(dabbrev-case-distinction): New option.

(dabbrev--try-find): Handle dabbrev-case-distinction.
(dabbrev--search): Clean up the code.
(dabbrev-upcase-means-case-search): Doc fix.
(dabbrev-case-replace): Fix custom tags and docs.

2 files changed, 46 insertions, 19 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 94e145e7b91..87ae381fe96 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,11 @@
+2002-05-14  Richard M. Stallman  <rms@gnu.org>
+
+        * dabbrev.el (dabbrev-case-distinction): New option.
+        (dabbrev--try-find): Handle dabbrev-case-distinction.
+        (dabbrev--search): Clean up the code.
+        (dabbrev-upcase-means-case-search): Doc fix.
+        (dabbrev-case-replace): Fix custom tags and docs.
+
 2002-05-14  Jochen K,A|(Bpper  <jochen@jochen-kuepper.de>
 
         * calc/calc-units.el (math-standard-units): Update from CODATA.
diff --git a/lisp/dabbrev.el b/lisp/dabbrev.el
index 55b080ee0b1..f2beb011247 100644
--- a/lisp/dabbrev.el
+++ b/lisp/dabbrev.el
@@ -147,23 +147,41 @@ Any other non-nil version means case is not significant."
 
 (defcustom dabbrev-upcase-means-case-search nil
   "*The significance of an uppercase character in an abbreviation.
-nil means case fold search, non-nil means case sensitive search.
+nil means case fold search when searching for possible expansions;
+non-nil means case sensitive search.
 
 This variable has an effect only when the value of
 `dabbrev-case-fold-search' says to ignore case."
   :type 'boolean
   :group 'dabbrev)
 
+(defcustom dabbrev-case-distinction 'case-replace
+  "*Whether dabbrev treats expansions as the same if they differ in case.
+
+A value of nil means treat them as different.
+A value of `case-replace' means distinguish them if `case-replace' is nil.
+Any other non-nil value means to treat them as the same.
+
+This variable has an effect only when the value of
+`dabbrev-case-fold-search' specifies to ignore case."
+  :type '(choice (const :tag "off" nil)
+                 (const :tag "based on `case-replace'" case-replace)
+                 (other :tag "on" t))
+  :group 'dabbrev
+  :version "21.4")
+
 (defcustom dabbrev-case-replace 'case-replace
-  "*Controls whether dabbrev preserves case when expanding the abbreviation.
-A value of nil means preserve case.
-A value of `case-replace' means preserve case if `case-replace' is nil.
-Any other non-nil version means do not preserve case.
+  "*Whether dabbrev applies the abbreviations's case pattern to the expansion.
+
+A value of nil means preserve the expansion's case pattern.
+A value of `case-replace' means preserve it if `case-replace' is nil.
+Any other non-nil value means modify the expansion
+by applying the abbreviation's case pattern to it.
 
 This variable has an effect only when the value of
 `dabbrev-case-fold-search' specifies to ignore case."
   :type '(choice (const :tag "off" nil)
-                 (const :tag "like M-x query-replace" case-replace)
+                 (const :tag "based on `case-replace'" case-replace)
                  (other :tag "on" t))
   :group 'dabbrev)
 
@@ -689,7 +707,11 @@ of the expansion in `dabbrev--last-expansion-location'."
           (while (and (> count 0)
                       (setq expansion (dabbrev--search abbrev
                                                        reverse
-                                                       ignore-case)))
+                                                       (and ignore-case
+                                                            (if (eq dabbrev-case-distinction 'case-replace)
+                                                                case-replace
+                                                              dabbrev-case-distinction))
+                                                       )))
             (setq count (1- count))))
         (and expansion
              (setq dabbrev--last-expansion-location (point)))
@@ -950,7 +972,7 @@ Leaves point at the location of the start of the expansion."
                             "\\(" dabbrev--abbrev-char-regexp "\\)"))
           (pattern2 (concat (regexp-quote abbrev)
                            "\\(\\(" dabbrev--abbrev-char-regexp "\\)+\\)"))
-          (found-string nil))
+          found-string result)
       ;; Limited search.
       (save-restriction
         (and dabbrev-limit
@@ -974,7 +996,8 @@ Leaves point at the location of the start of the expansion."
             ;; We have a truly valid match.  Find the end.
             (re-search-forward pattern2)
             (setq found-string (buffer-substring-no-properties
-                                (match-beginning 1) (match-end 1)))
+                                (match-beginning 0) (match-end 0)))
+            (setq result found-string)
             (and ignore-case (setq found-string (downcase found-string)))
             ;; Ignore this match if it's already in the table.
             (if (dabbrev-filter-elements
@@ -986,16 +1009,12 @@ Leaves point at the location of the start of the expansion."
               (goto-char (match-beginning 0))
             (goto-char (match-end 0))))
         ;; If we found something, use it.
-        (if found-string
-            ;; Put it into `dabbrev--last-table'
-            ;; and return it (either downcased, or as is).
-            (let ((result (buffer-substring-no-properties
-                           (match-beginning 0) (match-end 0))))
-              (setq dabbrev--last-table
-                    (cons found-string dabbrev--last-table))
-              (if (and ignore-case (eval dabbrev-case-replace))
-                  result
-                result)))))))
+        (when found-string
+          ;; Put it into `dabbrev--last-table'
+          ;; and return it (either downcased, or as is).
+          (setq dabbrev--last-table
+                (cons found-string dabbrev--last-table))
+          result)))))
 
 (dolist (mess '("^No dynamic expansion for .* found$"
                 "^No further dynamic expansion for .* found$"