feat(core): Support SENTRY_ENVIRONMENT env variable in Expo config plugin

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: antonis

CHANGELOG.md

@@ -24,12 +24,14 @@
 - Adds tags with Expo Updates context variables to make them searchable and filterable ([#5788](https://github.com/getsentry/sentry-react-native/pull/5788))
 - Add `environment` option to the Expo config plugin for native init ([#5796](https://github.com/getsentry/sentry-react-native/pull/5796))
   - Sets the environment in `sentry.options.json` during `expo prebuild`, so pre-JS crashes are tagged correctly
+  - Reads from the `environment` plugin prop or the `SENTRY_ENVIRONMENT` environment variable
   ```json
   ["@sentry/react-native/expo", {
     "useNativeInit": true,
     "environment": "staging"
   }]
   ```
+  - Or via `SENTRY_ENVIRONMENT` env variable (e.g. per EAS Build profile in `eas.json`)
 
 ### Fixes
 

packages/core/plugin/src/withSentry.ts

@@ -28,8 +28,9 @@ const withSentryPlugin: ConfigPlugin<PluginProps | void> = (config, props) => {
   }
 
   let cfg = config;
-  if (props?.environment) {
-    cfg = withSentryOptionsEnvironment(cfg, props.environment);
+  const environment = props?.environment || process.env.SENTRY_ENVIRONMENT;
+  if (environment) {
+    cfg = withSentryOptionsEnvironment(cfg, environment);
   }
   if (sentryProperties !== null) {
     try {