Extend flymake's warning predicate to be a function. Test suite for flymake.

* lisp/progmodes/flymake.el (flymake-warning-predicate): New.
(flymake-parse-line): Use it.
(flymake-warning-re): Make obsolete alias to
`flymake-warning-predicate'.
* doc/misc/flymake.texi (Parsing the output, Customizable variables):
Add reference to `flymake-warning-predicate'.
* test/automated/flymake-tests.el:
* test/automated/flymake/warnpred/Makefile
* test/automated/flymake/warnpred/test.c
* test/automated/flymake/warnpred/test.pl: New files.

Fixes: debbugs:14217

9 files changed, 196 insertions, 65 deletions

diff --git a/doc/misc/ChangeLog b/doc/misc/ChangeLog
index 2368c351ab..e167c73f7f 100644
--- a/doc/misc/ChangeLog
+++ b/doc/misc/ChangeLog
@@ -1,3 +1,8 @@
+2013-06-21  Eduard Wiebe  <usenet@pusto.de>
+
+	* flymake.texi (Parsing the output, Customizable variables):
+	Add reference to `flymake-warning-predicate'.
+
 2013-06-19  Michael Albinus  <michael.albinus@gmx.de>
 
 	* tramp.texi (Top, Configuration): Insert section `Predefined
@@ -101,8 +106,8 @@
 
 2013-03-08  Jay Belanger  <jay.p.belanger@gmail.com>
 
-	* calc.texi (Basic Operations on Units): Fix
-	cross-reference.
+	* calc.texi (Basic Operations on Units):
+	Fix cross-reference.
 
 2013-03-07  Katsumi Yamaoka  <yamaoka@jpl.org>
 
@@ -140,8 +145,8 @@
 
 	* tramp.texi (Inline methods): Remove "ssh1", "ssh2", "plink1"
 	and "plink2" entries.  "plink2" is obsolete for a long time.
-	(External methods): Remove "scp1" and "scp2" entries.  Explain
-	user name and host name specification for "adb".
+	(External methods): Remove "scp1" and "scp2" entries.
+	Explain user name and host name specification for "adb".
 
 2013-02-28  Michael Albinus  <michael.albinus@gmx.de>
 
@@ -221,8 +226,8 @@
 	from ede new.
 	(Simple projects): Re-write to not talk about ede-simple-project
 	which is deprecated, and instead use the term to mean projects
-	that don't do much management, just project wrapping.  Add
-	ede-generic-project link.
+	that don't do much management, just project wrapping.
+	Add ede-generic-project link.
 	(ede-generic-project): New node (bug#11441).
 
 2013-02-07  Glenn Morris  <rgm@gnu.org>
@@ -361,8 +366,8 @@
 
 2012-12-24  Lars Ingebrigtsen  <larsi@gnus.org>
 
-	* gnus.texi (Browse Foreign Server): Document
-	`gnus-browse-delete-group'.
+	* gnus.texi (Browse Foreign Server):
+	Document `gnus-browse-delete-group'.
 
 2012-12-22  Glenn Morris  <rgm@gnu.org>
 
@@ -599,8 +604,8 @@
 	Improve docs for url-queue-*.
 	(Supported URL Types): Copyedits.  Delete empty subnodes.
 
-	* url.texi (Introduction): Rename from Getting Started.  Rewrite
-	the introduction.
+	* url.texi (Introduction): Rename from Getting Started.
+	Rewrite the introduction.
 	(URI Parsing): Rewrite.  Omit the obsolete attributes slot.
 
 2012-11-10  Glenn Morris  <rgm@gnu.org>
@@ -700,14 +705,14 @@
 
 2012-10-26  Bastien Guerry  <bzg@gnu.org>
 
-	* org.texi (Installation): Update the link to Org's ELPA.  Also
-	don't mention org-install.el anymore as the replacement file
+	* org.texi (Installation): Update the link to Org's ELPA.
+	Also don't mention org-install.el anymore as the replacement file
 	org-loaddefs.el is now loaded by org.el.
 
