Merge pull request #15 from ueberdosis/feature/parse-code-blocks

Add language support to Code Block’s parseDOM function

babel.config.js

@@ -3,6 +3,7 @@ module.exports = {
     '@babel/preset-env',
   ],
   plugins: [
+    '@babel/plugin-proposal-nullish-coalescing-operator',
     '@babel/plugin-proposal-optional-chaining',
   ],
 }

docs/src/demos/Extensions/CodeBlock/index.spec.js

@@ -69,6 +69,16 @@ context('/api/extensions/code-block', () => {
     })
   })
 
+  it('should parse the language from a HTML code block', () => {
+    cy.get('.ProseMirror').then(([{ editor }]) => {
+      editor.setContent('<pre><code class="language-css">body { display: none; }</code></pre>')
+
+      cy.get('.ProseMirror')
+        .find('pre>code.language-css')
+        .should('have.length', 1)
+    })
+  })
+
   it('should make a code block for js', () => {
     cy.get('.ProseMirror').then(([{ editor }]) => {
       editor.clearContent()

docs/src/docPages/api/extensions/code-block.md

@@ -17,9 +17,10 @@ yarn add @tiptap/extension-code-block
 ```
 
 ## Settings
-| Option | Type   | Default | Description                                  |
-| ------ | ------ | ------- | -------------------------------------------- |
-| class  | string | –       | Add a custom class to the rendered HTML tag. |
+| Option              | Type   | Default   | Description                                                      |
+| ------------------- | ------ | --------- | ---------------------------------------------------------------- |
+| class               | string | –         | Add a custom class to the rendered HTML tag.                     |
+| languageClassPrefix | string | language- | Adds a prefix to language classes that are applied to code tags. |
 
 ## Commands
 | Command   | Options | Description                   |

package.json

@@ -21,6 +21,7 @@
     "reset": "yarn clean:packages && rm -rf ./**/.cache && rm -rf ./**/node_modules && rm -rf ./yarn.lock && yarn install"
   },
   "devDependencies": {
+    "@babel/plugin-proposal-nullish-coalescing-operator": "^7.10.4",
     "@babel/plugin-proposal-optional-chaining": "^7.11.0",
     "@babel/preset-env": "^7.11.5",
     "@types/prosemirror-commands": "^1.0.3",

packages/extension-code-block/index.ts

@@ -1,6 +1,10 @@
 import { Command, Node } from '@tiptap/core'
 import { textblockTypeInputRule } from 'prosemirror-inputrules'
 
+export interface CodeBlockOptions {
+  languageClassPrefix: string,
+}
+
 export type CodeBlockCommand = () => Command
 
 declare module '@tiptap/core/src/Editor' {
@@ -11,9 +15,12 @@ declare module '@tiptap/core/src/Editor' {
 
 export const inputRegex = /^```(?<language>[a-z]*)? $/
 
-export default new Node()
+export default new Node<CodeBlockOptions>()
   .name('code_block')
-  .schema(() => ({
+  .defaults({
+    languageClassPrefix: 'language-',
+  })
+  .schema(({ options }) => ({
     attrs: {
       language: {
         default: null,
@@ -26,9 +33,25 @@ export default new Node()
     defining: true,
     draggable: false,
     parseDOM: [
-      { tag: 'pre', preserveWhitespace: 'full' },
+      {
+        tag: 'pre',
+        preserveWhitespace: 'full',
+        getAttrs(node) {
+          const classAttribute = (node as Element).firstElementChild?.getAttribute('class')
+
+          if (!classAttribute) {
+            return null
+          }
+
+          const regexLanguageClassPrefix = new RegExp(`^(${options.languageClassPrefix})`)
+
+          return { language: classAttribute.replace(regexLanguageClassPrefix, '') }
+        },
+      },
     ],
-    toDOM: node => ['pre', ['code', { class: node.attrs.language && `language-${node.attrs.language}` }, 0]],
+    toDOM: node => ['pre', ['code', {
+      class: node.attrs.language && options.languageClassPrefix + node.attrs.language,
+    }, 0]],
   }))
   .commands(({ name }) => ({
     codeBlock: attrs => ({ commands }) => {

tsconfig.json

@@ -1,6 +1,6 @@
 {
   "compilerOptions": {
-    "target": "esnext",
+    "target": "es2019",
     "module": "esnext",
     "strict": true,
     "jsx": "preserve",