patch 8.2.1921: fuzzy matching does not recognize path separators

Problem:    Fuzzy matching does not recognize path separators.
Solution:   Add a bonus for slash and backslash. (Yegappan Lakshmanan,
            closes #7225)

Author: brammool

src/search.c

@@ -4258,8 +4258,10 @@ typedef struct
 // bonus for adjacent matches; this is higher than SEPARATOR_BONUS so that
 // matching a whole word is preferred.
 #define SEQUENTIAL_BONUS 40
-// bonus if match occurs after a separator
-#define SEPARATOR_BONUS 30
+// bonus if match occurs after a path separator
+#define PATH_SEPARATOR_BONUS 30
+// bonus if match occurs after a word separator
+#define WORD_SEPARATOR_BONUS 25
 // bonus if match is uppercase and prev is lower
 #define CAMEL_BONUS 30
 // bonus if the first letter is matched
@@ -4334,7 +4336,6 @@ fuzzy_match_compute_score(
 	    // Camel case
 	    int	neighbor = ' ';
 	    int	curr;
-	    int	neighborSeparator;
 
 	    if (has_mbyte)
 	    {
@@ -4355,10 +4356,11 @@ fuzzy_match_compute_score(
 	    if (vim_islower(neighbor) && vim_isupper(curr))
 		score += CAMEL_BONUS;
 
-	    // Separator
-	    neighborSeparator = neighbor == '_' || neighbor == ' ';
-	    if (neighborSeparator)
-		score += SEPARATOR_BONUS;
+	    // Bonus if the match follows a separator character
+	    if (neighbor == '/' || neighbor == '\\')
+		score += PATH_SEPARATOR_BONUS;
+	    else if (neighbor == ' ' || neighbor == '_')
+		score += WORD_SEPARATOR_BONUS;
 	}
 	else
 	{

src/testdir/test_matchfuzzy.vim

@@ -43,6 +43,8 @@ func Test_matchfuzzy()
   call assert_equal(['.vim/vimrc', '.vim/vimrc_colors', '.vim/v_i_m_r_c'], ['.vim/vimrc', '.vim/vimrc_colors', '.vim/v_i_m_r_c']->matchfuzzy('vimrc'))
   " gap penalty
   call assert_equal(['xxayybxxxx', 'xxayyybxxx', 'xxayyyybxx'], ['xxayyyybxx', 'xxayyybxxx', 'xxayybxxxx']->matchfuzzy('ab'))
+  " path separator vs word separator
+  call assert_equal(['color/setup.vim', 'color\\setup.vim', 'color setup.vim', 'color_setup.vim', 'colorsetup.vim'], matchfuzzy(['colorsetup.vim', 'color setup.vim', 'color/setup.vim', 'color_setup.vim', 'color\\setup.vim'], 'setup.vim'))
 
   " match multiple words (separated by space)
   call assert_equal(['foo bar baz'], ['foo bar baz', 'foo', 'foo bar', 'baz bar']->matchfuzzy('baz foo'))

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1921,
 /**/
     1920,
 /**/