react-native-git-upgrade does not respect android package name

Is this a bug report?

Yes

Have you read the Contributing Guidelines?

Yes

Environment

Environment:
  OS:  Linux 4.10
  Node:  6.10.3
  Yarn:  1.1.0
  npm:  3.10.10
  Watchman:  4.7.0
Error: unable to print environment info
{ Error: not found: xcodebuild
    (snip stacktrace)

Steps to Reproduce

1. Run react-native init MyProject --version 0.48.3
2. Rename your com.myproject package / applicationId to com.my.new.project according to this SO answer: https://stackoverflow.com/a/37390022/543864
3. Run react-native-git-upgrade to upgrade to 0.49.1 (or higher) which failes silently like described in #12112

There is a similar issue #11163 from when MainApplication.java was introduced in 0.29.

Expected Behavior

Running react-native-git-upgrade in step 3 uses the current Android package name by either parsing AndroidManifest.xml or accepting the package name as a param (ie. react-native-git-upgrade --package com.my.new.project and patches MainApplication.java in the correct path (ie. com/my/new/project).

It looks like react-native init took a package param in version 0.38 which was later removed. That code could be used as a basis for either a --package option to react-native-git-upgrade or parsing AndroidManifest.xml. What is the best approach?

Actual Behavior

Running react-native-git-upgrade in step 3 fails silently like described in #12112 because it tried to patch a file that is not in the git index. It tried to patch com/myproject/MainApplication.java instead of com/my/new/project/MainApplication.java.

Reproducible Demo

Follow the steps under Steps to Reproduce.

[nikolaik]

My workaround (this time) was to copy my existing MainApplication.java to the path react-native-git-upgrade expects, run the upgrade and then copy the file back to the correct path.

[jordanmkoncz]

I’m experiencing the same issue as I changed my Android package name to be in the form com.companyname.appname instead of the default form com.appname that react-native init generates.

@SirNeuman react-native-git-upgrade gets the package name by looking at the name value in your package.json. It assumes that this matches the name of your app, and then it also assumes that your Android package name is still in the form that it was when the project was generated, i.e. com.appname.

It seems like it should be possible to update react-native-git-upgrade so that it is able to figure out your actual package name; it could just pull this from your android/app/src/main/AndroidManifest.xml file since the location of that file does not change (unlike the location of the MainApplication.java file) and the manifest node has a package attribute with the correct value of the Android package name.

In the meantime, I was also able to use the workaround posted by @nikolaik.