refactor(v2): add @theme-init alias to give access to initial components

packages/docusaurus-theme-classic/src/theme/CodeBlock/index.js

@@ -8,11 +8,10 @@
 import React, {useEffect, useState, useRef} from 'react';
 import classnames from 'classnames';
 import Highlight, {defaultProps} from 'prism-react-renderer';
-import defaultTheme from 'prism-react-renderer/themes/palenight';
 import Clipboard from 'clipboard';
 import rangeParser from 'parse-numeric-range';
 import useDocusaurusContext from '@docusaurus/useDocusaurusContext';
-import useThemeContext from '@theme/hooks/useThemeContext';
+import usePrismTheme from '@theme/hooks/usePrismTheme';
 
 import styles from './styles.module.css';
 
@@ -42,10 +41,7 @@ export default ({children, className: languageClassName, metastring}) => {
   const button = useRef(null);
   let highlightLines = [];
 
-  const {isDarkTheme} = useThemeContext();
-  const lightModeTheme = prism.theme || defaultTheme;
-  const darkModeTheme = prism.darkTheme || lightModeTheme;
-  const prismTheme = isDarkTheme ? darkModeTheme : lightModeTheme;
+  const prismTheme = usePrismTheme();
 
   if (metastring && highlightLinesRangeRegex.test(metastring)) {
     const highlightLinesRange = metastring.match(highlightLinesRangeRegex)[1];

packages/docusaurus-theme-classic/src/theme/hooks/usePrismTheme.js

@@ -0,0 +1,26 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+import defaultTheme from 'prism-react-renderer/themes/palenight';
+import useDocusaurusContext from '@docusaurus/useDocusaurusContext';
+import useThemeContext from '@theme/hooks/useThemeContext';
+
+const usePrismTheme = () => {
+  const {
+    siteConfig: {
+      themeConfig: {prism = {}},
+    },
+  } = useDocusaurusContext();
+  const {isDarkTheme} = useThemeContext();
+  const lightModeTheme = prism.theme || defaultTheme;
+  const darkModeTheme = prism.darkTheme || lightModeTheme;
+  const prismTheme = isDarkTheme ? darkModeTheme : lightModeTheme;
+
+  return prismTheme;
+};
+
+export default usePrismTheme;

packages/docusaurus-theme-live-codeblock/src/theme/CodeBlock/index.js

@@ -5,143 +5,32 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import React, {useEffect, useState, useRef} from 'react';
-import classnames from 'classnames';
-import Highlight, {defaultProps} from 'prism-react-renderer';
-import defaultTheme from 'prism-react-renderer/themes/palenight';
-import Clipboard from 'clipboard';
-import rangeParser from 'parse-numeric-range';
+import React from 'react';
 import useDocusaurusContext from '@docusaurus/useDocusaurusContext';
-import useThemeContext from '@theme/hooks/useThemeContext';
+import usePrismTheme from '@theme/hooks/usePrismTheme';
 import Playground from '@theme/Playground';
-
-import styles from './styles.module.css';
-
-const highlightLinesRangeRegex = /{([\d,-]+)}/;
-
-export default ({
-  children,
-  className: languageClassName,
-  live,
-  metastring,
-  ...props
-}) => {
-  const {
-    siteConfig: {
-      themeConfig: {prism = {}},
-    },
-  } = useDocusaurusContext();
-
-  const [showCopied, setShowCopied] = useState(false);
-  const [mounted, setMounted] = useState(false);
-  // The Prism theme on SSR is always the default theme but the site theme
-  // can be in a different mode. React hydration doesn't update DOM styles
-  // that come from SSR. Hence force a re-render after mounting to apply the
-  // current relevant styles. There will be a flash seen of the original
-  // styles seen using this current approach but that's probably ok. Fixing
-  // the flash will require changing the theming approach and is not worth it
-  // at this point.
-  useEffect(() => {
-    setMounted(true);
-  }, []);
-
-  const target = useRef(null);
-  const button = useRef(null);
-  let highlightLines = [];
-
-  const {isDarkTheme} = useThemeContext();
-  const lightModeTheme = prism.theme || defaultTheme;
-  const darkModeTheme = prism.darkTheme || lightModeTheme;
-  const prismTheme = isDarkTheme ? darkModeTheme : lightModeTheme;
-
-  if (metastring && highlightLinesRangeRegex.test(metastring)) {
-    const highlightLinesRange = metastring.match(highlightLinesRangeRegex)[1];
-    highlightLines = rangeParser.parse(highlightLinesRange).filter(n => n > 0);
-  }
-
-  useEffect(() => {
-    let clipboard;
-
-    if (button.current) {
-      clipboard = new Clipboard(button.current, {
-        target: () => target.current,
-      });
+import CodeBlock from '@theme-init/CodeBlock';
+
+const withLiveEditor = Component => {
+  const WrappedComponent = props => {
+    const {isClient} = useDocusaurusContext();
+    const prismTheme = usePrismTheme();
+
+    if (props.live) {
+      return (
+        <Playground
+          key={isClient}
+          scope={{...React}}
+          theme={prismTheme}
+          {...props}
+        />
+      );
     }
 
