Branch data Line data Source code
1 : : /* Find near-matches for strings.
2 : : Copyright (C) 2015-2025 Free Software Foundation, Inc.
3 : :
4 : : This file is part of GCC.
5 : :
6 : : GCC is free software; you can redistribute it and/or modify it under
7 : : the terms of the GNU General Public License as published by the Free
8 : : Software Foundation; either version 3, or (at your option) any later
9 : : version.
10 : :
11 : : GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 : : WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 : : FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 : : for more details.
15 : :
16 : : You should have received a copy of the GNU General Public License
17 : : along with GCC; see the file COPYING3. If not see
18 : : <http://www.gnu.org/licenses/>. */
19 : :
20 : : #include "config.h"
21 : : #include "system.h"
22 : : #include "coretypes.h"
23 : : #include "tm.h"
24 : : #include "tree.h"
25 : : #include "spellcheck.h"
26 : : #include "selftest.h"
27 : :
28 : : /* Cost of a case transformation. */
29 : : #define CASE_COST 1
30 : :
31 : : /* Cost of another kind of edit. */
32 : : #define BASE_COST 2
33 : :
34 : : /* Get the edit distance between the two strings: the minimal
35 : : number of edits that are needed to change one string into another,
36 : : where edits can be one-character insertions, removals, or substitutions,
37 : : or transpositions of two adjacent characters (counting as one "edit").
38 : :
39 : : This implementation uses a modified variant of the Wagner-Fischer
40 : : algorithm for the Damerau-Levenshtein distance; specifically, the
41 : : "optimal string alignment distance" or "restricted edit distance"
42 : : variant. This implementation has been further modified to take
43 : : case into account. */
44 : :
45 : : edit_distance_t
46 : 5128282 : get_edit_distance (const char *s, int len_s,
47 : : const char *t, int len_t)
48 : : {
49 : 5128282 : const bool debug = false;
50 : :
51 : 5128282 : if (debug)
52 : : {
53 : : printf ("s: \"%s\" (len_s=%i)\n", s, len_s);
54 : : printf ("t: \"%s\" (len_t=%i)\n", t, len_t);
55 : : }
56 : :
57 : 5128282 : if (len_s == 0)
58 : 68 : return BASE_COST * len_t;
59 : 5128214 : if (len_t == 0)
60 : 60 : return BASE_COST * len_s;
61 : :
62 : : /* We effectively build a matrix where each (i, j) contains the
63 : : distance between the prefix strings s[0:j] and t[0:i].
64 : : Rather than actually build an (len_t + 1) * (len_s + 1) matrix,
65 : : we simply keep track of the last two rows, v_one_ago and v_two_ago,
66 : : and a new row, v_next, which avoids an (len_t + 1) * (len_s + 1)
67 : : allocation and memory accesses in favor of three (len_s + 1)
68 : : allocations. These could potentially be
69 : : statically-allocated if we impose a maximum length on the
70 : : strings of interest. */
71 : 5128154 : edit_distance_t *v_two_ago = new edit_distance_t[len_s + 1];
72 : 5128154 : edit_distance_t *v_one_ago = new edit_distance_t[len_s + 1];
73 : 5128154 : edit_distance_t *v_next = new edit_distance_t[len_s + 1];
74 : :
75 : : /* The first row is for the case of an empty target string, which
76 : : we can reach by deleting every character in the source string. */
77 : 92564230 : for (int i = 0; i < len_s + 1; i++)
78 : 87436076 : v_one_ago[i] = i * BASE_COST;
79 : :
80 : : /* Build successive rows. */
81 : 90349465 : for (int i = 0; i < len_t; i++)
82 : : {
83 : 85221311 : if (debug)
84 : : {
85 : : printf ("i:%i v_one_ago = ", i);
86 : : for (int j = 0; j < len_s + 1; j++)
