Prevent React hook call warnings when used with MDX

.changeset/tame-seas-sort.md

@@ -0,0 +1,9 @@
+---
+'astro': patch
+---
+
+Prevent React hook call warnings when used with MDX
+
+When React and MDX are used in the same project, if the MDX integration is added before React, previously you'd get a warning about hook calls.
+
+This makes it so that the MDX integration's JSX renderer is last in order.

packages/astro/src/integrations/index.ts

@@ -73,6 +73,7 @@ export async function runHookConfigSetup({
 	let updatedConfig: AstroConfig = { ...settings.config };
 	let updatedSettings: AstroSettings = { ...settings, config: updatedConfig };
 	let addedClientDirectives = new Map<string, Promise<string>>();
+	let astroJSXRenderer: AstroRenderer | null = null;
 
 	for (const integration of settings.config.integrations) {
 		/**
@@ -103,7 +104,11 @@ export async function runHookConfigSetup({
 						throw new Error(`Renderer ${bold(renderer.name)} does not provide a serverEntrypoint.`);
 					}
 
-					updatedSettings.renderers.push(renderer);
+					if(renderer.name === 'astro:jsx') {
+						astroJSXRenderer = renderer;
+					} else {
+						updatedSettings.renderers.push(renderer);
+					}
 				},
 				injectScript: (stage, content) => {
 					updatedSettings.scripts.push({ stage, content });
@@ -174,6 +179,11 @@ export async function runHookConfigSetup({
 		}
 	}
 
+	// The astro:jsx renderer should come last, to not interfere with others.
+	if(astroJSXRenderer) {
+		updatedSettings.renderers.push(astroJSXRenderer);
+	}
+
 	updatedSettings.config = updatedConfig;
 	return updatedSettings;
 }

packages/integrations/mdx/test/fixtures/mdx-plus-react/astro.config.mjs

@@ -2,5 +2,5 @@ import mdx from '@astrojs/mdx';
 import react from '@astrojs/react';
 
 export default {
-	integrations: [react(), mdx()]
+	integrations: [mdx(), react()]
 }

packages/integrations/mdx/test/fixtures/mdx-plus-react/src/components/Component.jsx

@@ -1,5 +1,8 @@
+import { useState } from "react";
+
 const Component = () => {
-  return <p>Hello world</p>;
+	const [name] = useState('world');
+  return <p>Hello {name}</p>;
 };
 
 export default Component;

packages/integrations/mdx/test/fixtures/mdx-plus-react/src/pages/post.mdx

@@ -0,0 +1,3 @@
+# Testing
+
+This works!

packages/integrations/mdx/test/mdx-plus-react.test.js

@@ -2,13 +2,27 @@ import { expect } from 'chai';
 import { parseHTML } from 'linkedom';
 import { loadFixture } from '../../../astro/test/test-utils.js';
 
+function hookError() {
+	const error = console.error;
+	const errors = [];
+	console.error = function(...args) {
+		errors.push(args);
+	};
+	return () => { 
+		console.error = error;
+		return errors;
+	};
+}
+
 describe('MDX and React', () => {
 	let fixture;
+	let unhook;
 
 	before(async () => {
 		fixture = await loadFixture({
 			root: new URL('./fixtures/mdx-plus-react/', import.meta.url),
 		});
+		unhook = hookError();
 		await fixture.build();
 	});
 
@@ -20,4 +34,16 @@ describe('MDX and React', () => {
 
 		expect(p.textContent).to.equal('Hello world');
 	});
+
+	it('mdx renders fine', async () => {
+		const html = await fixture.readFile('/post/index.html');
+		const { document } = parseHTML(html);
+		const h = document.querySelector('#testing');
+		expect(h.textContent).to.equal('Testing');
+	});
+
+	it('does not get a invalid hook call warning', () => {
+		const errors = unhook();
+		expect(errors).to.have.a.lengthOf(0);
+	});
 });