[Emacs-diffs] master 1a50945: Improve [:alpha:] and [:alnum:] for multibyte characters (Bug#19878)

[Eli Zaretskii]

branch: master
commit 1a50945fa4c666ae2ab5cd9419d23ad063ea1249
Author: Eli Zaretskii <address@hidden>
Commit: Eli Zaretskii <address@hidden>

    Improve [:alpha:] and [:alnum:] for multibyte characters  (Bug#19878)
    
     src/character.c (alphabeticp, decimalnump): New functions.
     src/character.h (alphabeticp, decimalnump): Add prototypes.
     src/regex.c (ISALNUM, ISALPHA): Check Unicode character properties
     for multibyte characters by calling alphabeticp and decimalnump.
     (BIT_ALPHA, BIT_ALNUM): New bit masks.
     (re_wctype_to_bit): Return them when the class is RECC_ALPHA or
     RECC_ALNUM.
     (re_match_2_internal): Call ISALPHA and ISALNUM when appropriate.
    
     doc/lispref/searching.texi (Char Classes): Update the documentation of
     [:alpha:] and [:alnum:].
    
     etc/NEWS: Mention the changes in [:alpha:] and [:alnum:].
---
 doc/lispref/ChangeLog      |    5 +++++
 doc/lispref/searching.texi |   12 ++++++++----
 etc/NEWS                   |    6 ++++++
 src/ChangeLog              |   13 +++++++++++++
 src/character.c            |   42 ++++++++++++++++++++++++++++++++++++++++++
 src/character.h            |    3 +++
 src/regex.c                |   18 ++++++++++++------
 7 files changed, 89 insertions(+), 10 deletions(-)

diff --git a/doc/lispref/ChangeLog b/doc/lispref/ChangeLog
index bff469a..78f7e34 100644
--- a/doc/lispref/ChangeLog
+++ b/doc/lispref/ChangeLog
@@ -1,3 +1,8 @@
+2015-02-28  Eli Zaretskii  <address@hidden>
+
+       * searching.texi (Char Classes): Update the documentation of
+       [:alpha:] and [:alnum:].  (Bug#19878)
+
 2015-02-27  Eli Zaretskii  <address@hidden>
 
        * os.texi (Startup Summary):
diff --git a/doc/lispref/searching.texi b/doc/lispref/searching.texi
index 61fac78..87513e8 100644
--- a/doc/lispref/searching.texi
+++ b/doc/lispref/searching.texi
@@ -541,11 +541,15 @@ and what they mean:
 @item [:ascii:]
 This matches any @acronym{ASCII} character (codes 0--127).
 @item [:alnum:]
-This matches any letter or digit.  (At present, for multibyte
-characters, it matches anything that has word syntax.)
+This matches any letter or digit.  For multibyte characters, it
+matches characters whose Unicode @samp{general-category} property
+(@pxref{Character Properties}) indicates they are alphabetic or
+decimal number characters.
 @item [:alpha:]
-This matches any letter.  (At present, for multibyte characters, it
-matches anything that has word syntax.)
+This matches any letter.  For multibyte characters, it matches
+characters whose Unicode @samp{general-category} property
+(@pxref{Character Properties}) indicates they are alphabetic
+characters.
 @item [:blank:]
 This matches space and tab only.
 @item [:cntrl:]
diff --git a/etc/NEWS b/etc/NEWS
index d5cb947..3be820e 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -612,6 +612,12 @@ when signaling a file error.  For example, it now reports 
"Permission
 denied" instead of "permission denied".  The old behavior was problematic
 in languages like German where downcasing rules depend on grammar.
 
++++
+** The character classes [:alpha:] and [:alnum:] in regular expressions
+now match multibyte characters using Unicode character properties.
+If you want the old behavior where they matched any character with
+word syntax, use `\sw' instead.
+
 
 * Lisp Changes in Emacs 25.1
 
diff --git a/src/ChangeLog b/src/ChangeLog
index df68791..97ecbac 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,16 @@
+2015-02-28  Eli Zaretskii  <address@hidden>
+
+       * character.c (alphabeticp, decimalnump): New functions.
+       * character.h (alphabeticp, decimalnump): Add prototypes.
+
+       * regex.c (ISALNUM, ISALPHA): Check Unicode character properties
+       for multibyte characters by calling alphabeticp and decimalnump.
+       (BIT_ALPHA, BIT_ALNUM): New bit masks.
+       (re_wctype_to_bit): Return them when the class is RECC_ALPHA or
+       RECC_ALNUM.
+       (re_match_2_internal): Call ISALPHA and ISALNUM when appropriate.
+       (Bug#19878)
+
 2015-02-27  Jan Djärv  <address@hidden>
 
        * xterm.h (x_real_pos_and_offsets): Take outer_border as arg also.
diff --git a/src/character.c b/src/character.c
index 39d32c9..999f99a 100644
--- a/src/character.c
+++ b/src/character.c
@@ -984,6 +984,48 @@ character is not ASCII nor 8-bit character, an error is 
signaled.  */)
 
