Checkmate: Error description confusing

[Former user]

Original issue 439 created by [e-mail] on 2015-01-30T07:54:40.000Z:

What steps will reproduce the problem?
1. Add the following check rule:
Source pattern: \x0a (or alternatively \x0d OR \x0d\x0a)
Target pattern: <same>
Description: "Line Break missing"
2. Run the rules on a TMX file where a line break is missing in the target.

What is the expected output? What do you see instead?
The source part "\x0a" ist not in the target (from rule: Line Break missing").

Instead I see:
The source part "" ist not in the target (from rule: Line Break missing").

It seems as if the regular expression is not displayed in the message. I only have this phenomenon with the expressions metioned above. Others work fine

What version of the product are you using? On what operating system?
0.26, Windows 7

[Former user]

Comment 1. originally posted by @ysavourel on 2015-03-06T19:32:57.000Z:

[Former user]

Comment 2. originally posted by @ysavourel on 2015-03-06T19:53:40.000Z:

Fixed (commit 0382c1c5f873). The literal line break that was missing was ending up in the issue message, and this broke the CheckMate display.

One caveat -- we can't distinguish between patterns that use \x0a versus those that use other forms like \n (ditto for \x0d). So the error message we produce now escapes the U+000A as '\n' and U+000D as '\r', since those forms are slightly more recognizable.