feat(theme): add versions attribute to docsVersionDropdown navbar item

packages/docusaurus-theme-classic/src/__tests__/options.test.ts

@@ -827,6 +827,110 @@ describe('themeConfig', () => {
       );
     });
   });
+
+  describe('docsVersionDropdown', () => {
+    describe('versions', () => {
+      it('accepts array of strings', () => {
+        const config = {
+          navbar: {
+            items: [
+              {
+                type: 'docsVersionDropdown',
+                versions: ['current', '1.0'],
+              },
+            ],
+          },
+        };
+        testValidateThemeConfig(config);
+      });
+
+      it('rejects empty array of strings', () => {
+        const config = {
+          navbar: {
+            items: [
+              {
+                type: 'docsVersionDropdown',
+                versions: [],
+              },
+            ],
+          },
+        };
+        expect(() =>
+          testValidateThemeConfig(config),
+        ).toThrowErrorMatchingInlineSnapshot(
+          `""navbar.items[0].versions" must contain at least 1 items"`,
+        );
+      });
+
+      it('rejects array of non-strings', () => {
+        const config = {
+          navbar: {
+            items: [
+              {
+                type: 'docsVersionDropdown',
+                versions: [1, 2],
+              },
+            ],
+          },
+        };
+        expect(() =>
+          testValidateThemeConfig(config),
+        ).toThrowErrorMatchingInlineSnapshot(
+          `""navbar.items[0].versions[0]" must be a string"`,
+        );
+      });
+
+      it('accepts dictionary of version objects', () => {
+        const config = {
+          navbar: {
+            items: [
+              {
+                type: 'docsVersionDropdown',
+                versions: {current: {}, '1.0': {label: '1.x'}},
+              },
+            ],
+          },
+        };
+        testValidateThemeConfig(config);
+      });
+
+      it('rejects empty dictionary of objects', () => {
+        const config = {
+          navbar: {
+            items: [
+              {
+                type: 'docsVersionDropdown',
+                versions: {},
+              },
+            ],
+          },
+        };
+        expect(() =>
+          testValidateThemeConfig(config),
+        ).toThrowErrorMatchingInlineSnapshot(
+          `""navbar.items[0].versions" must have at least 1 key"`,
+        );
+      });
+
+      it('rejects dictionary of invalid objects', () => {
+        const config = {
+          navbar: {
+            items: [
+              {
+                type: 'docsVersionDropdown',
+                versions: {current: {}, '1.0': {invalid: '1.x'}},
+              },
+            ],
+          },
+        };
+        expect(() =>
+          testValidateThemeConfig(config),
+        ).toThrowErrorMatchingInlineSnapshot(
+          `""navbar.items[0].versions.1.0.invalid" is not allowed"`,
+        );
+      });
+    });
+  });
 });
 
 describe('validateOptions', () => {

packages/docusaurus-theme-classic/src/options.ts

@@ -7,6 +7,10 @@
 
 import {themes} from 'prism-react-renderer';
 import {Joi, URISchema} from '@docusaurus/utils-validation';
+import type {
+  PropVersionItem,
+  PropVersionItems,
+} from '@theme/NavbarItem/DocsVersionDropdownNavbarItem';
 import type {Options, PluginOptions} from '@docusaurus/theme-classic';
 import type {ThemeConfig} from '@docusaurus/theme-common';
 import type {
@@ -210,6 +214,17 @@ const DocsVersionDropdownNavbarItemSchema = NavbarItemBaseSchema.append({
   dropdownActiveClassDisabled: Joi.boolean(),
   dropdownItemsBefore: Joi.array().items(DropdownSubitemSchema).default([]),
   dropdownItemsAfter: Joi.array().items(DropdownSubitemSchema).default([]),
+  versions: Joi.alternatives().try(
+    Joi.array().items(Joi.string().min(1)).min(1),
+    Joi.object<PropVersionItems>()
+      .pattern(
+        Joi.string().min(1),
+        Joi.object<PropVersionItem>({
+          label: Joi.string().min(1),
+        }),
+      )
+      .min(1),
+  ),
 });
 
 const LocaleDropdownNavbarItemSchema = NavbarItemBaseSchema.append({

packages/docusaurus-theme-classic/src/theme-classic.d.ts

@@ -1257,11 +1257,22 @@ declare module '@theme/NavbarItem/DocsVersionDropdownNavbarItem' {
   import type {Props as DropdownNavbarItemProps} from '@theme/NavbarItem/DropdownNavbarItem';
   import type {LinkLikeNavbarItemProps} from '@theme/NavbarItem';
 
