docs: add tabbed terminal component, show npm/bun install

src/components/MDX/MDXComponents.tsx

@@ -25,6 +25,7 @@ import Diagram from './Diagram';
 import DiagramGroup from './DiagramGroup';
 import SimpleCallout from './SimpleCallout';
 import TerminalBlock from './TerminalBlock';
+import TabTerminalBlock from './TabTerminalBlock';
 import YouWillLearnCard from './YouWillLearnCard';
 import {Challenges, Hint, Solution} from './Challenges';
 import {IconNavArrow} from '../Icon/IconNavArrow';
@@ -521,6 +522,7 @@ export const MDXComponents = {
   SandpackWithHTMLOutput,
   TeamMember,
   TerminalBlock,
+  TabTerminalBlock,
   YouWillLearn,
   YouWillLearnCard,
   Challenges,

src/components/MDX/TabTerminalBlock.tsx

@@ -0,0 +1,245 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ */
+
+import * as React from 'react';
+import {useState, useEffect, useCallback} from 'react';
+import TerminalBlock from './TerminalBlock';
+import {IconTerminal} from '../Icon/IconTerminal';
+
+type TabOption = {
+  label: string;
+  value: string;
+  content: string;
+};
+
+// Define this outside of any conditionals for SSR compatibility
+const STORAGE_KEY = 'react-terminal-tabs';
+
+// Map key for active tab preferences - only used on client
+let activeTabsByKey: Record<string, string> = {};
+let subscribersByKey: Record<string, Set<(tab: string) => void>> = {};
+
+function saveToLocalStorage() {
+  if (typeof window !== 'undefined') {
+    try {
+      localStorage.setItem(STORAGE_KEY, JSON.stringify(activeTabsByKey));
+    } catch (e) {
+      // Ignore errors
+    }
+  }
+}
+
+function getSubscribers(key: string): Set<(tab: string) => void> {
+  if (!subscribersByKey[key]) {
+    subscribersByKey[key] = new Set();
+  }
+  return subscribersByKey[key];
+}
+
+function setActiveTab(key: string, tab: string) {
+  activeTabsByKey[key] = tab;
+  saveToLocalStorage();
+
+  const subscribers = getSubscribers(key);
+  subscribers.forEach((callback) => callback(tab));
+}
+
+function useTabState(
+  key: string,
+  defaultTab: string
+): [string, (tab: string) => void] {
+  // Start with the default tab for SSR
+  const [activeTab, setLocalActiveTab] = useState(defaultTab);
+  const [initialized, setInitialized] = useState(false);
+
+  // Initialize from localStorage after mount
+  useEffect(() => {
+    // Read from localStorage
+    try {
+      const savedState = localStorage.getItem(STORAGE_KEY);
+      if (savedState) {
+        const parsed = JSON.parse(savedState);
+        if (parsed && typeof parsed === 'object') {
+          Object.assign(activeTabsByKey, parsed);
+        }
+      }
+    } catch (e) {
+      // Ignore errors
+    }
+
+    // Set up storage event listener
+    const handleStorageChange = (e: StorageEvent) => {
+      if (e.key === STORAGE_KEY && e.newValue) {
+        try {
+          const parsed = JSON.parse(e.newValue);
+          if (parsed && typeof parsed === 'object') {
+            Object.assign(activeTabsByKey, parsed);
+
+            Object.entries(parsed).forEach(([k, value]) => {
+              const subscribers = subscribersByKey[k];
+              if (subscribers) {
+                subscribers.forEach((callback) => callback(value as string));
+              }
+            });
+          }
+        } catch (e) {
+          // Ignore errors
+        }
+      }
+    };
+
+    window.addEventListener('storage', handleStorageChange);
+
+    // Now get the value from localStorage or keep using default
+    const storedValue = activeTabsByKey[key] || defaultTab;
+    setLocalActiveTab(storedValue);
+    setInitialized(true);
+
+    // Make sure this key is in our global store
+    if (!activeTabsByKey[key]) {
+      activeTabsByKey[key] = defaultTab;
+      saveToLocalStorage();
+    }
+
+    return () => {
+      window.removeEventListener('storage', handleStorageChange);
+    };
+  }, [key, defaultTab]);
+
+  // Set up subscription effect
+  useEffect(() => {
+    // Skip if not yet initialized
+    if (!initialized) return;
+
+    const onTabChange = (newTab: string) => {
+      setLocalActiveTab(newTab);
+    };
+
+    const subscribers = getSubscribers(key);
+    subscribers.add(onTabChange);
+
+    return () => {
+      subscribers.delete(onTabChange);
+
+      if (subscribers.size === 0) {
+        delete subscribersByKey[key];
+      }
+    };
+  }, [key, initialized]);
+
+  // Create a stable setter function
+  const setTab = useCallback(
+    (newTab: string) => {
+      setActiveTab(key, newTab);
+    },
+    [key]
+  );
+
+  return [activeTab, setTab];
+}
+
+interface TabTerminalBlockProps {
+  /** Terminal's message level: info, warning, or error */
+  level?: 'info' | 'warning' | 'error';
+
+  /**
+   * Tab options, each with a label, value, and content.
+   * Example: [
+   *   { label: 'npm', value: 'npm', content: 'npm install react' },
+   *   { label: 'Bun', value: 'bun', content: 'bun install react' }
+   * ]
+   */
+  tabs?: Array<TabOption>;
+
+  /** Optional initial active tab value */
+  defaultTab?: string;
+
+  /**
+   * Optional storage key for tab state.
+   * All TabTerminalBlocks with the same key will share tab selection.
+   */
+  storageKey?: string;
+}
+
+/**
+ * TabTerminalBlock displays a terminal block with tabs.
+ * Tabs sync across instances with the same storageKey.
+ *
+ * @example
+ * <TabTerminalBlock
+ *   tabs={[
+ *     { label: 'npm', value: 'npm', content: 'npm install react' },
+ *     { label: 'Bun', value: 'bun', content: 'bun install react' }
+ *   ]}
+ * />
+ */
+function TabTerminalBlock({
+  level = 'info',
+  tabs = [],
+  defaultTab,
+  storageKey = 'package-manager',
+}: TabTerminalBlockProps) {
+  // Create a fallback tab if none provided
+  const safeTabsList =
+    tabs && tabs.length > 0
+      ? tabs
+      : [{label: 'Terminal', value: 'default', content: 'No content provided'}];
+
+  // Always use the first tab as initial defaultTab for SSR consistency
+  // This ensures server and client render the same content initially
+  const initialDefaultTab = defaultTab || safeTabsList[0].value;
+
+  // Set up tab state
+  const [activeTab, setTabValue] = useTabState(storageKey, initialDefaultTab);
+
+  const handleTabClick = useCallback(
+    (tabValue: string) => {
+      return () => setTabValue(tabValue);
+    },
+    [setTabValue]
+  );
+
+  // Handle the case with no content - after hooks have been called
+  if (
+    safeTabsList.length === 0 ||
+    safeTabsList[0].content === 'No content provided'
+  ) {
+    return (
+      <TerminalBlock level="error">
+        Error: No tab content provided
+      </TerminalBlock>
+    );
+  }
+
+  const activeTabOption =
+    safeTabsList.find((tab) => tab.value === activeTab) || safeTabsList[0];
+
+  const customHeader = (
+    <div className="flex items-center">
+      <IconTerminal className="mr-3" />
+      <div className="flex items-center">
+        {safeTabsList.map((tab) => (
+          <button
+            key={tab.value}
+            className={`text-sm font-medium px-3 py-1 h-7 mx-0.5 inline-flex items-center justify-center rounded-sm transition-colors ${
+              activeTab === tab.value
+                ? 'bg-gray-50/50 text-primary dark:bg-gray-800/30 dark:text-primary-dark'
+                : 'text-primary dark:text-primary-dark hover:bg-gray-50/30 dark:hover:bg-gray-800/20'
+            }`}
+            onClick={handleTabClick(tab.value)}>
+            {tab.label}
+          </button>
+        ))}
+      </div>
+    </div>
+  );
+
+  return (
+    <TerminalBlock level={level} customHeader={customHeader}>
+      {activeTabOption.content}
+    </TerminalBlock>
+  );
+}
+
+export default TabTerminalBlock;

