[Nano-devel] [PATCH] new feature: the option --wordchars, to set extra word characters

[Benno Schulenberg]

This allows the user to specify which other characters, besides the
default alphanumeric ones, should be considered as part of a word, so
that word operations like Ctrl+Left and Ctrl+Right will pass them by.

Using this option overrides the option --wordbounds.

This fulfills https://savannah.gnu.org/bugs/?47283.
---
 src/chars.c  | 15 +++++++++++++--
 src/global.c |  4 ++++
 src/nano.c   | 20 ++++++++++++++++++--
 src/proto.h  |  3 +++
 src/rcfile.c |  4 ++++
 src/utils.c  |  4 ++--
 6 files changed, 44 insertions(+), 6 deletions(-)

diff --git a/src/chars.c b/src/chars.c
index d36faae..f66d62e 100644
--- a/src/chars.c
+++ b/src/chars.c
@@ -192,8 +192,19 @@ bool is_word_mbchar(const char *c, bool allow_punct)
 {
     assert(c != NULL);
 
-    return is_alnum_mbchar(c) || (allow_punct ? is_punct_mbchar(c) :
-       FALSE);
+    if (is_alnum_mbchar(c))
+       return TRUE;
+
+    if (word_chars != NULL) {
+       char *symbol = charalloc(MB_CUR_MAX + 1);
+       int symlen = parse_mbchar(c, symbol, NULL);
+
+       symbol[symlen] = '\0';
+
+       return (strstr(word_chars, symbol) != NULL);
+    }
+
+    return (allow_punct ? is_punct_mbchar(c) : FALSE);
 }
 
 /* Return the visible representation of control character c. */
diff --git a/src/global.c b/src/global.c
index fb8cce2..2ab9188 100644
--- a/src/global.c
+++ b/src/global.c
@@ -124,6 +124,9 @@ size_t quotelen;
 #endif
 #endif
 
+char *word_chars = NULL;
+       /* Nonalphanumeric characters that also form words. */
+
 bool nodelay_mode = FALSE;
        /* Are we checking for a cancel wile doing something? */
 
@@ -1669,6 +1672,7 @@ void thanks_for_all_the_fish(void)
     delwin(edit);
     delwin(bottomwin);
 
