add tests and refactor logic

packages/docusaurus-plugin-content-docs/src/client/__tests__/docsClientUtils.test.ts

@@ -12,6 +12,7 @@ import {
   getActiveDocContext,
   getActiveVersion,
   getDocVersionSuggestions,
+  sortVersionsByPathDepth,
 } from '../docsClientUtils';
 import type {
   GlobalPluginData,
@@ -184,12 +185,71 @@ describe('docsClientUtils', () => {
     expect(getActiveVersion(data, '/docs/someDoc')?.name).toBe('version2');
 
     expect(getActiveVersion(data, '/docs/version1')?.name).toBe('version1');
-    expect(getActiveVersion(data, '/docs/version1')?.name).toBe('version1');
+    expect(getActiveVersion(data, '/docs/version1/')?.name).toBe('version1');
     expect(getActiveVersion(data, '/docs/version1/someDoc')?.name).toBe(
       'version1',
     );
   });
 
+  it('sortVersionsByPathDepth', () => {
+    function createVersion(name: string, path: string, isLast: boolean) {
+      return {
+        name,
+        label: name,
+        path,
+        isLast,
+        docs: [],
+        mainDocId: '???',
+        draftIds: [],
+      };
+    }
+    const test1 = [
+      createVersion('current', '/docs', false),
+      createVersion('version2', '/docs/version2', true),
+      createVersion('version1', '/docs/version1', false),
+    ];
+    const test2 = [
+      createVersion('current', '/docs/', false),
+      createVersion('version2', '/docs/version2/', true),
+      createVersion('version1', '/docs/version1/', false),
+    ];
+
+    // docs only website
+    const test3 = [
+      createVersion('current', '/', false),
+      createVersion('version2', '/version2', true),
+      createVersion('version1', '/version1', false),
+    ];
+
+    // docs only with trailing slash
+    const test4 = [
+      createVersion('current', '/', false),
+      createVersion('version2', '/version2/', true),
+      createVersion('version1', '/version1/', false),
+    ];
+
+    expect(sortVersionsByPathDepth(test1)).toEqual([
+      test1[2], // version1
+      test1[1], // version2
+      test1[0], // current
+    ]);
+    expect(sortVersionsByPathDepth(test2)).toEqual([
+      test2[2], // version1
+      test2[1], // version2
+      test2[0], // current
+    ]);
+    expect(sortVersionsByPathDepth(test3)).toEqual([
+      test3[2], // version1
+      test3[1], // version2
+      test3[0], // current
+    ]);
+    expect(sortVersionsByPathDepth(test4)).toEqual([
+      test4[2], // version1
+      test4[1], // version2
+      test4[0], // current
+    ]);
+  });
+
   it('getActiveDocContext', () => {
     const versionNext: GlobalVersion = {
       name: 'next',

packages/docusaurus-plugin-content-docs/src/client/docsClientUtils.ts

@@ -59,20 +59,37 @@ export function getActivePlugin(
 export const getLatestVersion = (data: GlobalPluginData): GlobalVersion =>
   data.versions.find((version) => version.isLast)!;
 
+export function sortVersionsByPathDepth(
+  versions: GlobalVersion[],
+): GlobalVersion[] {
+  return [...versions].sort((a, b) => {
+    const getDepth = (path: string): number => {
+      if (path === '/') {
+        return 0;
+      }
+      const trimmedPath = path.replace(/^\/|\/$/g, '');
+      return trimmedPath ? trimmedPath.split('/').length : 0;
+    };
+
+    const depthA = getDepth(a.path);
+    const depthB = getDepth(b.path);
+
+    // Sort by depth (descending order)
+    if (depthA !== depthB) {
+      return depthB - depthA;
+    }
+
+    // else sort alphabetically
+    return a.path.localeCompare(b.path);
+  });
+}
+
 export function getActiveVersion(
   data: GlobalPluginData,
   pathname: string,
 ): GlobalVersion | undefined {
-  // Sort versions: non-root paths first (by length, descending), then root path
-  const orderedVersionsMetadata = [...data.versions].sort((a, b) => {
-    if (a.path === `${data.path}/`) {
-      return 1;
-    }
-    if (b.path === `${data.path}/`) {
-      return -1;
-    }
-    return b.path.length - a.path.length;
-  });
+  // Sort paths by depth, deepest first
+  const orderedVersionsMetadata = sortVersionsByPathDepth(data.versions);
 
   return orderedVersionsMetadata.find(
     (version) =>