 2012-10-25  Michael Albinus  <michael.albinus@gmx.de>
 
-	* tramp.texi (Frequently Asked Questions): Mention
-	`tramp-completion-reread-directory-timeout' for performance
+	* tramp.texi (Frequently Asked Questions):
+	Mention `tramp-completion-reread-directory-timeout' for performance
 	improvement.
 
 2012-10-25  Glenn Morris  <rgm@gnu.org>
@@ -830,8 +835,8 @@
 	(Referencing Labels): Update regarding reference styles.
 	(Citation Styles): Mention support for ConTeXt.
 	(Options (Defining Label Environments)): Fix typo.
-	(Options (Creating Citations)): Document
-	`reftex-cite-key-separator'.
+	(Options (Creating Citations)):
+	Document `reftex-cite-key-separator'.
 
 2012-09-30  Achim Gratz  <Stromeko@Stromeko.DE>
 
@@ -863,8 +868,8 @@
 
 2012-09-30  Bastien Guerry  <bzg@gnu.org>
 
-	* org.texi (Installation, Feedback, Batch execution): Use
-	(add-to-list 'load-path ... t) for the contrib dir.
+	* org.texi (Installation, Feedback, Batch execution):
+	Use (add-to-list 'load-path ... t) for the contrib dir.
 
 	* org.texi (results): Update documentation for ":results drawer"
 	and ":results org".
@@ -891,8 +896,8 @@
 	(Agenda commands): Reorder.  Document `*' to toggle persistent
 	marks.
 
-	* org.texi (Agenda dispatcher): Mention
-	`org-toggle-agenda-sticky'.
+	* org.texi (Agenda dispatcher):
+	Mention `org-toggle-agenda-sticky'.
 	(Agenda commands, Exporting Agenda Views): Fix typo.
 
 	* org.texi (Templates in contexts, Setting Options): Update to
@@ -1067,8 +1072,8 @@
 	(Unsafe Simplifications): Mention `m E'.
 	(Simplification of Units): Mention `m U'.
 	(Trigonometric/Hyperbolic Functions, Reducing and Mapping)
-	(Kinds of Declarations, Functions for Declarations): Mention
-	"algebraic simplifications" instead of `a s'.
+	(Kinds of Declarations, Functions for Declarations):
+	Mention "algebraic simplifications" instead of `a s'.
 	(Algebraic Entry): Remove mention of default simplifications.
 
 2012-07-30  Jay Belanger  <jay.p.belanger@gmail.com>
@@ -1100,8 +1105,8 @@
 
 2012-07-06  Michael Albinus  <michael.albinus@gmx.de>
 
-	* tramp.texi (Multi-hops): Introduce
-	`tramp-restricted-shell-hosts-alist'.
+	* tramp.texi (Multi-hops):
+	Introduce `tramp-restricted-shell-hosts-alist'.
 
 2012-06-26  Lars Magne Ingebrigtsen  <larsi@gnus.org>
 
@@ -1293,8 +1298,8 @@
 	(Synchronous Methods): Remove obsolete dbus-call-method-non-blocking.
 	(Asynchronous Methods): Fix description of
 	dbus-call-method-asynchronously.
-	(Receiving Method Calls): Fix some minor errors.  Add
-	dbus-interface-emacs.
+	(Receiving Method Calls): Fix some minor errors.
+	Add dbus-interface-emacs.
 	(Signals): Describe unicast signals and the new match rules.
 	(Alternative Buses): Add the PRIVATE optional argument to
 	dbus-init-bus.  Describe its new return value.  Add dbus-setenv.
@@ -1327,8 +1332,8 @@
 
 2012-04-09  Eli Zaretskii  <eliz@gnu.org>
 
-	* makefile.w32-in (INFO_TARGETS, DVI_TARGETS, clean): Add
-	emacs-gnutls.
+	* makefile.w32-in (INFO_TARGETS, DVI_TARGETS, clean):
+	Add emacs-gnutls.
 	($(infodir)/emacs-gnutls, emacs-gnutls.dvi): New targets.
 
