(pcomplete-unquote-argument-function): New var.

(pcomplete-unquote-argument): New function.
(pcomplete--common-suffix): Always pay attention to case.
(pcomplete--table-subvert): Quote and unquote the text.
(pcomplete--common-quoted-suffix): New function.
(pcomplete-std-complete): Use it and pcomplete-begin.

2 files changed, 189 insertions, 148 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index c6a8287942c..0ff59e4ef35 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,5 +1,12 @@
 2009-10-25  Stefan Monnier  <monnier@iro.umontreal.ca>
 
+        * pcomplete.el (pcomplete-unquote-argument-function): New var.
+        (pcomplete-unquote-argument): New function.
+        (pcomplete--common-suffix): Always pay attention to case.
+        (pcomplete--table-subvert): Quote and unquote the text.
+        (pcomplete--common-quoted-suffix): New function.
+        (pcomplete-std-complete): Use it and pcomplete-begin.
+
         * bookmark.el (bookmark-bmenu-list): Don't use switch-to-buffer if
         we're inside a dedicated or minibuffer window.
 
diff --git a/lisp/pcomplete.el b/lisp/pcomplete.el
index f23b219e1e1..371b61eea1b 100644
--- a/lisp/pcomplete.el
+++ b/lisp/pcomplete.el
@@ -351,65 +351,69 @@ modified to be an empty string, or the desired separation string."
 
 ;;; User Functions:
 
-;;;###autoload
-(defun pcomplete (&optional interactively)
-  "Support extensible programmable completion.
-To use this function, just bind the TAB key to it, or add it to your
-completion functions list (it should occur fairly early in the list)."
-  (interactive "p")
-  (if (and interactively
-           pcomplete-cycle-completions
-           pcomplete-current-completions
-           (memq last-command '(pcomplete
-                                pcomplete-expand-and-complete
-                                pcomplete-reverse)))
-      (progn
-        (delete-backward-char pcomplete-last-completion-length)
-        (if (eq this-command 'pcomplete-reverse)
-            (progn
-              (setq pcomplete-current-completions
-                    (cons (car (last pcomplete-current-completions))
-                          pcomplete-current-completions))
-              (setcdr (last pcomplete-current-completions 2) nil))
-          (nconc pcomplete-current-completions
-                 (list (car pcomplete-current-completions)))
-          (setq pcomplete-current-completions
-                (cdr pcomplete-current-completions)))
-        (pcomplete-insert-entry pcomplete-last-completion-stub
-                                (car pcomplete-current-completions)
-                                nil pcomplete-last-completion-raw))
-    (setq pcomplete-current-completions nil
-          pcomplete-last-completion-raw nil)
-    (catch 'pcompleted
-      (let* ((pcomplete-stub)
-             pcomplete-seen pcomplete-norm-func
-             pcomplete-args pcomplete-last pcomplete-index
-             (pcomplete-autolist pcomplete-autolist)
-             (pcomplete-suffix-list pcomplete-suffix-list)
-             (completions (pcomplete-completions))
-             (result (pcomplete-do-complete pcomplete-stub completions)))
-        (and result
-             (not (eq (car result) 'listed))
-             (cdr result)
-             (pcomplete-insert-entry pcomplete-stub (cdr result)
-                                     (memq (car result)
-                                           '(sole shortest))
-                                     pcomplete-last-completion-raw))))))
+;;; Alternative front-end using the standard completion facilities.
+
+;; The way pcomplete-parse-arguments, pcomplete-stub, and
+;; pcomplete-quote-argument work only works because of some deep
+;; hypothesis about the way the completion work.  Basically, it makes
+;; it pretty much impossible to have completion other than
+;; prefix-completion.
+;;
+;; pcomplete--common-quoted-suffix and pcomplete--table-subvert try to
+;; work around this difficulty with heuristics, but it's
+;; really a hack.
+
+(defvar pcomplete-unquote-argument-function nil)
+
+(defun pcomplete-unquote-argument (s)
+  (cond
+   (pcomplete-unquote-argument-function
+    (funcall pcomplete-unquote-argument-function s))
+   ((null pcomplete-arg-quote-list) s)
+   (t
+    (replace-regexp-in-string "\\\\\\(.\\)" "\\1" s t))))
 
