Add Overwrite Support For github_repository_file

[jcudit]

Fixes https://github.com/terraform-providers/terraform-provider-github/issues/438

/cc @techdragon @shoekstra @cornfeedhobo

[jcudit]

I went down the path of removing references to "test-repo" and leveraging a per-test generated repository instead. Those changes turned out to break tests so I've opted to leave the existing code paths alone and expose testAccCheckGithubRepositoryFileExistsWithRepo instead. This allows for creating a repository from a template and overwriting its files during the test suite.

[anGie44]

do we expect the behavior of the overwrite to extend to updates as well? i'm thinking in the event we create a new file (assuming it doesn't already exist in a repo), if we go to update the config and overwrite is omitted or even explicitly set to false, the file will still get updated in place

[anGie44]

the global testOrganization could also be used here

[jcudit]

Thanks for raising discussion on the update case. I had not given it too much thought.

After thinking about this a bit, I recommend we rebrand overwrite to overwrite_on_create.
We can then assume that whenever the update code path is executed, we will always be overwriting a file, which matches the existing implementation.

To further safeguard, we can add the ForceNew attribute to overwrite_on_create so that if configuration changes, we can start fresh with a new file. What do you think @anGie44 ?

[jcudit]

q

[jaxxstorm]

Is there any news on when this might be reviewed/merged?

[anGie44]

I recommend we rebrand overwrite to overwrite_on_create.

I like this idea, suits the intended behavior 👍 my only hesitation would be adding the ForceNew attribute since the field is intended to be used only at create time and it might be more of a pain point to force recreation for users

[jcudit]

Tests are looking good. The GHES ones are failing as the infrastructure is down at the moment.