Add a "check up to date" for use in CI

[davidmorgan]

There should be a way for build_runner to notice and report whether it changed anything, so that a CI can check generated files are up to date.

[lazytesting]

Would be a great feature indeed. What we currently do as a workaround is:

dart build_runner build

if ! git diff --quiet; then
  echo "changes found after running build runners"
  git diff --name-only
  git status
  exit 1
else
  echo "no changes found after running build runners"
fi

[rrousselGit]

There's build_verify. It's a unit test that verifies codegen is up-to-date, which achieves similar effects