87 : : printf ("%i ", v_one_ago[j]);
88 : : printf ("\n");
89 : : }
90 : :
91 : : /* The initial column is for the case of an empty source string; we
92 : : can reach prefixes of the target string of length i
93 : : by inserting i characters. */
94 : 85221311 : v_next[0] = (i + 1) * BASE_COST;
95 : :
96 : : /* Build the rest of the row by considering neighbors to
97 : : the north, west and northwest. */
98 : 1502603867 : for (int j = 0; j < len_s; j++)
99 : : {
100 : 1417382556 : edit_distance_t cost;
101 : :
102 : 1417382556 : if (s[j] == t[i])
103 : : cost = 0;
104 : 1326287580 : else if (TOLOWER (s[j]) == TOLOWER (t[i]))
105 : : cost = CASE_COST;
106 : : else
107 : 1322160284 : cost = BASE_COST;
108 : 1417382556 : edit_distance_t deletion = v_next[j] + BASE_COST;
109 : 1417382556 : edit_distance_t insertion = v_one_ago[j + 1] + BASE_COST;
110 : 1417382556 : edit_distance_t substitution = v_one_ago[j] + cost;
111 : 1417382556 : edit_distance_t cheapest = MIN (deletion, insertion);
112 : 1417382556 : cheapest = MIN (cheapest, substitution);
113 : 1417382556 : if (i > 0 && j > 0 && s[j] == t[i - 1] && s[j - 1] == t[i])
114 : : {
115 : 6341450 : edit_distance_t transposition = v_two_ago[j - 1] + BASE_COST;
116 : 6341450 : cheapest = MIN (cheapest, transposition);
117 : : }
118 : 1417382556 : v_next[j + 1] = cheapest;
119 : : }
120 : :
121 : : /* Prepare to move on to next row. */
122 : 1587825178 : for (int j = 0; j < len_s + 1; j++)
123 : : {
124 : 1502603867 : v_two_ago[j] = v_one_ago[j];
125 : 1502603867 : v_one_ago[j] = v_next[j];
126 : : }
127 : : }
128 : :
129 : 5128154 : if (debug)
130 : : {
131 : : printf ("final v_next = ");
132 : : for (int j = 0; j < len_s + 1; j++)
133 : : printf ("%i ", v_next[j]);
134 : : printf ("\n");
135 : : }
136 : :
137 : 5128154 : edit_distance_t result = v_next[len_s];
138 : 5128154 : delete[] v_two_ago;
139 : 5128154 : delete[] v_one_ago;
140 : 5128154 : delete[] v_next;
141 : 5128154 : return result;
142 : : }
143 : :
144 : : /* Get the edit distance between two nil-terminated strings. */
145 : :
146 : : edit_distance_t
147 : 752 : get_edit_distance (const char *s, const char *t)
148 : : {
149 : 752 : return get_edit_distance (s, strlen (s), t, strlen (t));
150 : : }
151 : :
152 : : /* Given TARGET, a non-NULL string, and CANDIDATES, a non-NULL ptr to
153 : : an autovec of non-NULL strings, determine which element within
154 : : CANDIDATES has the lowest edit distance to TARGET. If there are
155 : : multiple elements with the same minimal distance, the first in the
156 : : vector wins.
157 : :
158 : : If more than half of the letters were misspelled, the suggestion is
159 : : likely to be meaningless, so return NULL for this case. */
160 : :
161 : : const char *
162 : 859 : find_closest_string (const char *target,
163 : : const auto_vec<const char *> *candidates)
164 : : {
165 : 859 : gcc_assert (target);
166 : 859 : gcc_assert (candidates);
167 : :
168 : 859 : int i;
169 : 859 : const char *candidate;
170 : 859 : best_match<const char *, const char *> bm (target);
171 : 5365040 : FOR_EACH_VEC_ELT (*candidates, i, candidate)
172 : : {
173 : 5363322 : gcc_assert (candidate);
174 : 5363322 : bm.consider (candidate);
175 : : }
176 : :
177 : 859 : return bm.get_best_meaningful_candidate ();
178 : : }
179 : :
180 : : /* Generate the maximum edit distance for which we consider a suggestion
181 : : to be meaningful, given a goal of length GOAL_LEN and a candidate of
182 : : length CANDIDATE_LEN.
