USAGE.md

Using rn-diff-purge

The git patches can be used as a replacement of react-native-git-upgrade. The procedure is straightforward and more trusted than using the upgrade command.

Recommended method

1 Check the diff

Check the diff of your current version and the release you want to upgrade to.

2 Manually do the changes

Do the changes from the diff in your project.
They are usually no more than 10 lines, so it's pretty quick and easy.
If it's more than that, you could try the alternative method below.
⚠️ In any case, make sure you pay attention to the changes made. It's always imporant to know what an upgrade actually changed.

Alternative method (using patch)

1 Download the git patch

Download the patch for your version, for example:

curl https://github.com/react-native-community/rn-diff-purge/compare/release/0.29.0...release/0.30.0.diff > upgrade-rn.patch

2 Prepare the patch

The patch is made for the RnDiffApp located in the RnDiffApp folder of this repository. To use it in your own repository, some changes are needed.

Don't worry about the root folder RnDiffApp, it can be ignored with the option -p 2 (see https://git-scm.com/docs/git-apply)

Then, some files include the name of the app in their path:

• All files in the ios directory (example: ios/RnDiffApp/AppDelegate.m)
• Some files in the android directory (example: android/app/src/main/java/com/rndiffapp/MainActivity.java)

You have to edit the patch and replace all occurences of ios/RnDiffApp and com/rndiffapp by the name of your app.

3 Set up the 3-way merge

By default in case of conflicts, the git apply command will fail and leave the files untouched. It could be interesting to fallback on a 3-way merge (option --3way) in order to resolve the conflicts with your favorite merge tool.

To do this, git needs to know the blob referenced in the patch (line index 4c88077..e49e881 100644 for example). So you have to add rn-diff as a remote repository and fetch it (see this SO question for details).

git remote add rn-diff-purge https://github.com/react-native-community/rn-diff-purge.git
git fetch rn-diff-purge

4 Run the apply command

git apply upgrade-rn.patch --exclude=package.json -p 2 --3way

Wrap up

# Download the patch
curl https://github.com/react-native-community/rn-diff-purge/compare/release/0.29.0...release/0.30.0.diff > upgrade-rn.patch

# Replace RnDiffApp occurences
appNameCamelCase=MyApp
appNameLowerCase=myapp
sed -i "" "s-ios/RnDiffApp-ios/${appNameCamelCase}-" upgrade-rn.patch
sed -i "" "s-java/com/rndiffapp-java/com/${appNameLowerCase}-" upgrade-rn.patch

# Set up the 3-way merge
git remote add rn-diff-purge https://github.com/react-native-community/rn-diff-purge.git
git fetch rn-diff-purge

# Run the apply command
git apply upgrade-rn.patch --exclude=package.json -p 2 --3way

⚠️ Known issues

Sometimes there are new files that reference the project's name. Whenever there is a new file, make sure to check for this, and replace it with your project's name.