Notebook history does not handle single new line

[mehmetoguzderin]

Revision browser does not show one new empty line as difference. The new line is detected correctly, saved but the difference is not visible in the revision browser, instead it only shows "Expand x lines ..." option. There are no problems with more than one empty new lines.

Steps to Reproduce

• Create a new notebook
• Add a single new line anywhere
• Check notebook history

Cause of the Problem

This problem is caused by the handling of diff module's output by react-diff-viewer module at constructLines function in compute-lines.js. If emptiness check and first-last modification disabled, behavior matches the expectation (Iodide system registers those new lines as change, as it should be). react-diff-viewer provides no way to change this behavior.

[wlach]

This sounds like a bug in react-diff-viewer, if you wanted to provide a test case and a PR there, we could pick up the fix on their next release.

[bcolloran]

@wlach @mehmetoguzderin created a new issue #2275 about moving off of react-diff-viewer. just posting here as an fyi since you guys are looking at the diff viewer stuff. @mehmetoguzderin if this is of interest to you, you'd be very welcome to give it a shot.

[mehmetoguzderin]

@wlach @mehmetoguzderin created a new issue #2275 about moving off of react-diff-viewer. just posting here as an fyi since you guys are looking at the diff viewer stuff. @mehmetoguzderin if this is of interest to you, you'd be very welcome to give it a shot.

I think I can try it out!