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test/README.md

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+# Testing
+
+## Testing multiple versions of React
+
+You can check integration of different versions of React (for example different [release channels](https://react.dev/community/versioning-policy) or PRs to React) by running the following commands:
+
+1. `node scripts/useReactVersion.mjs <version>`.
+
+   Possible values for `version`:
+
+   - default: `stable` (minimum supported React version)
+   - a tag on npm, for example `next`, `experimental` or `latest`
+   - an older version, for example `^17.0.0`
+
+2. `pnpm install`
+
+### CI
+
+#### `next` version
+
+For `react@next` specifically, there's a `react-next` workflow in our CircleCI pipeline that you can trigger in CircleCI on the PR you want to test:
+
+1. Go to https://app.circleci.com/pipelines/github/mui/mui-x?branch=pull/PR_NUMBER and replace `PR_NUMBER` with the PR number you want to test.
+2. Click `Trigger Pipeline` button.
+3. Expand `Add parameters (optional)` and add the following parameter:
+
+   | Parameter type | Name       | Value        |
+   | :------------- | :--------- | :----------- |
+   | `string`       | `workflow` | `react-next` |
+
+4. Click `Trigger Pipeline` button.
+
+#### Other versions
+
+You can pass the same `version` to our CircleCI pipeline as well:
+
+With the following API request we're triggering a run of the default workflow in
+PR #24289 for `react@next`
+
+```bash
+curl --request POST \
+  --url https://circleci.com/api/v2/project/gh/mui/material-ui/pipeline \
+  --header 'content-type: application/json' \
+  --header 'Circle-Token: $CIRCLE_TOKEN' \
+  --data-raw '{"branch":"pull/24289/head","parameters":{"react-version":"next"}}'
+```