-    return () => {
-      if (clipboard) {
-        clipboard.destroy();
-      }
-    };
-  }, [button.current, target.current]);
-
-  if (live) {
-    return (
-      <Playground
-        key={mounted}
-        scope={{...React}}
-        code={children.replace(/\n$/, '')}
-        theme={prismTheme}
-        {...props}
-      />
-    );
-  }
-
-  let language =
-    languageClassName && languageClassName.replace(/language-/, '');
-
-  if (!language && prism.defaultLanguage) {
-    language = prism.defaultLanguage;
-  }
-
-  const handleCopyCode = () => {
-    window.getSelection().empty();
-    setShowCopied(true);
-
-    setTimeout(() => setShowCopied(false), 2000);
+    return <Component {...props} />;
   };
 
-  return (
-    <Highlight
-      {...defaultProps}
-      key={mounted}
-      theme={prismTheme}
-      code={children.replace(/\n$/, '')}
-      language={language}>
-      {({className, style, tokens, getLineProps, getTokenProps}) => (
-        <pre className={classnames(className, styles.codeBlock)}>
-          <button
-            ref={button}
-            type="button"
-            aria-label="Copy code to clipboard"
-            className={styles.copyButton}
-            onClick={handleCopyCode}>
-            {showCopied ? 'Copied' : 'Copy'}
-          </button>
-
-          <div ref={target} className={styles.codeBlockLines} style={style}>
-            {tokens.map((line, i) => {
-              if (line.length === 1 && line[0].content === '') {
-                line[0].content = '\n'; // eslint-disable-line no-param-reassign
-              }
-
-              const lineProps = getLineProps({line, key: i});
-
-              if (highlightLines.includes(i + 1)) {
-                lineProps.className = `${lineProps.className} docusaurus-highlight-code-line`;
-              }
-
-              return (
-                <div key={i} {...lineProps}>
-                  {line.map((token, key) => (
-                    <span key={key} {...getTokenProps({token, key})} />
-                  ))}
-                </div>
-              );
-            })}
-          </div>
-        </pre>
-      )}
-    </Highlight>
-  );
+  return WrappedComponent;
 };
+
+export default withLiveEditor(CodeBlock);

packages/docusaurus-theme-live-codeblock/src/theme/Playground/index.js

@@ -14,7 +14,7 @@ import styles from './styles.module.css';
 function Playground({children, theme, transformCode, ...props}) {
   return (
     <LiveProvider
-      code={children}
+      code={children.replace(/\n$/, '')}
       transformCode={transformCode || (code => `${code};`)}
       theme={theme}
       {...props}>

packages/docusaurus/src/server/themes/__tests__/index.ts

@@ -16,6 +16,7 @@ describe('loadThemeAlias', () => {
 
     const alias = loadThemeAlias([theme1Path, theme2Path]);
     expect(alias).toEqual({
+      '@theme-init/Layout': path.join(theme1Path, 'Layout.js'), // TODO: Write separate test case for this?
       '@theme/Footer': path.join(theme1Path, 'Footer/index.js'),
       '@theme-original/Footer': path.join(theme1Path, 'Footer/index.js'),
       '@theme/Navbar': path.join(theme2Path, 'Navbar.js'),

packages/docusaurus/src/server/themes/index.ts

@@ -17,6 +17,11 @@ export function loadThemeAlias(
   themePaths.forEach(themePath => {
     const themeAliases = themeAlias(themePath);
     Object.keys(themeAliases).forEach(aliasKey => {
+      if (aliasKey in aliases) {
+        const componentName = aliasKey.substring(aliasKey.indexOf('/') + 1);
+        aliases[`@theme-init/${componentName}`] = aliases[aliasKey];
+      }
+
       aliases[aliasKey] = themeAliases[aliasKey];
     });
   });