+    free(word_chars);
 #ifndef DISABLE_JUSTIFY
     free(quotestr);
 #ifdef HAVE_REGEX_H
diff --git a/src/nano.c b/src/nano.c
index 367d3f3..978ded0 100644
--- a/src/nano.c
+++ b/src/nano.c
@@ -860,6 +860,8 @@ void usage(void)
 #ifndef NANO_TINY
     print_opt("-W", "--wordbounds",
        N_("Detect word boundaries more accurately"));
+    print_opt("-X", "--wordchars",
+       N_("Which other characters are word parts"));
 #endif
 #ifndef DISABLE_COLOR
     if (!ISSET(RESTRICTED))
@@ -1995,6 +1997,7 @@ int main(int argc, char **argv)
        {"smooth", 0, NULL, 'S'},
        {"quickblank", 0, NULL, 'U'},
        {"wordbounds", 0, NULL, 'W'},
+       {"wordchars", 1, NULL, 'X'},
        {"autoindent", 0, NULL, 'i'},
        {"cut", 0, NULL, 'k'},
        {"unix", 0, NULL, 'u'},
@@ -2040,11 +2043,11 @@ int main(int argc, char **argv)
     while ((optchr =
 #ifdef HAVE_GETOPT_LONG
        getopt_long(argc, argv,
-               "ABC:DEFGHIKLNOPQ:RST:UVWY:abcdefghijklmno:pqr:s:tuvwxz$",
+               "ABC:DEFGHIKLNOPQ:RST:UVWX:Y:abcdefghijklmno:pqr:s:tuvwxz$",
                long_options, NULL)
 #else
        getopt(argc, argv,
-               "ABC:DEFGHIKLNOPQ:RST:UVWY:abcdefghijklmno:pqr:s:tuvwxz$")
+               "ABC:DEFGHIKLNOPQ:RST:UVWX:Y:abcdefghijklmno:pqr:s:tuvwxz$")
 #endif
                ) != -1) {
        switch (optchr) {
@@ -2146,6 +2149,9 @@ int main(int argc, char **argv)
            case 'W':
                SET(WORD_BOUNDS);
                break;
+           case 'X':
+               word_chars = mallocstrcpy(word_chars, optarg);
+               break;
 #endif
 #ifndef DISABLE_COLOR
            case 'Y':
@@ -2279,6 +2285,7 @@ int main(int argc, char **argv)
 #endif
 #ifndef NANO_TINY
        char *backup_dir_cpy = backup_dir;
+       char *word_chars_cpy = word_chars;
 #endif
 #ifndef DISABLE_JUSTIFY
        char *quotestr_cpy = quotestr;
@@ -2297,6 +2304,7 @@ int main(int argc, char **argv)
 #endif
 #ifndef NANO_TINY
        backup_dir = NULL;
+       word_chars = NULL;
 #endif
 #ifndef DISABLE_JUSTIFY
        quotestr = NULL;
@@ -2327,6 +2335,10 @@ int main(int argc, char **argv)
            free(backup_dir);
            backup_dir = backup_dir_cpy;
        }
+       if (word_chars_cpy != NULL) {
+           free(word_chars);
+           word_chars = word_chars_cpy;
+       }
 #endif
 #ifndef DISABLE_JUSTIFY
        if (quotestr_cpy != NULL) {
@@ -2391,6 +2403,10 @@ int main(int argc, char **argv)
      * that backup files will be saved there. */
     if (!ISSET(RESTRICTED))
        init_backup_dir();
+
+    /* By default, nothing but alphanumeric characters form words. */
+    if (word_chars == NULL)
+       word_chars = mallocstrcpy(NULL, "");
 #endif
 
 #ifndef DISABLE_OPERATINGDIR
diff --git a/src/proto.h b/src/proto.h
index c3386af..e959b13 100644
--- a/src/proto.h
+++ b/src/proto.h
@@ -91,7 +91,10 @@ extern size_t quotelen;
 #endif
 #endif /* !DISABLE_JUSTIFY */
 
+extern char *word_chars;
+
 extern bool nodelay_mode;
+
 extern char *answer;
 
 extern ssize_t tabsize;
diff --git a/src/rcfile.c b/src/rcfile.c
index 8face04..f35a3d8 100644
--- a/src/rcfile.c
+++ b/src/rcfile.c
@@ -102,6 +102,7 @@ static const rcoption rcopts[] = {
     {"unix", MAKE_IT_UNIX},
     {"whitespace", 0},
     {"wordbounds", WORD_BOUNDS},
+    {"wordchars", 0},
 #endif
 #ifndef DISABLE_COLOR
     {"titlecolor", 0},
@@ -1176,6 +1177,9 @@ void parse_rcfile(FILE *rcstream
        if (strcasecmp(rcopts[i].name, "backupdir") == 0)
            backup_dir = option;
        else
+       if (strcasecmp(rcopts[i].name, "wordchars") == 0)
+           word_chars = option;
+       else
 #endif
 #ifndef DISABLE_SPELLER
        if (strcasecmp(rcopts[i].name, "speller") == 0)
diff --git a/src/utils.c b/src/utils.c
index 4411499..25294ff 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -296,8 +296,8 @@ bool is_separate_word(size_t position, size_t length, const 
char *buf)
      * word isn't a non-punctuation "word" character, and if we're at
      * the end of the line or the character after the word isn't a
      * non-punctuation "word" character, we have a whole word. */
-    retval = (position == 0 || !is_word_mbchar(before, FALSE)) &&
-               (word_end == strlen(buf) || !is_word_mbchar(after, FALSE));
+    retval = (position == 0 || !is_alnum_mbchar(before)) &&
+               (word_end == strlen(buf) || !is_alnum_mbchar(after));
 
     free(before);
     free(after);
-- 
2.8.4