diff options
Diffstat (limited to 'lisp/emacs-lisp/backtrace.el')
| -rw-r--r-- | lisp/emacs-lisp/backtrace.el | 52 |
1 files changed, 48 insertions, 4 deletions
diff --git a/lisp/emacs-lisp/backtrace.el b/lisp/emacs-lisp/backtrace.el index b6ca2890764..5169c305035 100644 --- a/lisp/emacs-lisp/backtrace.el +++ b/lisp/emacs-lisp/backtrace.el @@ -66,7 +66,14 @@ abbreviate the forms it prints." (cl-defstruct (backtrace-frame (:constructor backtrace-make-frame)) - evald fun args flags locals buffer pos) + evald ; Non-nil if argument evaluation is complete. + fun ; The function called/to call in this frame. + args ; Either evaluated or unevaluated arguments to the function. + flags ; A plist, possible properties are :debug-on-exit and :source-available. + locals ; An alist containing variable names and values. + buffer ; If non-nil, the buffer in use by eval-buffer or eval-region. + pos ; The position in the buffer. + ) (cl-defun backtrace-get-frames (&optional base &key (constructor #'backtrace-make-frame)) @@ -181,6 +188,15 @@ This is commonly used to recompute `backtrace-frames'.") (defvar-local backtrace-print-function #'cl-prin1 "Function used to print values in the current Backtrace buffer.") +(defvar-local backtrace-goto-source-functions nil + "Abnormal hook used to jump to the source code for the current frame. +Each hook function is called with no argument, and should return +non-nil if it is able to switch to the buffer containing the +source code. Execution of the hook will stop if one of the +functions returns non-nil. When adding a function to this hook, +you should also set the :source-available flag for the backtrace +frames where the source code location is known.") + (defvar backtrace-mode-map (let ((map (copy-keymap special-mode-map))) (set-keymap-parent map button-buffer-map) @@ -188,6 +204,7 @@ This is commonly used to recompute `backtrace-frames'.") (define-key map "p" 'backtrace-backward-frame) (define-key map "v" 'backtrace-toggle-locals) (define-key map "#" 'backtrace-toggle-print-circle) + (define-key map "s" 'backtrace-goto-source) (define-key map "\C-m" 'backtrace-help-follow-symbol) (define-key map "+" 'backtrace-pretty-print) (define-key map "-" 'backtrace-collapse) @@ -212,6 +229,12 @@ This is commonly used to recompute `backtrace-frames'.") :help "Use line breaks and indentation to make a form more readable"] ["Collapse to Single Line" backtrace-collapse] "--" + ["Go to Source" backtrace-goto-source + :active (and (backtrace-get-index) + (plist-get (backtrace-frame-flags + (nth (backtrace-get-index) backtrace-frames)) + :source-available)) + :help "Show the source code for the current frame"] ["Help for Symbol" backtrace-help-follow-symbol :help "Show help for symbol at point"] ["Describe Backtrace Mode" describe-mode @@ -219,6 +242,9 @@ This is commonly used to recompute `backtrace-frames'.") map) "Local keymap for `backtrace-mode' buffers.") +(defconst backtrace--flags-width 2 + "Width in characters of the flags for a backtrace frame.") + ;;; Navigation and Text Properties ;; This mode uses the following text properties: @@ -580,6 +606,20 @@ content of the sexp." '(backtrace-section backtrace-index backtrace-view backtrace-form)))) +(defun backtrace-goto-source () + "If its location is known, jump to the source code for the frame at point." + (interactive) + (let* ((index (or (backtrace-get-index) (user-error "Not in a stack frame"))) + (frame (nth index backtrace-frames)) + (source-available (plist-get (backtrace-frame-flags frame) + :source-available))) + (unless (and source-available + (catch 'done + (dolist (func backtrace-goto-source-functions) + (when (funcall func) + (throw 'done t))))) + (user-error "Source code location not known")))) + (defun backtrace-help-follow-symbol (&optional pos) "Follow cross-reference at POS, defaulting to point. For the cross-reference format, see `help-make-xrefs'." @@ -681,8 +721,12 @@ property for use by navigation." (defun backtrace--print-flags (frame view) "Print the flags of a backtrace FRAME if enabled in VIEW." (let ((beg (point)) - (flag (plist-get (backtrace-frame-flags frame) :debug-on-exit))) - (insert (if (and (plist-get view :show-flags) flag) "* " " ")) + (flag (plist-get (backtrace-frame-flags frame) :debug-on-exit)) + (source (plist-get (backtrace-frame-flags frame) :source-available))) + (when (plist-get view :show-flags) + (when source (insert ">")) + (when flag (insert "*"))) + (insert (make-string (- backtrace--flags-width (- (point) beg)) ?\s)) (put-text-property beg (point) 'backtrace-section 'func))) (defun backtrace--print-func-and-args (frame _view) @@ -770,7 +814,7 @@ Fall back to `prin1' if there is an error." (let ((props (backtrace-get-text-properties begin)) (inhibit-read-only t) (standard-output (current-buffer))) - (delete-char 2) + (delete-char backtrace--flags-width) (backtrace--print-flags (nth (backtrace-get-index) backtrace-frames) view) (add-text-properties begin (point) props)))))) |