 #ifdef emacs
 
+/* Return 'true' if C is an alphabetic character as defined by its
+   Unicode properties.  */
+bool
+alphabeticp (int c)
+{
+  Lisp_Object category = CHAR_TABLE_REF (Vunicode_category_table, c);
+
+  if (INTEGERP (category))
+    {
+      unicode_category_t gen_cat = XINT (category);
+
+      /* See UTS #18.  There are additional characters that should be
+        here, those designated as Other_uppercase, Other_lowercase,
+        and Other_alphabetic; FIXME.  */
+      return (gen_cat == UNICODE_CATEGORY_Lu
+             || gen_cat == UNICODE_CATEGORY_Ll
+             || gen_cat == UNICODE_CATEGORY_Lt
+             || gen_cat == UNICODE_CATEGORY_Lm
+             || gen_cat == UNICODE_CATEGORY_Lo
+             || gen_cat == UNICODE_CATEGORY_Mn
+             || gen_cat == UNICODE_CATEGORY_Mc
+             || gen_cat == UNICODE_CATEGORY_Me
+             || gen_cat == UNICODE_CATEGORY_Nl) ? true : false;
+    }
+}
+
+/* Return 'true' if C is an decimal-number character as defined by its
+   Unicode properties.  */
+bool
+decimalnump (int c)
+{
+  Lisp_Object category = CHAR_TABLE_REF (Vunicode_category_table, c);
+
+  if (INTEGERP (category))
+    {
+      unicode_category_t gen_cat = XINT (category);
+
+      /* See UTS #18.  */
+      return (gen_cat == UNICODE_CATEGORY_Nd) ? true : false;
+    }
+}
+
 void
 syms_of_character (void)
 {
diff --git a/src/character.h b/src/character.h
index 5043880..7d90295 100644
--- a/src/character.h
+++ b/src/character.h
@@ -660,6 +660,9 @@ extern ptrdiff_t lisp_string_width (Lisp_Object, ptrdiff_t,
 extern Lisp_Object Vchar_unify_table;
 extern Lisp_Object string_escape_byte8 (Lisp_Object);
 
+extern bool alphabeticp (int);
+extern bool decimalnump (int);
+
 /* Return a translation table of id number ID.  */
 #define GET_TRANSLATION_TABLE(id) \
   (XCDR (XVECTOR (Vtranslation_table_vector)->contents[(id)]))
diff --git a/src/regex.c b/src/regex.c
index 41fe3fa..1afc503 100644
--- a/src/regex.c
+++ b/src/regex.c
@@ -324,12 +324,12 @@ enum syntaxcode { Swhitespace = 0, Sword = 1, Ssymbol = 2 
};
                    ? (((c) >= 'a' && (c) <= 'z')       \
                       || ((c) >= 'A' && (c) <= 'Z')    \
                       || ((c) >= '0' && (c) <= '9'))   \
-                   : SYNTAX (c) == Sword)
+                   : (alphabeticp (c) || decimalnump (c)))
 
 # define ISALPHA(c) (IS_REAL_ASCII (c)                 \
                    ? (((c) >= 'a' && (c) <= 'z')       \
                       || ((c) >= 'A' && (c) <= 'Z'))   \
-                   : SYNTAX (c) == Sword)
+                   : alphabeticp (c))
 
 # define ISLOWER(c) lowercasep (c)
 
@@ -1872,6 +1872,8 @@ struct range_table_work_area
 #define BIT_SPACE      0x8
 #define BIT_UPPER      0x10
 #define BIT_MULTIBYTE  0x20
+#define BIT_ALPHA      0x40
+#define BIT_ALNUM      0x80
 
 
 /* Set the bit for character C in a list.  */
@@ -2072,7 +2074,9 @@ re_wctype_to_bit (re_wctype_t cc)
     {
     case RECC_NONASCII: case RECC_PRINT: case RECC_GRAPH:
     case RECC_MULTIBYTE: return BIT_MULTIBYTE;
-    case RECC_ALPHA: case RECC_ALNUM: case RECC_WORD: return BIT_WORD;
+    case RECC_ALPHA: return BIT_ALPHA;
+    case RECC_ALNUM: return BIT_ALNUM;
+    case RECC_WORD: return BIT_WORD;
     case RECC_LOWER: return BIT_LOWER;
     case RECC_UPPER: return BIT_UPPER;
     case RECC_PUNCT: return BIT_PUNCT;
@@ -2930,7 +2934,7 @@ regex_compile (const_re_char *pattern, size_t size, 
reg_syntax_t syntax,
 #endif /* emacs */
                        /* In most cases the matching rule for char classes
                           only uses the syntax table for multibyte chars,
-                          so that the content of the syntax-table it is not
+                          so that the content of the syntax-table is not
                           hardcoded in the range_table.  SPACE and WORD are
                           the two exceptions.  */
                        if ((1 << cc) & ((1 << RECC_SPACE) | (1 << RECC_WORD)))
@@ -2945,7 +2949,7 @@ regex_compile (const_re_char *pattern, size_t size, 
reg_syntax_t syntax,
                        p = class_beg;
                        SET_LIST_BIT ('[');
 
-                       /* Because the `:' may starts the range, we
+                       /* Because the `:' may start the range, we
                           can't simply set bit and repeat the loop.
                           Instead, just set it to C and handle below.  */
                        c = ':';
@@ -5513,7 +5517,9 @@ re_match_2_internal (struct re_pattern_buffer *bufp, 
const_re_char *string1,
                    | (class_bits & BIT_PUNCT && ISPUNCT (c))
                    | (class_bits & BIT_SPACE && ISSPACE (c))
                    | (class_bits & BIT_UPPER && ISUPPER (c))
-                   | (class_bits & BIT_WORD  && ISWORD (c)))
+                   | (class_bits & BIT_WORD  && ISWORD  (c))
+                   | (class_bits & BIT_ALPHA && ISALPHA (c))
+                   | (class_bits & BIT_ALNUM && ISALNUM (c)))
                  not = !not;
                else
                  CHARSET_LOOKUP_RANGE_TABLE_RAW (not, c, range_table, count);