#include "spellcheck.h"
#include "selftest.h"
+/* Cost of a case transformation. */
+#define CASE_COST 1
+
+/* Cost of another kind of edit. */
+#define BASE_COST 2
+
/* Get the edit distance between the two strings: the minimal
number of edits that are needed to change one string into another,
where edits can be one-character insertions, removals, or substitutions,
or transpositions of two adjacent characters (counting as one "edit").
- This implementation uses the Wagner-Fischer algorithm for the
- Damerau-Levenshtein distance; specifically, the "optimal string alignment
- distance" or "restricted edit distance" variant. */
+ This implementation uses a modified variant of the Wagner-Fischer
+ algorithm for the Damerau-Levenshtein distance; specifically, the
+ "optimal string alignment distance" or "restricted edit distance"
+ variant. This implementation has been further modified to take
+ case into account. */
edit_distance_t
get_edit_distance (const char *s, int len_s,
}
if (len_s == 0)
- return len_t;
+ return BASE_COST * len_t;
if (len_t == 0)
- return len_s;
+ return BASE_COST * len_s;
/* We effectively build a matrix where each (i, j) contains the
distance between the prefix strings s[0:j] and t[0:i].
/* The first row is for the case of an empty target string, which
we can reach by deleting every character in the source string. */
for (int i = 0; i < len_s + 1; i++)
- v_one_ago[i] = i;
+ v_one_ago[i] = i * BASE_COST;
/* Build successive rows. */
for (int i = 0; i < len_t; i++)
/* The initial column is for the case of an empty source string; we
can reach prefixes of the target string of length i
by inserting i characters. */
- v_next[0] = i + 1;
+ v_next[0] = (i + 1) * BASE_COST;
/* Build the rest of the row by considering neighbors to
the north, west and northwest. */
for (int j = 0; j < len_s; j++)
{
- edit_distance_t cost = (s[j] == t[i] ? 0 : 1);
- edit_distance_t deletion = v_next[j] + 1;
- edit_distance_t insertion = v_one_ago[j + 1] + 1;
+ edit_distance_t cost;
+
+ if (s[j] == t[i])
+ cost = 0;
+ else if (TOLOWER (s[j]) == TOLOWER (t[i]))
+ cost = CASE_COST;
+ else
+ cost = BASE_COST;
+ edit_distance_t deletion = v_next[j] + BASE_COST;
+ edit_distance_t insertion = v_one_ago[j + 1] + BASE_COST;
edit_distance_t substitution = v_one_ago[j] + cost;
edit_distance_t cheapest = MIN (deletion, insertion);
cheapest = MIN (cheapest, substitution);
if (i > 0 && j > 0 && s[j] == t[i - 1] && s[j - 1] == t[i])
{
- edit_distance_t transposition = v_two_ago[j - 1] + 1;
+ edit_distance_t transposition = v_two_ago[j - 1] + BASE_COST;
cheapest = MIN (cheapest, transposition);
}
v_next[j + 1] = cheapest;
/* If the lengths are close, then round down. */
if (max_length - min_length <= 1)
/* ...but allow an edit distance of at least 1. */
- return MAX (max_length / 3, 1);
+ return BASE_COST * MAX (max_length / 3, 1);
/* Otherwise, round up (thus giving a little extra leeway to some cases
involving insertions/deletions). */
- return (max_length + 2) / 3;
+ return BASE_COST * (max_length + 2) / 3;
}
#if CHECKING_P
static void
test_edit_distances ()
{
- test_get_edit_distance_both_ways ("", "nonempty", strlen ("nonempty"));
- test_get_edit_distance_both_ways ("saturday", "sunday", 3);
- test_get_edit_distance_both_ways ("foo", "m_foo", 2);
- test_get_edit_distance_both_ways ("hello_world", "HelloWorld", 3);
+ test_get_edit_distance_both_ways ("", "nonempty",
+ BASE_COST * strlen ("nonempty"));
+ test_get_edit_distance_both_ways ("saturday", "sunday",
+ BASE_COST * 3);
+ test_get_edit_distance_both_ways ("foo", "m_foo", BASE_COST * 2);
+ test_get_edit_distance_both_ways ("hello_world", "HelloWorld", 4);
test_get_edit_distance_both_ways
- ("the quick brown fox jumps over the lazy dog", "dog", 40);
+ ("the quick brown fox jumps over the lazy dog", "dog", BASE_COST * 40);
test_get_edit_distance_both_ways
("the quick brown fox jumps over the lazy dog",
"the quick brown dog jumps over the lazy fox",
- 4);
+ BASE_COST * 4);
test_get_edit_distance_both_ways
("Lorem ipsum dolor sit amet, consectetur adipiscing elit,",
"All your base are belong to us",
- 44);
+ BASE_COST * 44);
