Read project settings from package.json

[friederbluemle]

Options such as --reserve-builds change the version code every command compares against or writes, so they had to be repeated on each call. Forgetting one silently checks against the wrong code or, with --write, writes a lower code than the native files already hold. Settings that are permanent for a project can now live in package.json:

{
  "rn-version-sync": {
    "reserveBuilds": 100
  }
}

• Six settings, one per option. reserveBuilds, gradlePath, pbxprojPath, configuration, skipAndroid and skipIos map to the flags of the same name. Per-invocation flags (--write, --version-name, --version-code, the --print* family and --format) stay command line only.
• A command line option takes precedence over the configured value, including an explicit skip flag over a configured one. Relative paths are resolved against the project directory, like the flags.
• Mistakes fail loudly. An unknown setting lists the valid names (so reserveBuild is caught), a value of the wrong type names the expected type, and a key that is not an object is rejected. A missing package.json means no configuration, so --version-name plus --version-code keep working without one.
• The library applies the configuration too. checkVersions, syncVersions, resolveVersions, readNativeValues and formatTemplate fill in options that are not passed explicitly, so syncVersions(dir) from a script and the CLI agree. loadConfig and the ProjectConfig type are exported, and SyncOptions now extends ProjectConfig.
• The table honors the configured configuration. The iOS row reads ios (Staging) whether the configuration comes from the flag or from package.json.
• --help and README document the key, the settings table and the precedence rule; the --reserve-builds row points to it.

package.json is the usual place for small tool configuration in the npm ecosystem, and the tool already reads it, so no new file, lookup or dependency is needed. Deferred for now: an rc file as an alternative location, and a guard that refuses to write a lower version code than the native files hold.

[github-actions]

🎉 Released in v0.8.0