Preserve face text properties in comint prompt.

Fixes: debbugs:20084

* lisp/font-lock.el (font-lock--remove-face-from-text-property): New
function.  Adapted from the previously commented out
remove-single-text-property.
Remove previously unused and commented out auxiliary function
remove-text-property and obsolete comment.
* lisp/comint.el (comint-output-filter): Use it to remove
comint-highlight-prompt.
(comint-snapshot-last-prompt, comint-output-filter): Use
font-lock-prepend-text-property for comint-highlight-prompt.
* test/automated/textprop-tests.el: New file.
(textprop-tests-font-lock--remove-face-from-text-property): New test.

Thus, the original face text property of a prompt "candidate" (the
last line of an output chunk not ending with a newline) is
preserved.  This amends the fix for bug#14744.

1 files changed, 5 insertions, 0 deletions

diff --git a/test/ChangeLog b/test/ChangeLog
index a9cad319ead..30b88412468 100644
--- a/test/ChangeLog
+++ b/test/ChangeLog
@@ -1,3 +1,8 @@
+2015-03-27  Wolfgang Jenkner  <wjenkner@inode.at>
+
+        * automated/textprop-tests.el: New file.
+        (textprop-tests-font-lock--remove-face-from-text-property): New test.
+
 2015-03-24  Michael Albinus  <michael.albinus@gmx.de>
 
         * automated/tramp-tests.el (tramp-test18-file-attributes)