As of Sept 14, 2016, Bitbucket does not support .gitattributes diff in regards to being able to diff text files that git detects as binary. This means that using Bitbucket, we are unable to see the changes made to certain text files since Bitbucket treats them as binary files.

Example:

*.dnh diff

This functionality has been present in git since 2012, and Bitbucket still does not support it.