This bug appears to have been reported against 'rawhide' during the Fedora 26 development cycle.
Changing version to '26'.

I cannot reproduce an extra white spaces anywhere and output is identical to yum. Therefore I can close it. Tested with dnf-2.5.1.

repo id                                                                                        repo name                                                                                                           
bumblebee-nonfree-unmanaged-source                                                             bumblebee nonfree unmanaged for fedora Linux 27 - x86_64 - Source                                                   
bumblebee-source                                                                               bumblebee for fedora Linux 27 - x86_64 - Source                                                                     
fedora                                                                                         Fedora 27 - x86_64                                                                                                  
...

if you will compare output to `repolist all`, it doesn't add any extra whitespaces in there..

This issue is cosmetic and should be fixed one day (most probably with switching to libsmartcols for printing tables)

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This bug appears to have been reported against 'rawhide' during the Fedora 29 development cycle.
Changing version to '29'.

It's a cosmetic issue we're not going to fix in the current codebase.
It will get fixed once we switch from output.py to a new code, possibly based on smartcols.