; Wait until post-command, or bad auto-fill call to print stacktrace

If we popup a warning as soon as yas--original-auto-fill-function is
changed to nil, we'll have false positives in cases where
auto-fill-function was *also* going to be turned nil afterwards.

* yasnippet.el (yas--watch-auto-fill-backtrace): New variable, to save
backtrace into.
(yas--watch-auto-fill): Check both yas--original-auto-fill-function
and auto-fill-function, but only save the backtrace, don't popup the
debugger.
(yas--auto-fill): Also print the saved backtrace if
yas--original-auto-fill-function is nil.
(yas--post-command-handler): Print the saved backtrace if
yas--original-auto-fill-function and auto-fill-function is
yas--auto-fill, which means we're in a bad state.
This commit is contained in:
Noam Postavsky 2018-03-19 08:54:13 -04:00
parent a0d2cff79b
commit fa6a71c42d

View File

@ -582,8 +582,16 @@ override bindings from other packages (e.g., `company-mode')."
"The original value of `auto-fill-function'.")
(make-variable-buffer-local 'yas--original-auto-fill-function)
(defun yas--watch-auto-fill (_sym newval op _where)
(when (and (null newval) (eq auto-fill-function 'yas--auto-fill)
(defvar yas--watch-auto-fill-backtrace nil)
(defun yas--watch-auto-fill (sym newval op _where)
(when (and (or (and (eq sym 'yas--original-auto-fill-function)
(null newval)
(eq auto-fill-function 'yas--auto-fill))
(and (eq sym 'auto-fill-function)
(eq newval 'yas--auto-fill)
(null yas--original-auto-fill-function)))
(null yas--watch-auto-fill-backtrace)
(fboundp 'backtrace-frames) ; Suppress compiler warning.
;; If we're about to change `auto-fill-function' too,
;; it's okay (probably).
@ -592,11 +600,14 @@ override bindings from other packages (e.g., `company-mode')."
(cl-member 'kill-all-local-variables
(backtrace-frames 'yas--watch-auto-fill)
:key (lambda (frame) (nth 1 frame))))))
(debug nil "`yas--original-auto-fill-function' unexpectedly nil! Please report this backtrace (hit `c' to continue)")) )
(setq yas--watch-auto-fill-backtrace
(backtrace-frames 'yas--watch-auto-fill))))
;; Try to get more info on #873/919 (this only works for Emacs 26+).
(when (fboundp 'add-variable-watcher)
(add-variable-watcher 'yas--original-auto-fill-function
#'yas--watch-auto-fill)
(add-variable-watcher 'auto-fill-function
#'yas--watch-auto-fill))
(defun yas--snippet-next-id ()
@ -3724,8 +3735,14 @@ field start. This hook does nothing if an undo is in progress."
(lwarn '(yasnippet auto-fill bug) :error
"`yas--original-auto-fill-function' unexpectedly nil in %S! Disabling auto-fill.
%S
`auto-fill-function': %S"
(current-buffer) yas--fill-fun-values fill-fun-values)
`auto-fill-function': %S\n%s"
(current-buffer) yas--fill-fun-values fill-fun-values
(if (fboundp 'backtrace--print-frame)
(with-output-to-string
(mapc (lambda (frame)
(apply #'backtrace--print-frame frame))
yas--watch-auto-fill-backtrace))
""))
;; Try to avoid repeated triggering of this bug.
(auto-fill-mode -1)
;; Don't pop up more than once in a session (still log though).
@ -4718,6 +4735,18 @@ When multiple expressions are found, only the last one counts."
;;
(defun yas--post-command-handler ()
"Handles various yasnippet conditions after each command."
(when (and yas--watch-auto-fill-backtrace
(fboundp 'backtrace--print-frame)
(null yas--original-auto-fill-function)
(eq auto-fill-function 'yas--auto-fill))
(lwarn '(yasnippet auto-fill bug) :error
"`yas--original-auto-fill-function' unexpectedly nil! Please report this backtrace\n%S"
(with-output-to-string
(mapc #'backtrace--print-frame
yas--watch-auto-fill-backtrace)))
;; Don't pop up more than once in a session (still log though).
(defvar warning-suppress-types) ; `warnings' is autoloaded by `lwarn'.
(add-to-list 'warning-suppress-types '(yasnippet auto-fill bug)))
(condition-case err
(progn (yas--finish-moving-snippets)
(cond ((eq 'undo this-command)