183 : :
184 : : This is a third of the length of the candidate or of the goal,
185 : : whichever is bigger. */
186 : :
187 : : edit_distance_t
188 : 5239547 : get_edit_distance_cutoff (size_t goal_len, size_t candidate_len)
189 : : {
190 : 5239547 : size_t max_length = MAX (goal_len, candidate_len);
191 : 5239547 : size_t min_length = MIN (goal_len, candidate_len);
192 : :
193 : 5239547 : gcc_assert (max_length >= min_length);
194 : :
195 : : /* Special case: don't offer suggestions for a pair of
196 : : length == 1 strings (or empty strings). */
197 : 5239547 : if (max_length <= 1)
198 : : return 0;
199 : :
200 : : /* If the lengths are close, then round down. */
201 : 5231157 : if (max_length - min_length <= 1)
202 : : /* ...but allow an edit distance of at least 1. */
203 : 792189 : return BASE_COST * MAX (max_length / 3, 1);
204 : :
205 : : /* Otherwise, round up (thus giving a little extra leeway to some cases
206 : : involving insertions/deletions). */
207 : 4438968 : return BASE_COST * (max_length + 2) / 3;
208 : : }
209 : :
210 : : #if CHECKING_P
211 : :
212 : : namespace selftest {
213 : :
214 : : /* Selftests. */
215 : :
216 : : /* Verify that get_edit_distance (A, B) equals the expected value. */
217 : :
218 : : static void
219 : 240 : test_get_edit_distance_one_way (const char *a, const char *b,
220 : : edit_distance_t expected)
221 : : {
222 : 240 : edit_distance_t actual = get_edit_distance (a, b);
223 : 240 : ASSERT_EQ (actual, expected);
224 : 240 : }
225 : :
226 : : /* Verify that both
227 : : get_edit_distance (A, B)
228 : : and
229 : : get_edit_distance (B, A)
230 : : equal the expected value, to ensure that the function is symmetric. */
231 : :
232 : : static void
233 : 120 : test_get_edit_distance_both_ways (const char *a, const char *b,
234 : : edit_distance_t expected)
235 : : {
236 : 120 : test_get_edit_distance_one_way (a, b, expected);
237 : 120 : test_get_edit_distance_one_way (b, a, expected);
238 : 120 : }
239 : :
240 : : /* Verify get_edit_distance for a variety of pairs of pre-canned
241 : : inputs, comparing against known-good values. */
242 : :
243 : : static void
244 : 4 : test_edit_distances ()
245 : : {
246 : 4 : test_get_edit_distance_both_ways ("", "nonempty",
247 : : BASE_COST * strlen ("nonempty"));
248 : 4 : test_get_edit_distance_both_ways ("saturday", "sunday",
249 : : BASE_COST * 3);
250 : 4 : test_get_edit_distance_both_ways ("foo", "m_foo", BASE_COST * 2);
251 : 4 : test_get_edit_distance_both_ways ("hello_world", "HelloWorld", 4);
252 : 4 : test_get_edit_distance_both_ways
253 : 4 : ("the quick brown fox jumps over the lazy dog", "dog", BASE_COST * 40);
254 : 4 : test_get_edit_distance_both_ways
255 : 4 : ("the quick brown fox jumps over the lazy dog",
256 : : "the quick brown dog jumps over the lazy fox",
257 : : BASE_COST * 4);
258 : 4 : test_get_edit_distance_both_ways
259 : 4 : ("Lorem ipsum dolor sit amet, consectetur adipiscing elit,",
260 : : "All your base are belong to us",
261 : : BASE_COST * 44);
262 : 4 : test_get_edit_distance_both_ways ("foo", "FOO", 3);
263 : 4 : test_get_edit_distance_both_ways ("fee", "deed", BASE_COST * 2);
264 : 4 : test_get_edit_distance_both_ways ("coorzd1", "coordx1", BASE_COST * 2);
265 : 4 : test_get_edit_distance_both_ways ("assert", "sqrt", BASE_COST * 3);
266 : 4 : test_get_edit_distance_both_ways ("PATH_MAX", "INT8_MAX", BASE_COST * 3);
267 : 4 : test_get_edit_distance_both_ways ("time", "nice", BASE_COST * 2);
268 : 4 : test_get_edit_distance_both_ways ("bar", "carg", BASE_COST * 2);
269 : 4 : test_get_edit_distance_both_ways ("gtk_widget_show_all",
270 : : "GtkWidgetShowAll", 10);
