Fix crash on unfinished HTML in raw

Closes remarkjs/react-markdown#833.

Author: wooorm

lib/index.js

@@ -197,6 +197,15 @@ function element(node, state) {
  *   Nothing.
  */
 function text(node, state) {
+  // Allow `DATA` through `PLAINTEXT`,
+  // but when hanging in a tag for example,
+  // switch back to `DATA`.
+  // Note: `State` is not exposed by `parse5`, so these numbers are fragile.
+  // See: <https://github.com/inikulin/parse5/blob/46cba43/packages/parse5/lib/tokenizer/index.ts#L58>
+  if (state.parser.tokenizer.state > 4) {
+    state.parser.tokenizer.state = 0
+  }
+
   /** @type {CharacterToken} */
   const token = {
     type: Token.TokenType.CHARACTER,

test.js

@@ -409,6 +409,39 @@ test('raw', async function (t) {
     }
   )
 
+  await t.test('should switch to data state at a text node', async function () {
+    assert.deepEqual(
+      raw({
+        type: 'root',
+        children: [
+          {type: 'raw', value: '<details>\n<summary>Complete logs</summary'},
+          {type: 'text', value: '\n'},
+          {type: 'raw', value: '</details>'}
+        ]
+      }),
+      {
+        type: 'root',
+        data: {quirksMode: false},
+        children: [
+          {
+            type: 'element',
+            tagName: 'details',
+            properties: {},
+            children: [
+              {type: 'text', value: '\n'},
+              {
+                type: 'element',
+                tagName: 'summary',
+                properties: {},
+                children: [{type: 'text', value: 'Complete logs\n'}]
+              }
+            ]
+          }
+        ]
+      }
+    )
+  })
+
   await t.test(
     'should support raw nodes (security, unsafe)',
     async function () {