 2012-04-09  Teodor Zlatanov  <tzz@lifelogs.com>
@@ -1431,7 +1436,7 @@
 
 2012-04-01  Eric Schulte  <eric.schulte@gmx.com>
 
-	* org.texi (Key bindings and useful functions): Updated babel key
+	* org.texi (Key bindings and useful functions): Update babel key
 	binding documentation in manual.
 
 2012-04-01  Eric Schulte  <eric.schulte@gmx.com>
@@ -1532,8 +1537,8 @@
 
 2012-02-13  Lars Ingebrigtsen  <larsi@gnus.org>
 
-	* gnus.texi (Customizing the IMAP Connection): Mention
-	nnimap-record-commands.
+	* gnus.texi (Customizing the IMAP Connection):
+	Mention nnimap-record-commands.
 
 2012-02-10  Glenn Morris  <rgm@gnu.org>
 
@@ -1604,8 +1609,8 @@
 
 2012-01-03  Bernt Hansen  <bernt@norang.ca>
 
-	* org.texi (Agenda commands): Document
-	`org-clock-report-include-clocking-task'.
+	* org.texi (Agenda commands):
+	Document `org-clock-report-include-clocking-task'.
 
 2012-01-03  Bastien Guerry  <bzg@gnu.org>
 
@@ -1690,8 +1695,8 @@
 
 2012-01-03  Eric Schulte  <schulte.eric@gmail.com>
 
-	* org.texi (Buffer-wide header arguments): Update
-	documentation to reflect removal of #+PROPERTIES.
+	* org.texi (Buffer-wide header arguments):
+	Update documentation to reflect removal of #+PROPERTIES.
 
 2012-01-03  Carsten Dominik  <carsten.dominik@gmail.com>
 
@@ -1852,7 +1857,7 @@
 
 	* mh-e.texi (VERSION, EDITION, UPDATED, UPDATE-MONTH): Update for
 	release 8.3.
-	(Preface): Updated support information.
+	(Preface): Update support information.
 	(From Bill Wohler): Reset text to original version.  As a
 	historical quote, the tense should be correct in the time that it
 	was written.
@@ -2054,8 +2059,8 @@
 
 2011-08-15  Bastien Guerry  <bzg@gnu.org>
 
-	* org.texi (Dynamic blocks, Structure editing): Mention
-	the function `org-narrow-to-block'.
+	* org.texi (Dynamic blocks, Structure editing):
+	Mention the function `org-narrow-to-block'.
 
 2011-08-15  Eric Schulte  <schulte.eric@gmail.com>
 
@@ -2082,15 +2087,15 @@
 
 2011-08-15  Eric Schulte  <schulte.eric@gmail.com>
 
-	* org.texi (Conflicts): Changed "yasnippets" to "yasnippet" and
+	* org.texi (Conflicts): Change "yasnippets" to "yasnippet" and
 	added extra whitespace around functions to be consistent with the
 	rest of the section.
 
 2011-08-15  Eric Schulte  <schulte.eric@gmail.com>
 
-	* org.texi (Evaluating code blocks): Expanded discussion of
+	* org.texi (Evaluating code blocks): Expand discussion of
 	#+call: line syntax.
-	(Header arguments in function calls): Expanded discussion of
+	(Header arguments in function calls): Expand discussion of
 	#+call: line syntax.
 
 2011-08-15  Eric Schulte  <schulte.eric@gmail.com>
@@ -2120,12 +2125,12 @@
 
 2011-08-15  Tom Dye  <tsd@tsdye.com>
 
-	* org.texi (cache): Improved documentation of code block caches.
+	* org.texi (cache): Improve documentation of code block caches.
 
 2011-08-15  Tom Dye  <tsd@tsdye.com>
 
-	* org.texi (Code block specific header arguments): Documentation
-	of multi-line header arguments.
+	* org.texi (Code block specific header arguments):
+	Documentation of multi-line header arguments.
 