271 : 4 : test_get_edit_distance_both_ways ("m_bar", "bar", BASE_COST * 2);
272 : 4 : test_get_edit_distance_both_ways ("MACRO", "MACRAME", BASE_COST * 3);
273 : 4 : test_get_edit_distance_both_ways ("ab", "ac", BASE_COST * 1);
274 : 4 : test_get_edit_distance_both_ways ("ab", "a", BASE_COST * 1);
275 : 4 : test_get_edit_distance_both_ways ("a", "b", BASE_COST * 1);
276 : 4 : test_get_edit_distance_both_ways ("nanl", "name", BASE_COST * 2);
277 : 4 : test_get_edit_distance_both_ways ("char", "bar", BASE_COST * 2);
278 : 4 : test_get_edit_distance_both_ways ("-optimize", "fsanitize", BASE_COST * 5);
279 : 4 : test_get_edit_distance_both_ways ("__DATE__", "__i386__", BASE_COST * 4);
280 : :
281 : : /* Examples where transposition helps. */
282 : 4 : test_get_edit_distance_both_ways ("ab", "ba", BASE_COST * 1);
283 : 4 : test_get_edit_distance_both_ways ("ba", "abc", BASE_COST * 2);
284 : 4 : test_get_edit_distance_both_ways ("coorzd1", "coordz1", BASE_COST * 1);
285 : 4 : test_get_edit_distance_both_ways ("abcdefghijklmnopqrstuvwxyz",
286 : : "bacdefghijklmnopqrstuvwxzy",
287 : : BASE_COST * 2);
288 : 4 : test_get_edit_distance_both_ways ("saturday", "sundya", BASE_COST * 4);
289 : 4 : test_get_edit_distance_both_ways ("signed", "singed", BASE_COST * 1);
290 : 4 : }
291 : :
292 : : /* Subroutine of test_get_edit_distance_cutoff, for emulating the
293 : : spellchecking cutoff in up to GCC 8. */
294 : :
295 : : static edit_distance_t
296 : 3600 : get_old_cutoff (size_t goal_len, size_t candidate_len)
297 : : {
298 : 3600 : return BASE_COST * MAX (goal_len, candidate_len) / 2;
299 : : }
300 : :
301 : : /* Verify that the cutoff for "meaningfulness" of suggestions is at least as
302 : : conservative as in older GCC releases.
303 : :
304 : : This should ensure that we don't offer additional meaningless
305 : : suggestions (apart from those for which transposition has helped). */
306 : :
307 : : static void
308 : 4 : test_get_edit_distance_cutoff ()
309 : : {
310 : 124 : for (size_t goal_len = 0; goal_len < 30; goal_len++)
311 : 3720 : for (size_t candidate_len = 0; candidate_len < 30; candidate_len++)
312 : 3600 : ASSERT_TRUE (get_edit_distance_cutoff (goal_len, candidate_len)
313 : : <= get_old_cutoff (goal_len, candidate_len));
314 : 4 : }
315 : :
316 : : /* Assert that CANDIDATE is offered as a suggestion for TARGET. */
317 : :
318 : : static void
319 : 20 : assert_suggested_for (const location &loc, const char *candidate,
320 : : const char *target)
321 : : {
322 : 20 : auto_vec<const char *> candidates;
323 : 20 : candidates.safe_push (candidate);
324 : 20 : ASSERT_EQ_AT (loc, candidate, find_closest_string (target, &candidates));
325 : 20 : }
326 : :
327 : : /* Assert that CANDIDATE is offered as a suggestion for TARGET. */
328 : :
329 : : #define ASSERT_SUGGESTED_FOR(CANDIDATE, TARGET) \
330 : : SELFTEST_BEGIN_STMT \
331 : : assert_suggested_for (SELFTEST_LOCATION, CANDIDATE, TARGET); \
332 : : SELFTEST_END_STMT
333 : :
334 : : /* Assert that CANDIDATE is not offered as a suggestion for TARGET. */
335 : :
336 : : static void
337 : 40 : assert_not_suggested_for (const location &loc, const char *candidate,
338 : : const char *target)
339 : : {
340 : 40 : auto_vec<const char *> candidates;
341 : 40 : candidates.safe_push (candidate);
342 : 40 : ASSERT_EQ_AT (loc, NULL, find_closest_string (target, &candidates));
343 : 40 : }
344 : :
345 : : /* Assert that CANDIDATE is not offered as a suggestion for TARGET. */
346 : :
347 : : #define ASSERT_NOT_SUGGESTED_FOR(CANDIDATE, TARGET) \
348 : : SELFTEST_BEGIN_STMT \
349 : : assert_not_suggested_for (SELFTEST_LOCATION, CANDIDATE, TARGET); \
