[Emacs-diffs] trunk r117798: Implement the GNU ls -v switch in ls-lisp.el.

[Eli Zaretskii]

------------------------------------------------------------
revno: 117798
revision-id: address@hidden
parent: address@hidden
fixes bug: http://debbugs.gnu.org/18051
committer: Eli Zaretskii <address@hidden>
branch nick: trunk
timestamp: Mon 2014-09-01 18:03:45 +0300
message:
  Implement the GNU ls -v switch in ls-lisp.el.
  
   lisp/ls-lisp.el (ls-lisp-version-lessp): New function.
   (ls-lisp-handle-switches): Use it to implement the -v switch of GNU ls.
   (ls-lisp--insert-directory): Mention the -v switch in the doc string.
modified:
  lisp/ChangeLog                 changelog-20091113204419-o5vbwnq5f7feedwu-1432
  lisp/ls-lisp.el                lslisp.el-20091113204419-o5vbwnq5f7feedwu-191

=== modified file 'lisp/ChangeLog'
--- a/lisp/ChangeLog    2014-09-01 14:57:21 +0000
+++ b/lisp/ChangeLog    2014-09-01 15:03:45 +0000
@@ -4,6 +4,11 @@
        (ls-lisp-UCA-like-collation): New defcustoms.
        (ls-lisp-string-lessp): Use them to control sorting by file
        names.  (Bug#18051)
+       (ls-lisp-version-lessp): New function.
+       (ls-lisp-handle-switches): Use it to implement the -v switch of
+       GNU ls.
+       (ls-lisp--insert-directory): Mention the -v switch in the doc
+       string.
 
 2014-08-31  Christoph Scholtes  <address@hidden>
 

=== modified file 'lisp/ls-lisp.el'
--- a/lisp/ls-lisp.el   2014-09-01 14:57:21 +0000
+++ b/lisp/ls-lisp.el   2014-09-01 15:03:45 +0000
@@ -273,7 +273,7 @@
 supports ordinary shell wildcards if `ls-lisp-support-shell-wildcards'
 is non-nil; otherwise, it interprets wildcards as regular expressions
 to match file names.  It does not support all `ls' switches -- those
-that work are: A a B C c F G g h i n R r S s t U u X.  The l switch
+that work are: A a B C c F G g h i n R r S s t U u v X.  The l switch
 is assumed to be always present and cannot be turned off."
   (if ls-lisp-use-insert-directory-program
       (funcall orig-fun
@@ -551,6 +551,67 @@
       (let ((u (compare-strings s1 0 nil s2 0 nil ls-lisp-ignore-case)))
        (and (numberp u) (< u 0))))))
 
+(defun ls-lisp-version-lessp (s1 s2)
+  "Return t if versioned string S1 should sort before versioned string S2.
+
+Case is significant if `ls-lisp-ignore-case' is nil.
+This is the same as string-lessp (with the exception of case
+insensitivity), but sequences of digits are compared numerically,
+as a whole, in the same manner as the `strverscmp' function available
+in some standard C libraries does."
+  (let ((i1 0)
+       (i2 0)
+       (len1 (length s1))
+       (len2 (length s2))
+       (val 0)
+       ni1 ni2 e1 e2 found-2-numbers-p)
+    (while (and (< i1 len1) (< i2 len2) (zerop val))
+      (unless found-2-numbers-p
+       (setq ni1 (string-match "[0-9]+" s1 i1)
+             e1 (match-end 0))
+       (setq ni2 (string-match "[0-9]+" s2 i2)
+             e2 (match-end 0)))
+      (cond
+       ((and ni1 ni2)
+       (cond
+        ((and (> ni1 i1) (> ni2 i2))
+         ;; Compare non-numerical part as strings.
+         (setq val (compare-strings s1 i1 ni1 s2 i2 ni2 ls-lisp-ignore-case)
+               i1 ni1
+               i2 ni2
+               found-2-numbers-p t))
+        ((and (= ni1 i1) (= ni2 i2))
+         (setq found-2-numbers-p nil)
+         ;; Compare numerical parts as integral and/or fractional parts.
+         (let* ((sub1 (substring s1 ni1 e1))
+                (sub2 (substring s2 ni2 e2))
+                ;; "Fraction" is a numerical sequence with leading zeros.
+                (fr1 (string-match "\\`0+" sub1))
+                (fr2 (string-match "\\`0+" sub2)))
+           (cond
+            ((and fr1 fr2)     ; two fractions, the shortest wins
+             (setq val (- val (- (length sub1) (length sub2)))))
+            (fr1               ; a fraction is always less than an integral
+             (setq val (- ni1)))
+            (fr2
+             (setq val ni2)))
+           (if (zerop val)     ; fall back on numerical comparison
+               (setq val (- (string-to-number sub1)
+                            (string-to-number sub2))))
+           (setq i1 e1
+                 i2 e2)))
+        (t
+         (setq val (compare-strings s1 i1 nil s2 i2 nil ls-lisp-ignore-case)
+               i1 len1
+               i2 len2))))
+       (t (setq val (compare-strings s1 i1 nil s2 i2 nil ls-lisp-ignore-case)
+               i1 len1
+               i2 len2)))
+      (and (eq val t) (setq val 0)))
+    (if (zerop val)
+       (setq val (- len1 len2)))
+    (< val 0)))
+
 (defun ls-lisp-handle-switches (file-alist switches)
   "Return new FILE-ALIST sorted according to SWITCHES.
 SWITCHES is a list of characters.  Default sorting is alphabetic."
@@ -577,6 +638,9 @@
                                 (ls-lisp-string-lessp
                                  (ls-lisp-extension (car x))
                                  (ls-lisp-extension (car y)))))
+                             ((memq ?v switches)
+                              (lambda (x y) ; sorted by version number
+                                (ls-lisp-version-lessp (car x) (car y))))
                              (t
                               (lambda (x y) ; sorted alphabetically
                                 (ls-lisp-string-lessp (car x) (car y))))))))