-(defun pcomplete-common-suffix (s1 s2)
+(defun pcomplete--common-suffix (s1 s2)
   (assert (not (or (string-match "\n" s1) (string-match "\n" s2))))
-  (let ((case-fold-search pcomplete-ignore-case))
+  ;; Since S2 is expected to be the "unquoted/expanded" version of S1,
+  ;; there shouldn't be any case difference, even if the completion is
+  ;; case-insensitive.
+  (let ((case-fold-search nil)) ;; pcomplete-ignore-case
     (string-match ".*?\\(.*\\)\n.*\\1\\'" (concat s1 "\n" s2))
     (- (match-end 1) (match-beginning 1))))
 
-(defun pcomplete-table-subvert (table s1 s2 string pred action)
+(defun pcomplete--common-quoted-suffix (s1 s2)
+  "Find the common suffix between S1 and S2 where S1 is the expanded S2.
+S1 is expected to be the unquoted and expanded version of S1.
+Returns (PS1 . PS2), i.e. the shortest prefixes of S1 and S2, such that
+S1 = (concat PS1 SS1) and S2 = (concat PS2 SS2) and
+SS1 = (unquote SS2)."
+  (let* ((cs (pcomplete--common-suffix s1 s2))
+         (ss1 (substring s1 (- (length s1) cs)))
+         (qss1 (pcomplete-quote-argument ss1))
+         qc)
+    (if (and (not (equal ss1 qss1))
+             (setq qc (pcomplete-quote-argument (substring ss1 0 1)))
+             (eq t (compare-strings s2 (- (length s2) cs (length qc) -1)
+                                    (- (length s2) cs -1)
+                                    qc nil nil)))
+        ;; The difference found is just that one char is quoted in S2
+        ;; but not in S1, keep looking before this difference.
+        (pcomplete--common-quoted-suffix
+         (substring s1 0 (- (length s1) cs))
+         (substring s2 0 (- (length s2) cs (length qc) -1)))
+      (cons (substring s1 0 (- (length s1) cs))
+            (substring s2 0 (- (length s2) cs))))))
+
+(defun pcomplete--table-subvert (table s1 s2 string pred action)
   "Completion table that replaces the prefix S1 with S2 in STRING.
 When TABLE, S1 and S2 are provided by `apply-partially', the result
 is a completion table which completes strings of the form (concat S1 S)
 in the same way as TABLE completes strings of the form (concat S2 S)."
   (let* ((str (if (eq t (compare-strings string 0 (length s1) s1 nil nil
                                          completion-ignore-case))
-                  (concat s2 (substring string (length s1)))))
+                  (concat s2 (pcomplete-unquote-argument
+                              (substring string (length s1))))))
          (res (if str (complete-with-action action table str pred))))
     (when res
       (cond
@@ -417,12 +421,14 @@ in the same way as TABLE completes strings of the form (concat S2 S)."
         (let ((beg (or (and (eq (car-safe res) 'boundaries) (cadr res)) 0)))
           (list* 'boundaries
                  (max (length s1)
+                      ;; FIXME: Adjust because of quoting/unquoting.
                       (+ beg (- (length s1) (length s2))))
                  (and (eq (car-safe res) 'boundaries) (cddr res)))))
        ((stringp res)
         (if (eq t (compare-strings res 0 (length s2) s2 nil nil
                                    completion-ignore-case))
-            (concat s1 (substring res (length s2)))))
+            (concat s1 (pcomplete-quote-argument
+                        (substring res (length s2))))))
        ((eq action t)
         (let ((bounds (completion-boundaries str table pred "")))
           (if (>= (car bounds) (length s2))
@@ -435,14 +441,14 @@ in the same way as TABLE completes strings of the form (concat S2 S)."
                                   (substring c (match-end 0))))
                             res))))))))))
         