 2011-08-15  Eric Schulte  <schulte.eric@gmail.com>
 
@@ -2181,15 +2186,15 @@
 
 2011-07-04  Michael Albinus  <michael.albinus@gmx.de>
 
-	* tramp.texi (Cleanup remote connections): Add
-	`tramp-cleanup-this-connection'.
+	* tramp.texi (Cleanup remote connections):
+	Add `tramp-cleanup-this-connection'.
 
 2011-07-03  Lars Magne Ingebrigtsen  <larsi@gnus.org>
 
 	* gnus.texi (Subscription Methods): Link to "Group Levels" to explain
 	zombies.
 	(Checking New Groups): Ditto (bug#8974).
-	(Checking New Groups): Moved the reference to the right place.
+	(Checking New Groups): Move the reference to the right place.
 
 2011-07-03  Dave Abrahams  <dave@boostpro.com>  (tiny change)
 
@@ -2216,8 +2221,8 @@
 
 2011-06-26  Lars Magne Ingebrigtsen  <larsi@gnus.org>
 
-	* gnus.texi (Summary Mail Commands): Document
-	`gnus-summary-reply-to-list-with-original'.
+	* gnus.texi (Summary Mail Commands):
+	Document `gnus-summary-reply-to-list-with-original'.
 
 2011-06-20  Stefan Monnier  <monnier@iro.umontreal.ca>
 
@@ -2280,7 +2285,7 @@
 
 	* gnus.texi (nnmairix caveats, Setup, Registry Article Refer Method)
 	(Fancy splitting to parent, Store arbitrary data):
-	Updated gnus-registry docs.
+	Update gnus-registry docs.
 
 2011-04-13  Juanma Barranquero  <lekktu@gmail.com>
 
@@ -3401,8 +3406,8 @@
 
 	Sync with Tramp 2.1.19.
 
-	* tramp.texi (Inline methods, Default Method): Mention
-	`tramp-inline-compress-start-size'.  Remove "kludgy" phrase.
+	* tramp.texi (Inline methods, Default Method):
+	Mention `tramp-inline-compress-start-size'.  Remove "kludgy" phrase.
 	Remove remark about doubled "-t" argument.
 	(Auto-save and Backup): Remove reference to Emacs 21.
 	(Filename Syntax): Describe port numbers.
@@ -6056,7 +6061,7 @@
 2007-10-28  Kevin Greiner  <kevin.greiner@compsol.cc>
 
 	* gnus.texi (nntp-open-via-telnet-and-telnet): Fix grammar.
-	(Agent Parameters): Updated parameter names to match code.
+	(Agent Parameters): Update parameter names to match code.
 	(Group Agent Commands): Corrected 'gnus-agent-fetch-series' as
 	'gnus-agent-summary-fetch-series'.
 	(Agent and flags): New section providing a generalized discussion
@@ -6860,7 +6865,7 @@
 	(Tag searches): Document regular expression search for tags.
 	(Stuck projects): New section.
 	(In-buffer settings): New keywords.
-	(History and Acknowledgments): Updated description.
+	(History and Acknowledgments): Update description.
 
 2007-02-24  Alan Mackenzie  <acm@muc.de>
 
@@ -7092,7 +7097,7 @@
 	(Custom agenda views): Section completely rewritten.
 	(Summary): Compare with Planner.
 	(Feedback): More info about creating backtraces.
-	(Plain lists): Modified example.
+	(Plain lists): Modify example.
 	(Breaking down tasks): New section.
 	(Custom time format): New section.
 	(Time stamps): Document inactive timestamps.
diff --git a/doc/misc/flymake.texi b/doc/misc/flymake.texi
index f88bd95008..d1f3e21c20 100644
--- a/doc/misc/flymake.texi
+++ b/doc/misc/flymake.texi
@@ -311,6 +311,9 @@ Used when looking for a master file.  @xref{Locating a master file}.
 Patterns for error/warning messages in the form @code{(regexp file-idx
 line-idx col-idx err-text-idx)}.  @xref{Parsing the output}.
 
