Provide an option to fetch renamed configuration file?

[fbiville]

27 still leaves an edge case unsolved: a configuration file renamed between two runs will cause headache to fail.

To work around the fact that Git does not follow renames in files' history, headache could offer an extra option such as --last-run-configuration-filename (hopefully a better name will emerge 😋) to specify the lost name of the configuration file at the last headache run revision.

If so, this should be validated, i.e. at least make sure the configuration file exists at the last run revision .

[fbiville]

https://github.com/fbiville/headache/issues/27 offers a solution to that problem that does not require an extra option.