git-upgrade fails if email is not set global for git

Is this a bug report?

yes

Have you read the Contributing Guidelines?

no

Environment

Environment: OS: Linux 4.13 Node: 9.5.0 Yarn: Not Found npm: 5.6.0 Watchman: Not Found Xcode: N/A Android Studio: 3.0 AI-171.4443003

Packages: (wanted => installed) react: ^16.2.0 => 16.2.0 react-native: ^0.53.2 => 0.53.2

Steps to Reproduce

1. Do not setup your email for git globally
2. But do setup your git email for the local project
3. run react-native-git-upgrade

Expected Behavior

no errors

Actual Behavior

$ git commit -m "Project snapshot"
On branch master
nothing to commit, working directory clean
$ react-native-git-upgrade 
git-upgrade info Check for updates 
...
git-upgrade info Add all files to commit 
git-upgrade info Commit current project sources 

*** Please tell me who you are.
Run
git config --global user.email "[e-mail]"
git config --global user.name "Your Name"

to set your account's default identity.
Omit --global to set the identity only in this repository.

fatal: unable to auto-detect email address (got 'locus@cobalt.(none)')
git-upgrade ERR! An error occurred during upgrade: 
git-upgrade ERR! Error: Command 'git commit -m "Project snapshot"' exited with code 128:
stderr: undefined
...

If I setup my email per git config --global user.email ... there are no errors.

It seems that git runs within react-native-git-upgrade differently compared to in the shell.

[grabbou]

Reopening, since “react-native-git-upgrade” is still part of this repository.

[thymikee]

We’re deprecating react-native-git-upgrade in favor of react-native upgrade using https://github.com/react-native-community/rn-diff-purge/ under the hood since RN 0.59.0. Please try that 😃