Enhancements to pdbtrack.

pdbtrack now handles correctly the case where the stacktrace
information is on the second line.

All python buffers not opened by the user and used for tracking are
closed automatically when tracking process finishes.

Simplified code for keeping the tracked buffer.

Removed vars:
 + python-pdbtrack-tracking-buffers

Removed functions:
 + python-pdbtrack-get-or-add-tracking-buffers

New vars:
 + python-pdbtrack-tracked-buffer
 + python-pdbtrack-buffers-to-kill

New functions:
 + python-pdbtrack-set-tracked-buffer

1 files changed, 42 insertions, 40 deletions

diff --git a/lisp/progmodes/python.el b/lisp/progmodes/python.el
index 89f454ed95b..17afb0ee309 100644
--- a/lisp/progmodes/python.el
+++ b/lisp/progmodes/python.el
@@ -1680,28 +1680,27 @@ Used to extract the current line and module being inspected."
   :group 'python
   :safe 'stringp)
 
-(defvar python-pdbtrack-tracking-buffers nil
-  "Alist containing elements of form (#<buffer> . #<buffer>).
-The car of each element of the alist is the tracking buffer and
-the cdr is the tracked buffer.")
-
-(defun python-pdbtrack-get-or-add-tracking-buffers (file-name)
-  "Get/Add a tracked buffer for the current buffer and FILE-NAME.
-Internally it uses the `python-pdbtrack-tracking-buffers' alist.
-Returns a cons with the form:
- * (#<tracking buffer> . #< tracked buffer>)."
-  (let ((tracking-buffers
-         (cons (current-buffer)
-               (or (get-file-buffer file-name)
-                   (find-file-noselect file-name)))))
-    (set-buffer (cdr tracking-buffers))
-    (when (not (eq major-mode 'python-mode))
-      (python-mode))
-    (set-buffer (car tracking-buffers))
-    (assq-delete-all (current-buffer) python-pdbtrack-tracking-buffers)
-    (setq python-pdbtrack-tracking-buffers
-          (cons tracking-buffers python-pdbtrack-tracking-buffers))
-    tracking-buffers))
+(defvar python-pdbtrack-tracked-buffer nil
+  "Variable containing the value of the current tracked buffer.
+Never set this variable directly, use
+`python-pdbtrack-set-tracked-buffer' instead.")
+(make-variable-buffer-local 'python-pdbtrack-tracked-buffer)
+
+(defvar python-pdbtrack-buffers-to-kill nil
+  "List of buffers to be deleted after tracking finishes.")
+(make-variable-buffer-local 'python-pdbtrack-buffers-to-kill)
+
+(defun python-pdbtrack-set-tracked-buffer (file-name)
+  "Set the buffer for FILE-NAME as the tracked buffer.
+Internally it uses the `python-pdbtrack-tracked-buffer' variable.
+Returns the tracked buffer."
+  (let ((file-buffer (get-file-buffer file-name)))
+    (if file-buffer
+        (setq python-pdbtrack-tracked-buffer file-buffer)
+      (setq file-buffer (find-file-noselect file-name))
+      (when (not (member file-buffer python-pdbtrack-buffers-to-kill))
+        (add-to-list 'python-pdbtrack-buffers-to-kill file-buffer)))
+    file-buffer))
 
 (defun python-pdbtrack-comint-output-filter-function (output)
   "Move overlay arrow to current pdb line in tracked buffer.
@@ -1712,21 +1711,24 @@ Argument OUTPUT is a string with the output from the comint process."
            (line-number)
            (file-name
             (with-temp-buffer
-              ;; OK, this sucks but for some reason
-              ;; string-match was not doing his trick.
               (insert full-output)
               (goto-char (point-min))
-              (when (looking-at python-pdbtrack-stacktrace-info-regexp)
+              ;; OK, this sucked but now it became a cool hack. The
+              ;; stacktrace information normally is on the first line
+              ;; but in some cases (like when doing a step-in) it is
+              ;; on the second.
+              (when (or (looking-at python-pdbtrack-stacktrace-info-regexp)
+                        (and (forward-line)
+                             (looking-at python-pdbtrack-stacktrace-info-regexp)))
                 (setq line-number (string-to-number
                                    (match-string-no-properties 2)))
                 (match-string-no-properties 1)))))
       (if (and file-name line-number)
-          (let* ((tracking-buffers
-                  (python-pdbtrack-get-or-add-tracking-buffers file-name))
-                 (tracked-buffer-window
-                  (get-buffer-window (cdr tracking-buffers)))
+          (let* ((tracked-buffer (python-pdbtrack-set-tracked-buffer file-name))
+                 (shell-buffer (current-buffer))
+                 (tracked-buffer-window (get-buffer-window tracked-buffer))
                  (tracked-buffer-line-pos))
-            (with-current-buffer (cdr tracking-buffers)
+            (with-current-buffer tracked-buffer
               (set (make-local-variable 'overlay-arrow-string) "=>")
               (set (make-local-variable 'overlay-arrow-position) (make-marker))
               (setq tracked-buffer-line-pos (progn
@@ -1737,16 +1739,16 @@ Argument OUTPUT is a string with the output from the comint process."
                 (set-window-point
                  tracked-buffer-window tracked-buffer-line-pos))
               (set-marker overlay-arrow-position tracked-buffer-line-pos))
-            (pop-to-buffer (cdr tracking-buffers))
-            (switch-to-buffer-other-window (car tracking-buffers)))
-        (let ((tracking-buffers (assq (current-buffer)
-                                      python-pdbtrack-tracking-buffers)))
-          (when tracking-buffers
-            (with-current-buffer (cdr tracking-buffers)
-              (set-marker overlay-arrow-position nil))
-            (setq python-pdbtrack-tracking-buffers
-                  (assq-delete-all (current-buffer)
-                                   python-pdbtrack-tracking-buffers)))))))
+            (pop-to-buffer tracked-buffer)
+            (switch-to-buffer-other-window shell-buffer))
+        (when python-pdbtrack-tracked-buffer
+          (with-current-buffer python-pdbtrack-tracked-buffer
+            (set-marker overlay-arrow-position nil))
+          (mapc #'(lambda (buffer)
+                    (ignore-errors (kill-buffer buffer)))
+                python-pdbtrack-buffers-to-kill)
+          (setq python-pdbtrack-tracked-buffer nil
+                python-pdbtrack-buffers-to-kill nil)))))
   output)