- "Determine the current directory by scanning the process output for a prompt.
-The prompt to look for is the first item in `dirtrack-list'.
-
-You can toggle directory tracking by using the function `dirtrack-mode'.
-
-If directory tracking does not seem to be working, you can use the
-function `dirtrack-debug-mode' to turn on debugging output."
- (unless (or (null dirtrack-mode)
- (eq (point) (point-min))) ; no output?
- (let (prompt-path
- (current-dir default-directory)
- (dirtrack-regexp (nth 0 dirtrack-list))
- (match-num (nth 1 dirtrack-list)))
- ;; Currently unimplemented, it seems. --Stef
- ;; (multi-line (nth 2 dirtrack-list)))
- (save-excursion
- ;; No match
- (if (not (string-match dirtrack-regexp input))
- (dirtrack-debug-message
- (format "Input `%s' failed to match `dirtrack-list'" input))
- (setq prompt-path (match-string match-num input))
- ;; Empty string
- (if (not (> (length prompt-path) 0))
- (dirtrack-debug-message "Match is empty string")
- ;; Transform prompts into canonical forms
- (setq prompt-path (funcall dirtrack-directory-function
- prompt-path)
- current-dir (funcall dirtrack-canonicalize-function
- current-dir))
- (dirtrack-debug-message
- (format "Prompt is %s\nCurrent directory is %s"
- prompt-path current-dir))
- ;; Compare them
- (if (or (string= current-dir prompt-path)
- (string= current-dir (abbreviate-file-name prompt-path)))
- (dirtrack-debug-message (format "Not changing directory"))
- ;; It's possible that Emacs will think the directory
- ;; won't exist (eg, rlogin buffers)
- (if (file-accessible-directory-p prompt-path)
- ;; Change directory
- (and (shell-process-cd prompt-path)
- (run-hooks 'dirtrack-directory-change-hook)
- (dirtrack-debug-message
- (format "Changing directory to %s" prompt-path)))
- (warn "Directory %s does not exist" prompt-path)))
- )))))
+ "Determine the current directory from the process output for a prompt.
+This filter function is used by `dirtrack-mode'. It looks for
+the prompt specified by `dirtrack-list', and calls
+`shell-process-cd' if the directory seems to have changed away
+from `default-directory'."
+ (when (and dirtrack-mode
+ (not (eq (point) (point-min)))) ; there must be output
+ (save-excursion ; What's this for? -- cyd
+ (if (not (string-match (nth 0 dirtrack-list) input))
+ ;; No match
+ (dirtrack-debug-message
+ "Input failed to match `dirtrack-list': " input)
+ (let ((prompt-path (match-string (nth 1 dirtrack-list) input))
+ temp)
+ (cond
+ ;; Don't do anything for empty string
+ ((string-equal prompt-path "")
+ (dirtrack-debug-message "Prompt match gives empty string: " input))
+ ;; If the prompt contains an absolute file name, call
+ ;; `shell-process-cd' if the directory has changed.
+ ((file-name-absolute-p prompt-path)
+ ;; Transform prompts into canonical forms
+ (let ((orig-prompt-path (funcall dirtrack-directory-function
+ prompt-path))
+ (current-dir (funcall dirtrack-canonicalize-function
+ default-directory)))
+ (setq prompt-path (shell-prefixed-directory-name orig-prompt-path))
+ ;; Compare them
+ (if (or (string-equal current-dir prompt-path)
+ (string-equal (expand-file-name current-dir)
+ (expand-file-name prompt-path)))
+ (dirtrack-debug-message "Not changing directory: " current-dir)
+ ;; It's possible that Emacs thinks the directory
+ ;; doesn't exist (e.g. rlogin buffers)
+ (if (file-accessible-directory-p prompt-path)
+ ;; `shell-process-cd' adds the prefix, so we need
+ ;; to give it the original (un-prefixed) path.
+ (progn
+ (shell-process-cd orig-prompt-path)
+ (run-hooks 'dirtrack-directory-change-hook)
+ (dirtrack-debug-message "Changing directory to "
+ prompt-path))
+ (dirtrack-debug-message "Not changing to non-existent directory: "
+ prompt-path)))))
+ ;; If the file name is non-absolute, try and see if it
+ ;; seems to be up or down from where we were.
+ ((string-match "\\`\\(.*\\)\\(?:/.*\\)?\n\\(.*/\\)\\1\\(?:/.*\\)?\\'"
+ (setq temp
+ (concat prompt-path "\n" default-directory)))
+ (shell-process-cd (concat (match-string 2 temp)
+ prompt-path))
+ (run-hooks 'dirtrack-directory-change-hook)))))))