epubs export with series number changed from 0 to 1

[Matthew Coyne]

I have any epub in calibre. I can do this with any old or brand new generated epubs and have had a friend replicate it with their own files. I edit the metadata to set a series name, and a index of 0. I use the Polish tool to save the metadata directly to the epub.

If I at this point go to the epub file in my calibre library folder, unzip it and open the opf file, I will find a line reading:

<meta refines="#id-3" property="group-position">0.0</meta>

If I then use Save to Disk or Send to Device on the file, go to where the new epub file was created, unzip it and open the opf file, I will find a line instead reading:

<opf:meta refines="#id-3" property="group-position">1</opf:meta>

Other numbers I've tried work fine, just 0 gets changed.

calibre version: 7.18
OS: Windows 10 Pro

[Kovid Goyal (kovid)]

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