+@item flymake-warning-predicate
+Predicate to classify error text as warning. @xref{Parsing the output}.
+
 @item flymake-compilation-prevents-syntax-check
 A flag indicating whether compilation and syntax check of the same
 file cannot be run simultaneously.
diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 414650b065..ebed2e2de1 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,11 @@
+2013-06-21  Eduard Wiebe  <usenet@pusto.de>
+
+	Extend flymake's warning predicate to be a function (bug#14217).
+	* progmodes/flymake.el (flymake-warning-predicate): New.
+	(flymake-parse-line): Use it.
+	(flymake-warning-re): Make obsolete alias to
+	`flymake-warning-predicate'.
+
 2013-06-21  Stefan Monnier  <monnier@iro.umontreal.ca>
 
 	* emacs-lisp/package.el (package-alist): Include obsolete packages.
diff --git a/lisp/progmodes/flymake.el b/lisp/progmodes/flymake.el
index 99b48e8d0d..2ead734d16 100644
--- a/lisp/progmodes/flymake.el
+++ b/lisp/progmodes/flymake.el
@@ -1049,8 +1049,12 @@ from compile.el")
 ;;   :type '(repeat (string number number number))
 ;;)
 
-(defvar flymake-warning-re "^[wW]arning"
-  "Regexp matching against err-text to detect a warning.")
+(define-obsolete-variable-alias 'flymake-warning-re 'flymake-warning-predicate "24.4")
+(defvar flymake-warning-predicate "^[wW]arning"
+  "Predicate matching against error text to detect a warning.
+Takes a single argument, the error's text and should return non-nil
+if it's a warning.
+Instead of a function, it can also be a regular expression.")
 
 (defun flymake-parse-line (line)
   "Parse LINE to see if it is an error or warning.
@@ -1067,16 +1071,22 @@ Return its components if so, nil otherwise."
 	       (line-idx (nth 2 (car patterns))))
 
 	  (setq raw-file-name (if file-idx (match-string file-idx line) nil))
-	  (setq line-no       (if line-idx (string-to-number (match-string line-idx line)) 0))
+	  (setq line-no       (if line-idx (string-to-number
+                                            (match-string line-idx line)) 0))
 	  (setq err-text      (if (> (length (car patterns)) 4)
 				  (match-string (nth 4 (car patterns)) line)
-				(flymake-patch-err-text (substring line (match-end 0)))))
-	  (or err-text (setq err-text "<no error text>"))
-	  (if (and err-text (string-match flymake-warning-re err-text))
-	      (setq err-type "w")
-	    )
-	  (flymake-log 3 "parse line: file-idx=%s line-idx=%s file=%s line=%s text=%s" file-idx line-idx
-		       raw-file-name line-no err-text)
+				(flymake-patch-err-text
+                                 (substring line (match-end 0)))))
+	  (if (null err-text)
+              (setq err-text "<no error text>")
+            (when (cond ((stringp flymake-warning-predicate)
+                         (string-match flymake-warning-predicate err-text))
+                        ((functionp flymake-warning-predicate)
+                         (funcall flymake-warning-predicate err-text)))
+              (setq err-type "w")))
+	  (flymake-log
+           3 "parse line: file-idx=%s line-idx=%s file=%s line=%s text=%s"
+           file-idx line-idx raw-file-name line-no err-text)
 	  (setq matched t)))
       (setq patterns (cdr patterns)))
     (if matched
diff --git a/test/ChangeLog b/test/ChangeLog
index 90ea593a01..73ce74a02a 100644
--- a/test/ChangeLog
+++ b/test/ChangeLog
@@ -1,3 +1,11 @@
+2013-06-21  Eduard Wiebe  <usenet@pusto.de>
+
+	Test suite for flymake.
+	* automated/flymake-tests.el:
+	* automated/flymake/warnpred/Makefile
+	* automated/flymake/warnpred/test.c
+	* automated/flymake/warnpred/test.pl: New files.
+
 2013-06-12  Rüdiger Sonderfeld  <ruediger@c-plusplus.de>
 