350 : : SELFTEST_END_STMT
351 : :
352 : : /* Verify that we offer varous suggestions that are meaningful,
353 : : and that we don't offer various other ones that aren't (PR c/82967). */
354 : :
355 : : static void
356 : 4 : test_suggestions ()
357 : : {
358 : : /* Good suggestions. */
359 : :
360 : 4 : ASSERT_SUGGESTED_FOR ("m_bar", "bar");
361 : : // dist == 2, max_length == 5, min_length == 3
362 : :
363 : 4 : ASSERT_SUGGESTED_FOR ("MACRO", "MACRAME");
364 : : // dist == 3, max_length == 7, min_length == 5
365 : :
366 : 4 : ASSERT_SUGGESTED_FOR ("gtk_widget_show_all", "GtkWidgetShowAll");
367 : : // dist == 7, max_length == 16, min_length = 19
368 : :
369 : 4 : ASSERT_SUGGESTED_FOR ("ab", "ac");
370 : : // dist == 1, max_length == min_length = 2
371 : :
372 : 4 : ASSERT_SUGGESTED_FOR ("ab", "a");
373 : : // dist == 1, max_length == 2, min_length = 1
374 : :
375 : : /* Bad suggestions. */
376 : :
377 : 4 : ASSERT_NOT_SUGGESTED_FOR ("a", "b");
378 : : // dist == 1, max_length == min_length = 1
379 : :
380 : 4 : ASSERT_NOT_SUGGESTED_FOR ("sqrt", "assert");
381 : : // dist == 3, max_length 6, min_length == 4
382 : :
383 : 4 : ASSERT_NOT_SUGGESTED_FOR ("INT8_MAX", "PATH_MAX");
384 : : // dist == 3, max_length == min_length == 8
385 : :
386 : 4 : ASSERT_NOT_SUGGESTED_FOR ("nice", "time");
387 : 4 : ASSERT_NOT_SUGGESTED_FOR ("nanl", "name");
388 : : // dist == 2, max_length == min_length == 4
389 : :
390 : 4 : ASSERT_NOT_SUGGESTED_FOR ("carg", "bar");
391 : 4 : ASSERT_NOT_SUGGESTED_FOR ("char", "bar");
392 : : // dist == 2, max_length == 4, min_length == 3
393 : :
394 : 4 : ASSERT_NOT_SUGGESTED_FOR ("-optimize", "fsanitize");
395 : : // dist == 5, max_length == min_length == 9
396 : :
397 : 4 : ASSERT_NOT_SUGGESTED_FOR ("__DATE__", "__i386__");
398 : : // dist == 4, max_length == min_length == 8
399 : :
400 : 4 : ASSERT_NOT_SUGGESTED_FOR ("start_input_device", "InputDevice");
401 : : // dist == 9, max_length == 18, min_length == 11
402 : 4 : }
403 : :
404 : : /* Verify that find_closest_string is sane. */
405 : :
406 : : static void
407 : 4 : test_find_closest_string ()
408 : : {
409 : 4 : auto_vec<const char *> candidates;
410 : :
411 : : /* Verify that it can handle an empty vec. */
412 : 4 : ASSERT_EQ (NULL, find_closest_string ("", &candidates));
413 : :
414 : : /* Verify that it works sanely for non-empty vecs. */
415 : 4 : candidates.safe_push ("apple");
416 : 4 : candidates.safe_push ("banana");
417 : 4 : candidates.safe_push ("cherry");
418 : :
419 : 4 : ASSERT_STREQ ("apple", find_closest_string ("app", &candidates));
420 : 4 : ASSERT_STREQ ("banana", find_closest_string ("banyan", &candidates));
421 : 4 : ASSERT_STREQ ("cherry", find_closest_string ("berry", &candidates));
422 : 4 : ASSERT_EQ (NULL, find_closest_string ("not like the others", &candidates));
423 : :
424 : : /* The order of the vec can matter, but it should not matter for these
425 : : inputs. */
426 : 4 : candidates.truncate (0);
427 : 4 : candidates.safe_push ("cherry");
428 : 4 : candidates.safe_push ("banana");
429 : 4 : candidates.safe_push ("apple");
430 : 4 : ASSERT_STREQ ("apple", find_closest_string ("app", &candidates));
431 : 4 : ASSERT_STREQ ("banana", find_closest_string ("banyan", &candidates));
432 : 4 : ASSERT_STREQ ("cherry", find_closest_string ("berry", &candidates));
433 : 4 : ASSERT_EQ (NULL, find_closest_string ("not like the others", &candidates));
434 : :
435 : : /* If the goal string somehow makes it into the candidate list, offering
436 : : it as a suggestion will be nonsensical. Verify that we don't offer such
437 : : suggestions. */
438 : 4 : ASSERT_EQ (NULL, find_closest_string ("banana", &candidates));
