very large diffs in merge proposals frustrate the user

[Robert Collins]

When a huge MP diff occurs it gets truncated (not sure why) - but when its truncated a few irritations occur.

Firstly, if I've reviewed all the diff I find out at the end that it got truncated, I need to switch to a different process to finish reviewing it.

Secondly having to switch to a different way of doing the review is jarring.

Somethings that would make this nicer:
 - where the 'download diff' link is, mention that the displayed one is truncated
 - provide another download link at the bottom of the diff (so that when folk miss the warning they can download it directly)
 - possible mention in the metadata at the top that its very long, truncated and downloadable.

[Mike Pontillo (mpontillo)]

Five years later, it feels like rendering another twice as many lines of diff should not be an issue for a modern browser. So I think a quick fix might be to simply increase the threshold from 5000 to 10000. I just hit this with a ~7500 line branch.

For what it's worth, the largest diff I've seen (or rather, not seen) was ~40000 lines; merging a large feature branch into MAAS.

[Mike Pontillo (mpontillo)]

Also, since this makes it impossible to review large diffs in-context, I think it should be higher priority than a "Low".