-
+;; I don't think such commands are usable before first setting up buffer-local
+;; variables to parse args, so there's no point autoloading it.
+;; ;;;###autoload
 (defun pcomplete-std-complete ()
   "Provide standard completion using pcomplete's completion tables.
 Same as `pcomplete' but using the standard completion UI."
   (interactive)
-  ;; FIXME: it fails to unquote/requote the arguments.
   ;; FIXME: it doesn't implement paring.
-  ;; FIXME: when we bring up *Completions* we never bring it back down.
   (catch 'pcompleted
     (let* ((pcomplete-stub)
            pcomplete-seen pcomplete-norm-func
@@ -465,46 +471,98 @@ Same as `pcomplete' but using the standard completion UI."
            ;; pcomplete-stub and works from the buffer's text instead,
            ;; we need to trick minibuffer-complete, into using
            ;; pcomplete-stub without its knowledge.  To that end, we
-           ;; use pcomplete-table-subvert to construct a completion
+           ;; use pcomplete--table-subvert to construct a completion
            ;; table which expects strings using a prefix from the
            ;; buffer's text but internally uses the corresponding
            ;; prefix from pcomplete-stub.
            (beg (max (- (point) (length pcomplete-stub))
-                     ;; Rather than `point-min' we should use the
-                     ;; beginning position of the current arg.
-                     (point-min)))
+                     (pcomplete-begin)))
            (buftext (buffer-substring beg (point)))
-           ;; This isn't always strictly right (e.g. if
-           ;; FOO="toto/$FOO", then completion of /$FOO/bar may
-           ;; result in something incorrect), but given the lack of
-           ;; any other info, it's about as good as it gets, and in
-           ;; practice it should work just fine (fingers crossed).
-           (suflen (pcomplete-common-suffix pcomplete-stub buftext)))
-      (unless (= suflen (length pcomplete-stub))
-        (setq completions
-              (apply-partially
-               'pcomplete-table-subvert
-               completions
-               (substring buftext 0 (- (length buftext) suflen))
-               (substring pcomplete-stub
-                          0 (- (length pcomplete-stub) suflen)))))
+           (table
+            (if (not (equal pcomplete-stub buftext))
+                ;; This isn't always strictly right (e.g. if
+                ;; FOO="toto/$FOO", then completion of /$FOO/bar may
+                ;; result in something incorrect), but given the lack of
+                ;; any other info, it's about as good as it gets, and in
+                ;; practice it should work just fine (fingers crossed).
+                (let ((prefixes (pcomplete--common-quoted-suffix
+                                 pcomplete-stub buftext)))
+                  (apply-partially
+                   'pcomplete--table-subvert
+                   completions
+                   (cdr prefixes) (car prefixes)))
+              (lexical-let ((completions completions))
+                (lambda (string pred action)
+                  (let ((res (complete-with-action
+                              action completions string pred)))
+                    (if (stringp res)
+                        (pcomplete-quote-argument res)
+                      res)))))))
+
       (let ((ol (make-overlay beg (point) nil nil t))
             (minibuffer-completion-table
              ;; Add a space at the end of completion.  Use a terminator-regexp
              ;; that never matches since the terminator cannot appear
              ;; within the completion field anyway.
              (if (zerop (length pcomplete-termination-string))
-                 completions
+                 table
                (apply-partially 'completion-table-with-terminator
                                 (cons pcomplete-termination-string
                                       "\\`a\\`")
-                                completions)))
+                                table)))
             (minibuffer-completion-predicate nil))
         (overlay-put ol 'field 'pcomplete)
         (unwind-protect
             (call-interactively 'minibuffer-complete)
           (delete-overlay ol))))))
 
