Not sure how you guys feel about this, no worries if it's not wanted for some reason.
Anyway, it was kind of low-level annoying last week when I ran cargo fmt and a bunch of files unrelated to my changes were also updated. If we run it in CI it makes it easier to stay on top of things is all I'm thinking.
There is a slight hack in the CI script because --write-mode=diff doesn't exit with an error code when there are diffs, so I added an explicit exit to make it fail. That's just a temporary measure until we can use --check in stable.
Just to prove that it actually fails when there are diffs, you can see the failing build for 58f5481 here:
https://travis-ci.org/philbooth/syncstorage-rs/builds/410320506
And here is the follow-up build for 80e4471 with the fixes:
https://travis-ci.org/philbooth/syncstorage-rs/builds/410321703