439 : :
440 : : /* Example from PR 69968 where transposition helps. */
441 : 4 : candidates.truncate (0);
442 : 4 : candidates.safe_push("coordx");
443 : 4 : candidates.safe_push("coordy");
444 : 4 : candidates.safe_push("coordz");
445 : 4 : candidates.safe_push("coordx1");
446 : 4 : candidates.safe_push("coordy1");
447 : 4 : candidates.safe_push("coordz1");
448 : 4 : ASSERT_STREQ ("coordz1", find_closest_string ("coorzd1", &candidates));
449 : :
450 : 4 : candidates.truncate (0);
451 : 4 : candidates.safe_push ("DWARF_GNAT_ENCODINGS_GDB");
452 : 4 : candidates.safe_push ("DWARF_GNAT_ENCODINGS_ALL");
453 : 4 : candidates.safe_push ("DWARF_GNAT_ENCODINGS_MINIMAL");
454 : 4 : ASSERT_STREQ ("DWARF_GNAT_ENCODINGS_ALL",
455 : : find_closest_string ("DWARF_GNAT_ENCODINGS_all",
456 : : &candidates));
457 : :
458 : : /* The same as the previous test, but with a different order of
459 : : candidates. */
460 : 4 : candidates.truncate (0);
461 : 4 : candidates.safe_push ("DWARF_GNAT_ENCODINGS_ALL");
462 : 4 : candidates.safe_push ("DWARF_GNAT_ENCODINGS_GDB");
463 : 4 : candidates.safe_push ("DWARF_GNAT_ENCODINGS_MINIMAL");
464 : 4 : ASSERT_STREQ ("DWARF_GNAT_ENCODINGS_ALL",
465 : : find_closest_string ("DWARF_GNAT_ENCODINGS_all",
466 : : &candidates));
467 : :
468 : : /* Example from PR 105564 where option name with missing equal
469 : : sign should win. */
470 : 4 : candidates.truncate (0);
471 : 4 : candidates.safe_push ("-Wtrivial-auto-var-init");
472 : 4 : candidates.safe_push ("-ftrivial-auto-var-init=");
473 : 4 : ASSERT_STREQ ("-ftrivial-auto-var-init=",
474 : : find_closest_string ("-ftrivial-auto-var-init",
475 : : &candidates));
476 : 4 : }
477 : :
478 : : /* Test data for test_metric_conditions. */
479 : :
480 : : static const char * const test_data[] = {
481 : : "",
482 : : "foo",
483 : : "food",
484 : : "boo",
485 : : "1234567890123456789012345678901234567890123456789012345678901234567890",
486 : : "abc",
487 : : "ac",
488 : : "ca",
489 : : };
490 : :
491 : : /* Verify that get_edit_distance appears to be a sane distance function,
492 : : even though it doesn't satisfy the conditions for being a metric. (This
493 : : is because the triangle inequality fails to hold: the distance between
494 : : "ca" and "ac" is 1, and so is the distance between "abc" and "ac", but
495 : : the distance between "abc" and "ca" is 3. Algorithms that calculate the
496 : : true Levenshtein-Damerau metric are much more expensive.) */
497 : :
498 : : static void
499 : 4 : test_metric_conditions ()
500 : : {
501 : 4 : const int num_test_cases = ARRAY_SIZE (test_data);
502 : :
503 : 36 : for (int i = 0; i < num_test_cases; i++)
504 : : {
505 : 288 : for (int j = 0; j < num_test_cases; j++)
506 : : {
507 : 256 : edit_distance_t dist_ij
508 : 256 : = get_edit_distance (test_data[i], test_data[j]);
509 : :
510 : : /* Identity of indiscernibles: d(i, j) > 0 iff i == j. */
511 : 256 : if (i == j)
512 : 32 : ASSERT_EQ (dist_ij, 0);
513 : : else
514 : 224 : ASSERT_TRUE (dist_ij > 0);
515 : :
516 : : /* Symmetry: d(i, j) == d(j, i). */
517 : 256 : edit_distance_t dist_ji
518 : 256 : = get_edit_distance (test_data[j], test_data[i]);
519 : 256 : ASSERT_EQ (dist_ij, dist_ji);
520 : : }
521 : : }
522 : 4 : }
523 : :
524 : : /* Run all of the selftests within this file. */
525 : :
526 : : void
527 : 4 : spellcheck_cc_tests ()
528 : : {
529 : 4 : test_edit_distances ();
530 : 4 : test_get_edit_distance_cutoff ();
531 : 4 : test_suggestions ();
532 : 4 : test_find_closest_string ();
533 : 4 : test_metric_conditions ();
534 : 4 : }
535 : :
536 : : } // namespace selftest
537 : :
538 : : #endif /* #if CHECKING_P */
|