+  type PropVersionItem = {
+    readonly label?: string;
+  };
+
+  type PropVersionItems = {
+    readonly [version: string]: PropVersionItem;
+  };
+
+  type PropVersions = string[] | PropVersionItems;
+
   export interface Props extends DropdownNavbarItemProps {
     readonly docsPluginId?: string;
     readonly dropdownActiveClassDisabled?: boolean;
     readonly dropdownItemsBefore: LinkLikeNavbarItemProps[];
     readonly dropdownItemsAfter: LinkLikeNavbarItemProps[];
+    readonly versions?: PropVersions;
   }
 
   export default function DocsVersionDropdownNavbarItem(

packages/docusaurus-theme-classic/src/theme/NavbarItem/DocsVersionDropdownNavbarItem.tsx

@@ -16,14 +16,68 @@ import {translate} from '@docusaurus/Translate';
 import {useLocation} from '@docusaurus/router';
 import DefaultNavbarItem from '@theme/NavbarItem/DefaultNavbarItem';
 import DropdownNavbarItem from '@theme/NavbarItem/DropdownNavbarItem';
-import type {Props} from '@theme/NavbarItem/DocsVersionDropdownNavbarItem';
+import type {
+  Props,
+  PropVersions,
+  PropVersionItem,
+} from '@theme/NavbarItem/DocsVersionDropdownNavbarItem';
 import type {LinkLikeNavbarItemProps} from '@theme/NavbarItem';
 import type {
   GlobalVersion,
   GlobalDoc,
   ActiveDocContext,
 } from '@docusaurus/plugin-content-docs/client';
 
+type VersionItem = {
+  version: GlobalVersion;
+  label: string;
+};
+
+function getVersionItems(
+  versions: GlobalVersion[],
+  configs?: PropVersions,
+): VersionItem[] {
+  if (configs) {
+    // Collect all the versions we have
+    const versionMap = new Map<string, GlobalVersion>(
+      versions.map((version) => [version.name, version]),
+    );
+
+    const toVersionItem = (
+      name: string,
+      config?: PropVersionItem,
+    ): VersionItem => {
+      const version = versionMap.get(name);
+      if (!version) {
+        throw new Error(`No docs version exist for name '${name}', please verify your 'docsVersionDropdown' navbar item versions config.
+Available version names:\n- ${versions.map((v) => `${v.name}`).join('\n- ')}`);
+      }
+      return {version, label: config?.label ?? version.label};
+    };
+
+    if (Array.isArray(configs)) {
+      return configs.map((name) => toVersionItem(name, undefined));
+    } else {
+      return Object.entries(configs).map(([name, config]) =>
+        toVersionItem(name, config),
+      );
+    }
+  } else {
+    return versions.map((version) => ({version, label: version.label}));
+  }
+}
+
+function useVersionItems({
+  docsPluginId,
+  configs,
+}: {
+  docsPluginId: Props['docsPluginId'];
+  configs: Props['versions'];
+}): VersionItem[] {
+  const versions = useVersions(docsPluginId);
+  return getVersionItems(versions, configs);
+}
+
 function getVersionMainDoc(version: GlobalVersion): GlobalDoc {
   return version.docs.find((doc) => doc.id === version.mainDocId)!;
 }
@@ -40,23 +94,47 @@ function getVersionTargetDoc(
   );
 }
 
+// The version item to use for the "dropdown button"
+function useDisplayedVersionItem({
+  docsPluginId,
+  versionItems,
+}: {
+  docsPluginId: Props['docsPluginId'];
+  versionItems: VersionItem[];
+}): VersionItem {
+  // The order of the candidates matters!
+  const candidates = useDocsVersionCandidates(docsPluginId);
+  const candidateItems = candidates
+    .map((candidate) => versionItems.find((vi) => vi.version === candidate))
+    .filter((vi) => vi !== undefined);
+  return candidateItems[0] ?? versionItems[0]!;
+}
+
 export default function DocsVersionDropdownNavbarItem({
   mobile,
   docsPluginId,
   dropdownActiveClassDisabled,
   dropdownItemsBefore,
   dropdownItemsAfter,
+  versions: configs,
   ...props
 }: Props): ReactNode {
   const {search, hash} = useLocation();
   const activeDocContext = useActiveDocContext(docsPluginId);
-  const versions = useVersions(docsPluginId);
   const {savePreferredVersionName} = useDocsPreferredVersion(docsPluginId);
+  const versionItems = useVersionItems({docsPluginId, configs});
+  const displayedVersionItem = useDisplayedVersionItem({
+    docsPluginId,
+    versionItems,
+  });
 
