Provide human friendly message instead of `fatal: --local can only be used inside a git repository`

[jsoref]

This run managed to create a .git directory containing a single file (reporter.json):

https://github.com/jsoref/examples-testing/runs/5404530182?check_suite_focus=true#step:4:20

Download action repository 'actions/checkout@v2' (SHA:ec3a7ce113134d7a93b817d10a8272cb61118579)
...
Run actions/checkout@v2
  with:
    repository: jsoref/examples-testing
    token: ***
    ssh-strict: true
    persist-credentials: true
    clean: true
    fetch-depth: 1
    lfs: false
    submodules: false
  env:
    PR_HEAD_SHA: 2f3e6fc9852caf53e728702a7adf0e871e2e1531
    result_code: 
Syncing repository: jsoref/examples-testing
Getting Git version info
/usr/bin/git config --local --get remote.origin.url
Error: fatal: --local can only be used inside a git repository
Deleting the contents of '/home/runner/work/examples-testing/examples-testing'

Which triggers:

checkout/src/git-command-manager.ts

Line 365 in ec3a7ce

['config', '--local', '--get', 'remote.origin.url'],

The message:

Error: fatal: --local can only be used inside a git repository

... is not particularly helpful to most people.

In this code path, what it means is:

There was a .git directory where the checkout was trying to operate, but it wasn't a valid .git repository.

The next log output line is fine:

Deleting the contents of '/home/runner/work/examples-testing/examples-testing'

[stmcginnis]

I am seeing similar behavior with a job that does the checkout, runs a script, then tries to use git update-index. I get the error:

+ git update-index --assume-unchanged cmd/cli/plugin/pinniped-auth/asset/pinniped-v0.4.4
fatal: not a git repository (or any of the parent directories): .git

I thought at first this might be a side effect of the default shallow clone, so I tried adding:

with:
   fetch-depth: 0

As indicated in the README to get the full history. But no difference in behavior.

[jsoref]

My guess is that it's from this:

checkout/src/git-directory-helper.ts

Lines 28 to 33 in ec3a7ce

	!fsHelper.directoryExistsSync(path.join(repositoryPath, '.git')) ||
	repositoryUrl !== (await git.tryGetFetchUrl())
	) {
	remove = true
	} else {
	// Delete any index.lock and shallow.lock left by a previously canceled run or crashed git process

The boolean logic is giving me a headache.

[jsoref]

Ok, figured it out.

Here's the debugging showing what happened:
https://github.com/jsoref/examples-testing/runs/5497620370?check_suite_focus=true#step:4:1

Run jsoref/check-spelling@prerelease
-- this added a file into a .git/ directory

Run actions/checkout@v3
Getting Git version info
Working directory is '/home/runner/work/examples-testing/examples-testing'
/usr/bin/git version
git version 2.35.1
/usr/bin/git config --local --get remote.origin.url
Error: fatal: --local can only be used inside a git repository

[Koushikrad]

@jsoref , am facing the same error in checkout actions. Is this fixed? Is there a recommended fix or workaround for this?

[jsoref]

@Koushikrad: before you run your checkout action, do a find .:
https://github.com/jsoref/examples-testing/blob/77f41bc266cf5fe28fdbddc68f83cfd57a48b4fe/.github/workflows/spelling.yml#L130-L131

You'll probably see that there's a file that's squatting in a mostly empty .git directory.

[Koushikrad]

@jsoref , yes when I added find . am seeing a lot of files being listed. They are mostly my external dependencies from my project. Can you kindly help what i should be doing about those files? and how they related to the fatal error?

[jsoref]

It's almost certainly a sequencing order. You're probably doing something before the checkout step that you should be doing after.

Fwiw, from memory fatal is somewhat inaccurate, in that, I'm pretty sure it just shoots everything and moves on w/ life w/o actually killing your job...