src/components/MDX/TerminalBlock.tsx

@@ -12,6 +12,7 @@ type LogLevel = 'info' | 'warning' | 'error';
 interface TerminalBlockProps {
   level?: LogLevel;
   children: React.ReactNode;
+  customHeader?: React.ReactNode;
 }
 
 function LevelText({type}: {type: LogLevel}) {
@@ -25,7 +26,11 @@ function LevelText({type}: {type: LogLevel}) {
   }
 }
 
-function TerminalBlock({level = 'info', children}: TerminalBlockProps) {
+function TerminalBlock({
+  level = 'info',
+  children,
+  customHeader,
+}: TerminalBlockProps) {
   let message: string | undefined;
   if (typeof children === 'string') {
     message = children;
@@ -53,15 +58,20 @@ function TerminalBlock({level = 'info', children}: TerminalBlockProps) {
   }, [copied]);
 
   return (
-    <div className="rounded-lg bg-secondary dark:bg-gray-50 h-full">
+    <div className="rounded-lg bg-secondary dark:bg-gray-50 h-full my-4">
       <div className="bg-gray-90 dark:bg-gray-60 w-full rounded-t-lg">
         <div className="text-primary-dark dark:text-primary-dark flex text-sm px-4 py-0.5 relative justify-between">
           <div>
-            <IconTerminal className="inline-flex me-2 self-center" /> Terminal
+            {customHeader || (
+              <>
+                <IconTerminal className="inline-flex me-2 self-center" />{' '}
+                Terminal
+              </>
+            )}
           </div>
           <div>
             <button
-              className="w-full text-start text-primary-dark dark:text-primary-dark "
+              className="w-full text-start text-primary-dark dark:text-primary-dark"
               onClick={() => {
                 window.navigator.clipboard.writeText(message ?? '');
                 setCopied(true);

src/content/blog/2021/12/17/react-conf-2021-recap.md

@@ -43,9 +43,12 @@ In the keynote, we also announced that the React 18 RC is available to try now.
 
 To try the React 18 RC, upgrade your dependencies:
 
-```bash
-npm install react@rc react-dom@rc
-```
+<TabTerminalBlock 
+  tabs={[
+    { label: 'npm', value: 'npm', content: 'npm install react@rc react-dom@rc' },
+    { label: 'Bun', value: 'bun', content: 'bun add react@rc react-dom@rc' }
+  ]}
+/>
 
 and switch to the new `createRoot` API:
 

src/content/blog/2022/03/08/react-18-upgrade-guide.md

@@ -29,15 +29,13 @@ For React Native users, React 18 will ship in a future version of React Native.
 
 To install the latest version of React:
 
-```bash
-npm install react react-dom
-```
-
-Or if you’re using yarn:
-
-```bash
-yarn add react react-dom
-```
+<TabTerminalBlock 
+  tabs={[
+    { label: 'npm', value: 'npm', content: 'npm install react react-dom' },
+    { label: 'yarn', value: 'yarn', content: 'yarn add react react-dom' },
+    { label: 'Bun', value: 'bun', content: 'bun add react react-dom' }
+  ]}
+/>
 
 ## Updates to Client Rendering APIs {/*updates-to-client-rendering-apis*/}