+;;; Pcomplete's native UI.
+
+;;;###autoload
+(defun pcomplete (&optional interactively)
+  "Support extensible programmable completion.
+To use this function, just bind the TAB key to it, or add it to your
+completion functions list (it should occur fairly early in the list)."
+  (interactive "p")
+  (if (and interactively
+           pcomplete-cycle-completions
+           pcomplete-current-completions
+           (memq last-command '(pcomplete
+                                pcomplete-expand-and-complete
+                                pcomplete-reverse)))
+      (progn
+        (delete-backward-char pcomplete-last-completion-length)
+        (if (eq this-command 'pcomplete-reverse)
+            (progn
+              (setq pcomplete-current-completions
+                    (cons (car (last pcomplete-current-completions))
+                          pcomplete-current-completions))
+              (setcdr (last pcomplete-current-completions 2) nil))
+          (nconc pcomplete-current-completions
+                 (list (car pcomplete-current-completions)))
+          (setq pcomplete-current-completions
+                (cdr pcomplete-current-completions)))
+        (pcomplete-insert-entry pcomplete-last-completion-stub
+                                (car pcomplete-current-completions)
+                                nil pcomplete-last-completion-raw))
+    (setq pcomplete-current-completions nil
+          pcomplete-last-completion-raw nil)
+    (catch 'pcompleted
+      (let* ((pcomplete-stub)
+             pcomplete-seen pcomplete-norm-func
+             pcomplete-args pcomplete-last pcomplete-index
+             (pcomplete-autolist pcomplete-autolist)
+             (pcomplete-suffix-list pcomplete-suffix-list)
+             (completions (pcomplete-completions))
+             (result (pcomplete-do-complete pcomplete-stub completions)))
+        (and result
+             (not (eq (car result) 'listed))
+             (cdr result)
+             (pcomplete-insert-entry pcomplete-stub (cdr result)
+                                     (memq (car result)
+                                           '(sole shortest))
+                                     pcomplete-last-completion-raw))))))
+
 ;;;###autoload
 (defun pcomplete-reverse ()
   "If cycling completion is in use, cycle backwards."
@@ -713,6 +771,7 @@ this is `comint-dynamic-complete-functions'."
 ;;;###autoload
 (defun pcomplete-shell-setup ()
   "Setup `shell-mode' to use pcomplete."
+  ;; FIXME: insufficient
   (pcomplete-comint-setup 'comint-dynamic-complete-functions))
 
 (declare-function comint-bol "comint" (&optional arg))
@@ -789,23 +848,17 @@ this is `comint-dynamic-complete-functions'."
 Magic characters are those in `pcomplete-arg-quote-list'."
   (if (null pcomplete-arg-quote-list)
       filename
-    (let ((len (length filename))
-          (index 0)
-          (result "")
-          replacement char)
-      (while (< index len)
-        (setq replacement (run-hook-with-args-until-success
-                           'pcomplete-quote-arg-hook filename index))
-        (cond
-         (replacement
-          (setq result (concat result replacement)))
-         ((memq (setq char (aref filename index))
-                pcomplete-arg-quote-list)
-          (setq result (concat result (string "\\" char))))
-         (t
-          (setq result (concat result (char-to-string char)))))
-        (setq index (1+ index)))
-      result)))
+    (let ((index 0))
+      (mapconcat (lambda (c)
+                   (prog1
+                       (or (run-hook-with-args-until-success
+                            'pcomplete-quote-arg-hook filename index)
+                           (when (memq c pcomplete-arg-quote-list)
+                             (string "\\" c))
+                           (char-to-string c))
+                     (setq index (1+ index))))
+                 filename
+                 ""))))
 
