feat(client-redirects): make plugin respect onDuplicateRoutes config

packages/docusaurus-plugin-client-redirects/src/__tests__/collectRedirects.test.ts

@@ -9,18 +9,21 @@ import {removeTrailingSlash} from '@docusaurus/utils';
 import {normalizePluginOptions} from '@docusaurus/utils-validation';
 import collectRedirects from '../collectRedirects';
 import {validateOptions} from '../options';
+import type {DocusaurusConfig} from '@docusaurus/types';
 import type {Options} from '../options';
 import type {PluginContext} from '../types';
 
 function createTestPluginContext(
   options?: Options,
   relativeRoutesPaths: string[] = [],
+  siteConfig: Partial<DocusaurusConfig> = {},
 ): PluginContext {
   return {
     outDir: '/tmp',
     baseUrl: 'https://docusaurus.io',
     relativeRoutesPaths,
     options: validateOptions({validate: normalizePluginOptions, options}),
+    siteConfig: {onDuplicateRoutes: 'warn', ...siteConfig} as DocusaurusConfig,
   };
 }
 
@@ -308,9 +311,10 @@ describe('collectRedirects', () => {
       collectRedirects(
         createTestPluginContext(
           {
-            createRedirects: (routePath) => {
+            // @ts-expect-error: for test
+            createRedirects(routePath) {
               if (routePath === '/') {
-                return [[`/fromPath`]] as unknown as string;
+                return [[`/fromPath`]];
               }
               return undefined;
             },
@@ -356,4 +360,44 @@ describe('collectRedirects', () => {
       },
     ]);
   });
+
+  it('throws when creating duplicate redirect routes and onDuplicateRoutes=throw', () => {
+    expect(() =>
+      collectRedirects(
+        createTestPluginContext(
+          {
+            createRedirects() {
+              return '/random-path';
+            },
+          },
+          ['/path-one', '/path-two'],
+          {onDuplicateRoutes: 'throw'},
+        ),
+        undefined,
+      ),
+    ).toThrowErrorMatchingInlineSnapshot(`
+      "@docusaurus/plugin-client-redirects: multiple redirects are created with the same "from" pathname: "/random-path"
+      It is not possible to redirect the same pathname to multiple destinations:
+      - {"from":"/random-path","to":"/path-one"}
+      - {"from":"/random-path","to":"/path-two"}"
+    `);
+    expect(() =>
+      collectRedirects(
+        createTestPluginContext(
+          {
+            redirects: [
+              {from: '/path-three', to: '/path-one'},
+              {from: '/path-two', to: '/path-one'},
+            ],
+          },
+          ['/path-one', '/path-two'],
+          {onDuplicateRoutes: 'throw'},
+        ),
+        undefined,
+      ),
+    ).toThrowErrorMatchingInlineSnapshot(`
+      "@docusaurus/plugin-client-redirects: some redirects would override existing paths, and will be ignored:
+      - {"from":"/path-two","to":"/path-one"}"
+    `);
+  });
 });

packages/docusaurus-plugin-client-redirects/src/collectRedirects.ts

@@ -102,27 +102,29 @@ function filterUnwantedRedirects(
   Object.entries(_.groupBy(redirects, (redirect) => redirect.from)).forEach(
     ([from, groupedFromRedirects]) => {
       if (groupedFromRedirects.length > 1) {
-        logger.error`name=${'@docusaurus/plugin-client-redirects'}: multiple redirects are created with the same "from" pathname: path=${from}
-It is not possible to redirect the same pathname to multiple destinations: ${groupedFromRedirects.map(
+        logger.report(
+          pluginContext.siteConfig.onDuplicateRoutes,
+        )`name=${'@docusaurus/plugin-client-redirects'}: multiple redirects are created with the same "from" pathname: path=${from}
+It is not possible to redirect the same pathname to multiple destinations:${groupedFromRedirects.map(
           (r) => JSON.stringify(r),
         )}`;
       }
     },
   );
   const collectedRedirects = _.uniqBy(redirects, (redirect) => redirect.from);
 
-  // We don't want to override an already existing route with a redirect file!
-  const redirectsOverridingExistingPath = collectedRedirects.filter(
-    (redirect) => pluginContext.relativeRoutesPaths.includes(redirect.from),
-  );
+  const {false: newRedirects = [], true: redirectsOverridingExistingPath = []} =
+    _.groupBy(collectedRedirects, (redirect) =>
+      pluginContext.relativeRoutesPaths.includes(redirect.from),
+    );
   if (redirectsOverridingExistingPath.length > 0) {
-    logger.error`name=${'@docusaurus/plugin-client-redirects'}: some redirects would override existing paths, and will be ignored: ${redirectsOverridingExistingPath.map(
+    logger.report(
+      pluginContext.siteConfig.onDuplicateRoutes,
+    )`name=${'@docusaurus/plugin-client-redirects'}: some redirects would override existing paths, and will be ignored:${redirectsOverridingExistingPath.map(
       (r) => JSON.stringify(r),
     )}`;
   }
-  return collectedRedirects.filter(
-    (redirect) => !pluginContext.relativeRoutesPaths.includes(redirect.from),
-  );
+  return newRedirects;
 }
 
 function createRedirectsOptionRedirects(

packages/docusaurus-plugin-client-redirects/src/index.ts

@@ -31,6 +31,7 @@ export default function pluginClientRedirectsPages(
         baseUrl: props.baseUrl,
         outDir: props.outDir,
         options,
+        siteConfig: props.siteConfig,
       };
 
       const redirects: RedirectItem[] = collectRedirects(

packages/docusaurus-plugin-client-redirects/src/types.ts

@@ -11,7 +11,7 @@ import type {PluginOptions} from './options';
 /**
  * The minimal infos the plugin needs to work
  */
-export type PluginContext = Pick<Props, 'outDir' | 'baseUrl'> & {
+export type PluginContext = Pick<Props, 'outDir' | 'baseUrl' | 'siteConfig'> & {
   options: PluginOptions;
   relativeRoutesPaths: string[];
 };

website/docs/api/plugins/plugin-client-redirects.md

@@ -50,6 +50,12 @@ Accepted fields:
 </APITable>
 ```
 
+:::note
+
+This plugin will also read the [`siteConfig.onDuplicateRoutes`](../docusaurus.config.js.md#onDuplicateRoutes) config to adjust its logging level when multiple files will be emitted to the same location.
+
+:::
+
 ### Types {#types}
 
 #### `RedirectRule` {#RedirectRule}