tildify.el: Fix end-regex building in `tildify-find-env'

* lisp/textmodes/tildify.el (tildify-find-env): The
`tildify-ignored-environments-alist' allows the end-regex
to be provided not as a static string but mix of strings and
indexes of groups matched the begin-regex.  For example, the
“\verb!…!” TeX-command (where “!” is an arbitrary character)
is handled using:

    ("\\\\verb\\*?\\(.\\)" . (1))

In the same way, the following should be supported as well:

    ("open-\\(.\\)" . ("end-" 1))

However the tildify-find-env function fails at

    (concat result
            (if (stringp (setq aux (car expression)))
                 expression  ; BUG: expression is a list
               (regexp-quote (match-string aux))))

where the string part is handled incorrectly.

The most trivial fix would be to replace `expression'
in the true-part of the if-statement with `aux', but
instead, this commit optimises `tildify-find-env' by
changing it to use `mapconcat' rather than open-coded
while-loop.

* tests/automated/tildify-tests.el (tildify-test-find-env-end-re-bug):
New test validating fix to the above bug.

2 files changed, 17 insertions, 0 deletions

diff --git a/test/ChangeLog b/test/ChangeLog
index b6b3dd379a7..db32aae578b 100644
--- a/test/ChangeLog
+++ b/test/ChangeLog
@@ -1,3 +1,9 @@
+2014-06-05  Michal Nazarewicz  <mina86@mina86.com>
+
+        * automated/tildify-tests.el (tildify-test-find-env-end-re-bug): New
+        test checking end-regex building in `tildify-find-env' function when
+        integers (denoting capture groups) and strings are mixed together.
+
 2014-06-02  Michael Albinus  <michael.albinus@gmx.de>
 
         * automated/tramp-tests.el (tramp-remote-process-environment): Declare.
diff --git a/test/automated/tildify-tests.el b/test/automated/tildify-tests.el
index 4223029f626..25e9f22adf3 100644
--- a/test/automated/tildify-tests.el
+++ b/test/automated/tildify-tests.el
@@ -101,6 +101,17 @@ latter is missing, SENTENCE will be used in all placeholder positions."
                         (tildify-test--example-tex sentence sentence)
                         (tildify-test--example-tex sentence with-nbsp))))
 
+
+(ert-deftest tildify-test-find-env-end-re-bug ()
+    "Tests generation of end-regex using mix of indexes and strings"
+  (with-temp-buffer
+    (let ((tildify-ignored-environments-alist
+           `((,major-mode ("foo\\|bar" . ("end-" 0))))))
+      (insert "foo whatever end-foo")
+      (goto-char (point-min))
+      (should (string-equal "end-foo" (tildify-find-env "foo\\|bar"))))))
+
+
 (provide 'tildify-tests)
 
 ;;; tildify-tests.el ends here