 ;; file-system completion lists
 
@@ -829,65 +882,46 @@ If PREDICATE is non-nil, it will also be used to refine the match
 \(files for which the PREDICATE returns nil will be excluded).
 If no directory information can be extracted from the completed
 component, `default-directory' is used as the basis for completion."
-  (let* ((name (substitute-env-vars pcomplete-stub))
-         (completion-ignore-case pcomplete-ignore-case)
-         (default-directory (expand-file-name
-                             (or (file-name-directory name)
-                                 default-directory)))
-         above-cutoff)
-    (setq name (file-name-nondirectory name)
-          pcomplete-stub name)
-    (let ((completions
-           (file-name-all-completions name default-directory)))
-      (if regexp
-          (setq completions
-                (pcomplete-pare-list
-                 completions nil
-                 (function
-                  (lambda (file)
-                    (not (string-match regexp file)))))))
-      (if predicate
-          (setq completions
-                (pcomplete-pare-list
-                 completions nil
-                 (function
-                  (lambda (file)
-                    (not (funcall predicate file)))))))
-      (if (or pcomplete-file-ignore pcomplete-dir-ignore)
-          (setq completions
-                (pcomplete-pare-list
-                 completions nil
-                 (function
-                  (lambda (file)
-                    (if (eq (aref file (1- (length file)))
-                            ?/)
-                        (and pcomplete-dir-ignore
-                             (string-match pcomplete-dir-ignore file))
-                      (and pcomplete-file-ignore
-                           (string-match pcomplete-file-ignore file))))))))
-      (setq above-cutoff (and pcomplete-cycle-cutoff-length
-                             (> (length completions)
-                                pcomplete-cycle-cutoff-length)))
-      (sort completions
-            (function
-             (lambda (l r)
-               ;; for the purposes of comparison, remove the
-               ;; trailing slash from directory names.
-               ;; Otherwise, "foo.old/" will come before "foo/",
-               ;; since . is earlier in the ASCII alphabet than
-               ;; /
-               (let ((left (if (eq (aref l (1- (length l)))
-                                   ?/)
-                               (substring l 0 (1- (length l)))
-                             l))
-                     (right (if (eq (aref r (1- (length r)))
-                                    ?/)
-                                (substring r 0 (1- (length r)))
-                              r)))
-                 (if above-cutoff
-                     (string-lessp left right)
-                   (funcall pcomplete-compare-entry-function
-                            left right)))))))))
+  ;; FIXME: obey pcomplete-file-ignore and pcomplete-dir-ignore.
+  ;; FIXME: obey pcomplete-compare-entry-function (tho only if there
+  ;; are less than pcomplete-cycle-cutoff-length completions).
+  ;; FIXME: expand envvars?  shouldn't this be done globally instead?
+  (let* ((reg-pred (when regexp
+                     (lexical-let ((re regexp))
+                       (lambda (f)
+                         ;; (let ((name (file-name-nondirectory f)))
+                         ;;   (if (zerop (length name))
+                         ;;       (setq name (file-name-as-directory
+                         ;;                   (file-name-nondirectory
+                         ;;                    (directory-file-name f)))))
+                         ;;   (string-match re name))
+                         (string-match re f)))))
+         (pred (cond
+                ((null predicate) reg-pred)
+                ((null reg-pred) predicate)
+                (t (lexical-let ((predicate predicate)
+                                 (reg-pred reg-pred))
+                     (lambda (f)
+                       (and (funcall predicate f)
+                            (funcall reg-pred f)))))))
+         (fun
+          (lexical-let ((pred pred)
+                        (dir default-directory))
+            (lambda (s p a)
+              ;; Remember the default-directory that was active when we built
+              ;; the completion table.
+              (let ((default-directory dir)
+                    ;; The old code used only file-name-all-completions
+                    ;; which ignores completion-ignored-extensions.
+                    (completion-ignored-extensions nil))
+                (completion-table-with-predicate
+                 'completion-file-name-table pred 'strict s p a)))))
+         ;; Indirect through a symbol rather than returning a lambda
+         ;; expression, so as to help catch bugs where the caller
+         ;; might treat the lambda expression as a list of completions.
+         (sym (make-symbol "pcomplete-read-file-name-internal")))
+    (fset sym fun)
+    sym))
 
 (defsubst pcomplete-all-entries (&optional regexp predicate)
   "Like `pcomplete-entries', but doesn't ignore any entries."