When applying the command Replace all with marked text, error happens

[Lam]

I have an ebook (Test.epub attached) with a list as follows:

 <p class="block">Day la vi du</p>
 <ol class="list">
 <li class="block1">List 1</li>
 <li class="block2">List 2</li>
 <li class="block2">List 3</li>
 <li class="block3">List 4</li>
</ol>

I would like to change block1,2,3,4 into block 2p, so I mark the whole block of list (including the line <ol class="list1">). Then I apply the command replace all as follow:

Find: block\d+
Replace with: block2p
Mode: Regex
Scope: marked text

After allying the command Replace all, the line <ol class="list"> has been changed into </ol>. Pls see picture pic2.png attached.
But If the marked text does not include line <ol class="list"> or </ol>, error does not happen. Pls see pictures pic3.png and pic4.png

Version: Calibre 1.45
Operating System: Windows 8.1

[Lam (lamkiet)]

I forgot attaching the file Test.epub.

[Kovid Goyal (kovid)]

Fixed in branch master. The fix will be in the next release. calibre is usually released every Friday.

 status fixreleased