blob: 070fada13a9e22d38cdad4e405470e79c1b15fe6 [file] [log] [blame]
;; Copyright (c) 2011 The Chromium Authors. All rights reserved.
;; Use of this source code is governed by a BSD-style license that can be
;; found in the LICENSE file.
;; Set up flymake for use with chromium code. Uses ninja (since none of the
;; other chromium build systems have latency that allows interactive use).
;;
;; Requires a modern emacs (GNU Emacs >= 23) and that gyp has already generated
;; the build.ninja file(s). See defcustoms below for settable knobs.
(require 'flymake)
(defcustom cr-flymake-ninja-build-file "out/Debug/build.ninja"
"Relative path from chromium's src/ directory to the
build.ninja file to use.")
(defcustom cr-flymake-ninja-executable "ninja"
"Ninja executable location; either in $PATH or explicitly given.")
(defun cr-flymake-chromium-src ()
"Return chromium's src/ directory, or nil on failure."
(locate-dominating-file buffer-file-truename cr-flymake-ninja-build-file))
(defun cr-flymake-string-prefix-p (prefix str)
"Return non-nil if PREFIX is a prefix of STR (23.2 has string-prefix-p but
that's case insensitive and also 23.1 doesn't have it)."
(string= prefix (substring str 0 (length prefix))))
(defun cr-flymake-current-file-name ()
"Return the relative path from chromium's src/ directory to the
file backing the current buffer or nil if it doesn't look like
we're under chromium/src/."
(when (and (cr-flymake-chromium-src)
(cr-flymake-string-prefix-p
(cr-flymake-chromium-src) buffer-file-truename))
(substring buffer-file-truename (length (cr-flymake-chromium-src)))))
(defun cr-flymake-from-build-to-src-root ()
"Return a path fragment for getting from the build.ninja file to src/."
(replace-regexp-in-string
"[^/]+" ".."
(substring
(file-name-directory
(file-truename (or (and (cr-flymake-string-prefix-p
"/" cr-flymake-ninja-build-file)
cr-flymake-ninja-build-file)
(concat (cr-flymake-chromium-src)
cr-flymake-ninja-build-file))))
(length (cr-flymake-chromium-src)))))
(defun cr-flymake-getfname (file-name-from-error-message)
"Strip cruft from the passed-in filename to help flymake find the real file."
(file-name-nondirectory file-name-from-error-message))
(defun cr-flymake-ninja-command-line ()
"Return the command-line for running ninja, as a list of strings, or nil if
we're not during a save"
(unless (buffer-modified-p)
(list cr-flymake-ninja-executable
(list "-C"
(concat (cr-flymake-chromium-src)
(file-name-directory cr-flymake-ninja-build-file))
(concat (cr-flymake-from-build-to-src-root)
(cr-flymake-current-file-name) "^")))))
(defun cr-flymake-kick-off-check-after-save ()
"Kick off a syntax check after file save, if flymake-mode is on."
(when flymake-mode (flymake-start-syntax-check)))
(defadvice next-error (around cr-flymake-next-error activate)
"If flymake has something to say, let it say it; otherwise
revert to normal next-error behavior."
(if (not flymake-err-info)
(condition-case msg
ad-do-it
(error (message "%s" (prin1-to-string msg))))
(flymake-goto-next-error)
;; copy/pasted from flymake-display-err-menu-for-current-line because I
;; couldn't find a way to have it tell me what the relevant error for this
;; line was in a single call:
(let* ((line-no (flymake-current-line-no))
(line-err-info-list
(nth 0 (flymake-find-err-info flymake-err-info line-no)))
(menu-data (flymake-make-err-menu-data line-no line-err-info-list)))
(prin1 (car (car (car (cdr menu-data)))) t))))
(defun cr-flymake-find-file ()
"Enable flymake, but only if it makes sense, and immediately
disable timer-based execution."
(when (and (not flymake-mode)
(not buffer-read-only)
(cr-flymake-current-file-name))
;; Since flymake-allowed-file-name-masks requires static regexps to match
;; against, can't use cr-flymake-chromium-src here. Instead we add a
;; generic regexp, but only to a buffer-local version of the variable.
(set (make-local-variable 'flymake-allowed-file-name-masks)
(list (list "\\.c\\(\\|c\\|pp\\)"
'cr-flymake-ninja-command-line
'ignore
'cr-flymake-getfname)))
(flymake-find-file-hook)
(if flymake-mode
(cancel-timer flymake-timer)
(kill-local-variable 'flymake-allowed-file-name-masks))))
(add-hook 'find-file-hook 'cr-flymake-find-file 'append)
(add-hook 'after-save-hook 'cr-flymake-kick-off-check-after-save)
;; Show flymake infrastructure ERRORs in hopes of fixing them. Set to 3 for
;; DEBUG-level output from flymake.el.
(setq flymake-log-level 0)
(provide 'flymake-chromium)