-  function versionToLink(version: GlobalVersion): LinkLikeNavbarItemProps {
+  function versionItemToLink({
+    version,
+    label,
+  }: VersionItem): LinkLikeNavbarItemProps {
     const targetDoc = getVersionTargetDoc(version, activeDocContext);
     return {
-      label: version.label,
+      label,
       // preserve ?search#hash suffix on version switches
       to: `${targetDoc.path}${search}${hash}`,
       isActive: () => version === activeDocContext.activeVersion,
@@ -66,12 +144,10 @@ export default function DocsVersionDropdownNavbarItem({
 
   const items: LinkLikeNavbarItemProps[] = [
     ...dropdownItemsBefore,
-    ...versions.map(versionToLink),
+    ...versionItems.map(versionItemToLink),
     ...dropdownItemsAfter,
   ];
 
-  const dropdownVersion = useDocsVersionCandidates(docsPluginId)[0];
-
   // Mobile dropdown is handled a bit differently
   const dropdownLabel =
     mobile && items.length > 1
@@ -81,11 +157,13 @@ export default function DocsVersionDropdownNavbarItem({
           description:
             'The label for the navbar versions dropdown on mobile view',
         })
-      : dropdownVersion.label;
+      : displayedVersionItem.label;
+
   const dropdownTo =
     mobile && items.length > 1
       ? undefined
-      : getVersionTargetDoc(dropdownVersion, activeDocContext).path;
+      : getVersionTargetDoc(displayedVersionItem.version, activeDocContext)
+          .path;
 
   // We don't want to render a version dropdown with 0 or 1 item. If we build
   // the site with a single docs version (onlyIncludeVersions: ['1.0.0']),

website/docs/api/themes/theme-configuration.mdx

@@ -597,11 +597,23 @@ Accepted fields:
 | `dropdownItemsAfter` | <code>[LinkLikeItem](#navbar-dropdown)[]</code> | `[]` | Add additional dropdown items at the end of the dropdown. |
 | `docsPluginId` | `string` | `'default'` | The ID of the docs plugin that the doc versioning belongs to. |
 | `dropdownActiveClassDisabled` | `boolean` | `false` | Do not add the link active class when browsing docs. |
+| `versions` | `DropdownVersions` | `undefined` | Specify a custom list of versions to include in the dropdown. See [the versioning guide](../../guides/docs/versioning.mdx#docsVersionDropdown) for details. |
 
 ```mdx-code-block
 </APITable>
 ```
 
+Types:
+
+```ts
+type DropdownVersion = {
+  /** Allows you to provide a custom display label for each version. */
+  label?: string;
+};
+
+type DropdownVersions = string[] | {[versionName: string]: DropdownVersion};
+```
+
 Example configuration:
 
 ```js title="docusaurus.config.js"

website/docs/guides/docs/versioning.mdx

@@ -258,7 +258,7 @@ See [docs plugin configuration](../../api/plugins/plugin-content-docs.mdx#config
 
 ## Navbar items {#navbar-items}
 
-We offer several navbar items to help you quickly set up navigation without worrying about versioned routes.
+We offer several docs navbar items to help you quickly set up navigation without worrying about versioned routes.
 
 - [`doc`](../../api/themes/theme-configuration.mdx#navbar-doc-link): a link to a doc.
 - [`docSidebar`](../../api/themes/theme-configuration.mdx#navbar-doc-sidebar): a link to the first item in a sidebar.
@@ -271,6 +271,52 @@ These links would all look for an appropriate version to link to, in the followi
 2. **Preferred version**: the version that the user last viewed. If there's no history, fall back to...
 3. **Latest version**: the default version that we navigate to, configured by the `lastVersion` option.
 
+## `docsVersionDropdown` {#docsVersionDropdown}
+
+By default, the [`docsVersionDropdown`](../../api/themes/theme-configuration.mdx#navbar-docs-version-dropdown) displays a dropdown with all the available docs versions.
+
+The `versions` attribute allows you to display a subset of the available docs versions in a given order:
+
+```js title="docusaurus.config.js"
+export default {
+  themeConfig: {
+    navbar: {
+      items: [
+        {
+          type: 'docsVersionDropdown',
+          // highlight-start
+          versions: ['current', '3.0', '2.0'],
+          // highlight-end
+        },
+      ],
+    },
+  },
+};
+```
+
+Passing a `versions` object, lets you override the display label of each version:
+
+```js title="docusaurus.config.js"
+export default {
+  themeConfig: {
+    navbar: {
+      items: [
+        {
+          type: 'docsVersionDropdown',
+          // highlight-start
+          versions: {
+            current: {label: 'Version 4.0'},
+            '3.0': {label: 'Version 3.0'},
+            '2.0': {label: 'Version 2.0'},
+          },
+          // highlight-end
+        },
+      ],
+    },
+  },
+};
+```
+
 ## Recommended practices {#recommended-practices}
 
 ### Version your documentation only when needed {#version-your-documentation-only-when-needed}