test_get_edit_distance_both_ways ("foo", "FOO", 3);
- test_get_edit_distance_both_ways ("fee", "deed", 2);
- test_get_edit_distance_both_ways ("coorzd1", "coordx1", 2);
- test_get_edit_distance_both_ways ("assert", "sqrt", 3);
- test_get_edit_distance_both_ways ("PATH_MAX", "INT8_MAX", 3);
- test_get_edit_distance_both_ways ("time", "nice", 2);
- test_get_edit_distance_both_ways ("bar", "carg", 2);
+ test_get_edit_distance_both_ways ("fee", "deed", BASE_COST * 2);
+ test_get_edit_distance_both_ways ("coorzd1", "coordx1", BASE_COST * 2);
+ test_get_edit_distance_both_ways ("assert", "sqrt", BASE_COST * 3);
+ test_get_edit_distance_both_ways ("PATH_MAX", "INT8_MAX", BASE_COST * 3);
+ test_get_edit_distance_both_ways ("time", "nice", BASE_COST * 2);
+ test_get_edit_distance_both_ways ("bar", "carg", BASE_COST * 2);
test_get_edit_distance_both_ways ("gtk_widget_show_all",
- "GtkWidgetShowAll", 7);
- test_get_edit_distance_both_ways ("m_bar", "bar", 2);
- test_get_edit_distance_both_ways ("MACRO", "MACRAME", 3);
- test_get_edit_distance_both_ways ("ab", "ac", 1);
- test_get_edit_distance_both_ways ("ab", "a", 1);
- test_get_edit_distance_both_ways ("a", "b", 1);
- test_get_edit_distance_both_ways ("nanl", "name", 2);
- test_get_edit_distance_both_ways ("char", "bar", 2);
- test_get_edit_distance_both_ways ("-optimize", "fsanitize", 5);
- test_get_edit_distance_both_ways ("__DATE__", "__i386__", 4);
+ "GtkWidgetShowAll", 10);
+ test_get_edit_distance_both_ways ("m_bar", "bar", BASE_COST * 2);
+ test_get_edit_distance_both_ways ("MACRO", "MACRAME", BASE_COST * 3);
+ test_get_edit_distance_both_ways ("ab", "ac", BASE_COST * 1);
+ test_get_edit_distance_both_ways ("ab", "a", BASE_COST * 1);
+ test_get_edit_distance_both_ways ("a", "b", BASE_COST * 1);
+ test_get_edit_distance_both_ways ("nanl", "name", BASE_COST * 2);
+ test_get_edit_distance_both_ways ("char", "bar", BASE_COST * 2);
+ test_get_edit_distance_both_ways ("-optimize", "fsanitize", BASE_COST * 5);
+ test_get_edit_distance_both_ways ("__DATE__", "__i386__", BASE_COST * 4);
/* Examples where transposition helps. */
- test_get_edit_distance_both_ways ("ab", "ba", 1);
- test_get_edit_distance_both_ways ("ba", "abc", 2);
- test_get_edit_distance_both_ways ("coorzd1", "coordz1", 1);
+ test_get_edit_distance_both_ways ("ab", "ba", BASE_COST * 1);
+ test_get_edit_distance_both_ways ("ba", "abc", BASE_COST * 2);
+ test_get_edit_distance_both_ways ("coorzd1", "coordz1", BASE_COST * 1);
test_get_edit_distance_both_ways ("abcdefghijklmnopqrstuvwxyz",
- "bacdefghijklmnopqrstuvwxzy", 2);
- test_get_edit_distance_both_ways ("saturday", "sundya", 4);
- test_get_edit_distance_both_ways ("signed", "singed", 1);
+ "bacdefghijklmnopqrstuvwxzy",
+ BASE_COST * 2);
+ test_get_edit_distance_both_ways ("saturday", "sundya", BASE_COST * 4);
+ test_get_edit_distance_both_ways ("signed", "singed", BASE_COST * 1);
}
/* Subroutine of test_get_edit_distance_cutoff, for emulating the
static edit_distance_t
get_old_cutoff (size_t goal_len, size_t candidate_len)
{
- return MAX (goal_len, candidate_len) / 2;
+ return BASE_COST * MAX (goal_len, candidate_len) / 2;
}
/* Verify that the cutoff for "meaningfulness" of suggestions is at least as
candidates.safe_push("coordy1");
candidates.safe_push("coordz1");
ASSERT_STREQ ("coordz1", find_closest_string ("coorzd1", &candidates));
+
+ candidates.truncate (0);
+ candidates.safe_push ("DWARF_GNAT_ENCODINGS_GDB");
+ candidates.safe_push ("DWARF_GNAT_ENCODINGS_ALL");
+ candidates.safe_push ("DWARF_GNAT_ENCODINGS_MINIMAL");
+ ASSERT_STREQ ("DWARF_GNAT_ENCODINGS_ALL",
+ find_closest_string ("DWARF_GNAT_ENCODINGS_all",
+ &candidates));
+
+ /* The same as the previous test, but with a different order of
+ candidates. */
+ candidates.truncate (0);
+ candidates.safe_push ("DWARF_GNAT_ENCODINGS_ALL");
+ candidates.safe_push ("DWARF_GNAT_ENCODINGS_GDB");
+ candidates.safe_push ("DWARF_GNAT_ENCODINGS_MINIMAL");
+ ASSERT_STREQ ("DWARF_GNAT_ENCODINGS_ALL",
+ find_closest_string ("DWARF_GNAT_ENCODINGS_all",
+ &candidates));
}
/* Test data for test_metric_conditions. */
projects / gcc.git / commitdiff