 	* automated/reftex-tests.el (reftex-parse-from-file-test): Fix test.
diff --git a/test/automated/flymake-tests.el b/test/automated/flymake-tests.el
new file mode 100644
index 0000000000..6b68a956db
--- /dev/null
+++ b/test/automated/flymake-tests.el
@@ -0,0 +1,82 @@
+;;; flymake-tests.el --- Test suite for flymake
+
+;; Copyright (C) 2011-2013 Free Software Foundation, Inc.
+
+;; Author: Eduard Wiebe <usenet@pusto.de>
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; GNU Emacs is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;;; Code:
+(require 'ert)
+(require 'flymake)
+
+(defgroup flymake-tests nil
+  "Test suite for flymake.")
+
+
+;; Warning predicate
+(defun flymake-tests--current-face (file predicate)
+  (let ((buffer (find-file-noselect file)))
+    (unwind-protect
+        (with-current-buffer (find-file-noselect file)
+          (setq-local flymake-warning-predicate predicate)
+          (goto-char (point-min))
+          (flymake-mode 1)
+          ;; XXX: is this reliable enough?
+          (sleep-for (+ 0.5 flymake-no-changes-timeout))
+          (flymake-goto-next-error)
+          (face-at-point))
+      (and buffer (kill-buffer buffer)))))
+
+(ert-deftest warnining-predicate-rx-gcc ()
+  "Test GCC warning via regexp predicate."
+  :expected-result (if (executable-find "gcc") :passed :failed)
+  (should (eq 'flymake-warnline
+              (flymake-tests--current-face
+               "flymake/warnpred/test.c"
+               "^[Ww]arning"))))
+
+(ert-deftest warning-predicate-function-gcc ()
+  "Test GCC warning via function predicate."
+  :expected-result (if (and (executable-find "gcc") (executable-find "make"))
+                       :passed
+                     :failed)
+  (should (eq 'flymake-warnline
+              (flymake-tests--current-face
+               "flymake/warnpred/test.c"
+               (lambda (msg) (string-match "^[Ww]arning" msg))))))
+
+(ert-deftest warning-predicate-rx-perl ()
+  "Test perl warning via regular expression predicate."
+  :expected-result (if (executable-find "perl") :passed :failed)
+  (should (eq 'flymake-warnline
+              (flymake-tests--current-face
+               "flymake/warnpred/test.pl"
+               "^Scalar value"))))
+
+(ert-deftest warning-predicate-function-perl ()
+  "Test perl warning via function predicate."
+  :expected-result (if (executable-find "perl") :passed :failed)
+  (should (eq 'flymake-warnline
+              (flymake-tests--current-face
+               "flymake/warnpred/test.pl"
+               (lambda (msg) (string-match "^Scalar value" msg))))))
+
+(provide 'flymake-tests)
+
+;;; flymake.el ends here
diff --git a/test/automated/flymake/warnpred/Makefile b/test/automated/flymake/warnpred/Makefile
new file mode 100644
index 0000000000..33af51c333
--- /dev/null
+++ b/test/automated/flymake/warnpred/Makefile
@@ -0,0 +1,8 @@
+# Makefile for flymake tests
+
+CC_OPTS = -Wall
+
+check-syntax:
+	$(CC) $(CC_OPTS) ${CHK_SOURCES}
+
+# eof
diff --git a/test/automated/flymake/warnpred/test.c b/test/automated/flymake/warnpred/test.c
new file mode 100644
index 0000000000..3a3926131f
--- /dev/null
+++ b/test/automated/flymake/warnpred/test.c
@@ -0,0 +1,5 @@
+int main()
+{
+  char c = 1000;
+  return c;
+}
diff --git a/test/automated/flymake/warnpred/test.pl b/test/automated/flymake/warnpred/test.pl
new file mode 100644
index 0000000000..2013b2e443
--- /dev/null
+++ b/test/automated/flymake/warnpred/test.pl
@@ -0,0 +1,2 @@
+@arr = [1,2,3,4];
+@arr[1] = -1;