Add warnings if multiple JSX renderers are used

.changeset/strong-games-travel.md

@@ -0,0 +1,7 @@
+---
+'@astrojs/preact': patch
+'@astrojs/react': patch
+'@astrojs/solid-js': patch
+---
+
+Added a warning message when multiple UI frameworks are being used without either the `include` or `exclude` property being set on the integration.

packages/integrations/preact/src/index.ts

@@ -71,6 +71,14 @@ export default function ({ include, exclude, compat, devtools }: Options = {}):
 					injectScript('page', 'import "preact/debug";');
 				}
 			},
+			'astro:config:done': ({ logger, config }) => {
+				const knownJsxRenderers = ['@astrojs/react', '@astrojs/preact', '@astrojs/solid-js'];
+				const enabledKnownJsxRenderers = config.integrations.filter((renderer) => knownJsxRenderers.includes(renderer.name));
+
+				if (enabledKnownJsxRenderers.length > 1 && !include && !exclude) {
+					logger.warn('More than one JSX renderer is enabled. This will lead to unexpected behavior unless you set the `include` or `exclude` option. See https://docs.astro.build/en/guides/integrations-guide/preact/#combining-multiple-jsx-frameworks for more information.');
+				}
+			}
 		},
 	};
 }

packages/integrations/react/src/index.ts

@@ -110,6 +110,14 @@ export default function ({
 					injectScript('before-hydration', preamble);
 				}
 			},
+			'astro:config:done': ({ logger, config }) => {
+				const knownJsxRenderers = ['@astrojs/react', '@astrojs/preact', '@astrojs/solid-js'];
+				const enabledKnownJsxRenderers = config.integrations.filter((renderer) => knownJsxRenderers.includes(renderer.name));
+
+				if (enabledKnownJsxRenderers.length > 1 && !include && !exclude) {
+					logger.warn('More than one JSX renderer is enabled. This will lead to unexpected behavior unless you set the `include` or `exclude` option. See https://docs.astro.build/en/guides/integrations-guide/react/#combining-multiple-jsx-frameworks for more information.');
+				}
+			}
 		},
 	};
 }

packages/integrations/solid/src/index.ts

@@ -107,6 +107,14 @@ export default function (options: Options = {}): AstroIntegration {
 					injectScript('page', 'import "solid-devtools";');
 				}
 			},
+			'astro:config:done': ({ logger, config }) => {
+				const knownJsxRenderers = ['@astrojs/react', '@astrojs/preact', '@astrojs/solid-js'];
+				const enabledKnownJsxRenderers = config.integrations.filter((renderer) => knownJsxRenderers.includes(renderer.name));
+
+				if (enabledKnownJsxRenderers.length > 1 && !options.include && !options.exclude) {
+					logger.warn('More than one JSX renderer is enabled. This will lead to unexpected behavior unless you set the `include` or `exclude` option. See https://docs.astro.build/en/guides/integrations-guide/solid-js/#combining-multiple-jsx-frameworks for more information.');
+				}
+			}
 		},
 	};
 }