdb_byte> view1;
354     constexpr gdb::array_view<const gdb_byte> view2;
355 
356     static_assert (view1.empty (), "");
357     static_assert (view1.data () == nullptr, "");
358     static_assert (view1.size () == 0, "");
359     static_assert (view2.empty (), "");
360     static_assert (view2.size () == 0, "");
361     static_assert (view2.data () == nullptr, "");
362   }
363 
364   std::vector<gdb_byte> vec = {0x11, 0x22, 0x33, 0x44 };
365   std::array<gdb_byte, 4> array = {{0x11, 0x22, 0x33, 0x44}};
366 
367   /* Various tests of views over std::vector.  */
368   {
369     gdb::array_view<gdb_byte> view = vec;
370     SELF_CHECK (check_container_view (view, vec));
371     gdb::array_view<const gdb_byte> cview = vec;
372     SELF_CHECK (check_container_view (cview, vec));
373   }
374 
375   /* Likewise, over std::array.  */
376   {
377     gdb::array_view<gdb_byte> view = array;
378     SELF_CHECK (check_container_view (view, array));
379     gdb::array_view<gdb_byte> cview = array;
380     SELF_CHECK (check_container_view (cview, array));
381   }
382 
383   /* op=(std::vector/std::array/elem) */
384   {
385     gdb::array_view<gdb_byte> view;
386 
387     view = vec;
388     SELF_CHECK (check_container_view (view, vec));
389     view = std::move (vec);
390     SELF_CHECK (check_container_view (view, vec));
391 
392     view = array;
393     SELF_CHECK (check_container_view (view, array));
394     view = std::move (array);
395     SELF_CHECK (check_container_view (view, array));
396 
397     gdb_byte elem = 0;
398     view = elem;
399     SELF_CHECK (check_elem_view (view, elem));
400     view = std::move (elem);
401     SELF_CHECK (check_elem_view (view, elem));
402   }
403 
404   /* Test copy/move ctor and mutable->immutable conversion.  */
405   {
406     gdb_byte data[] = {0x11, 0x22, 0x33, 0x44};
407     gdb::array_view<gdb_byte> view1 = data;
408     gdb::array_view<gdb_byte> view2 = view1;
409     gdb::array_view<gdb_byte> view3 = std::move (view1);
410     gdb::array_view<const gdb_byte> cview1 = data;
411     gdb::array_view<const gdb_byte> cview2 = cview1;
412     gdb::array_view<const gdb_byte> cview3 = std::move (cview1);
413     SELF_CHECK (view1[0] == data[0]);
414     SELF_CHECK (view2[0] == data[0]);
415     SELF_CHECK (view3[0] == data[0]);
416     SELF_CHECK (cview1[0] == data[0]);
417     SELF_CHECK (cview2[0] == data[0]);
418     SELF_CHECK (cview3[0] == data[0]);
419   }
420 
421   /* Same, but op=(view).  */
422   {
423     gdb_byte data[] = {0x55, 0x66, 0x77, 0x88};
424     gdb::array_view<gdb_byte> view1;
425     gdb::array_view<gdb_byte> view2;
426     gdb::array_view<gdb_byte> view3;
427     gdb::array_view<const gdb_byte> cview1;
428     gdb::array_view<const gdb_byte> cview2;
429     gdb::array_view<const gdb_byte> cview3;
430 
431     view1 = data;
432     view2 = view1;
433     view3 = std::move (view1);
434     cview1 = data;
435     cview2 = cview1;
436     cview3 = std::move (cview1);
437     SELF_CHECK (view1[0] == data[0]);
438     SELF_CHECK (view2[0] == data[0]);
439     SELF_CHECK (view3[0] == data[0]);
440     SELF_CHECK (cview1[0] == data[0]);
441     SELF_CHECK (cview2[0] == data[0]);
442     SELF_CHECK (cview3[0] == data[0]);
443   }
444 
445   /* op[] */
446   {
447     std::vector<gdb_byte> vec2 = {0x11, 0x22};
448     gdb::array_view<gdb_byte> view = vec2;
449     gdb::array_view<const gdb_byte> cview = vec2;
450 
451     /* Check that op[] on a non-const view of non-const T returns a
452        mutable reference.  */
453     view[0] = 0x33;
454     SELF_CHECK (vec2[0] == 0x33);
455 
456     /* OTOH, check that assigning through op[] on a view of const T
457        wouldn't compile.  */
458     SELF_CHECK (!check_op_subscript (cview));
459     /* For completeness.  */
460     SELF_CHECK (check_op_subscript (view));
461   }
462 
463   check_ptr_size_ctor<const gdb_byte> ();
464   check_ptr_size_ctor<gdb_byte> ();
465   check_ptr_size_ctor2 ();
466   check_ptr_ptr_ctor<const gdb_byte> ();
467   check_ptr_ptr_ctor<gdb_byte> ();
468   check_ptr_ptr_mixed_cv ();
469 
470   check_range_for<gdb_byte> ();
471   check_range_for<const gdb_byte> ();
472 
473   /* Check that the right ctor overloads are taken when the element is
474      a container.  */
475   {
476     using Vec = std::vector<gdb_byte>;
477     Vec vecs[3];
478 
479     gdb::array_view<Vec> view_array = vecs;
480     SELF_CHECK (view_array.size () == 3);
481 
482     Vec elem;
483     gdb::array_view<Vec> view_elem = elem;
484     SELF_CHECK (view_elem.size () == 1);
485   }
486 
487   /* gdb::make_array_view, int length.  */
488   {
489     gdb_byte data[] = {0x55, 0x66, 0x77, 0x88};
490     int len = sizeof (data) / sizeof (data[0]);
491     auto view = gdb::make_array_view (data, len);
492 
493     SELF_CHECK (view.data () == data);
494     SELF_CHECK (view.size () == len);
495 
496     for (size_t i = 0; i < len; i++)
497       SELF_CHECK (view[i] == data[i]);
498   }
499 
500   /* Test slicing.  */
501   {
502     gdb_byte data[] = {0x55, 0x66, 0x77, 0x88, 0x99};
503     gdb::array_view<gdb_byte> view = data;
504 
505     {
506       auto slc = view.slice (1, 3);
507       SELF_CHECK (slc.data () == data + 1);
508       SELF_CHECK (slc.size () == 3);
509       SELF_CHECK (slc[0] == data[1]);
510       SELF_CHECK (slc[0] == view[1]);
511     }
512 
513     {
514       auto slc = view.slice (2);
515       SELF_CHECK (slc.data () == data + 2);
516       SELF_CHECK (slc.size () == 3);
517       SELF_CHECK (slc[0] == view[2]);
518       SELF_CHECK (slc[0] == data[2]);
519     }
520   }
521 }
522 
523 } /* namespace array_view_tests */
524 } /* namespace selftests */
525 
526 void _initialize_array_view_selftests ();
527 void
528 _initialize_array_view_selftests ()
529 {
530   selftests::register_test ("array_view",
531 			    selftests::array_view_tests::run_tests);
532 }
533