try different approach to JSX

src/languages/javascript.js

@@ -5,15 +5,9 @@ Category: common, scripting
 Website: https://developer.mozilla.org/en-US/docs/Web/JavaScript
 */
 
+import { JSX_MODE, JSX_LANGUAGE } from "./lib/jsx";
+
 export default function(hljs) {
-  var FRAGMENT = {
-    begin: '<>',
-    end: '</>'
-  };
-  var XML_TAG = {
-    begin: /<[A-Za-z0-9\\._:-]+/,
-    end: /\/[A-Za-z0-9\\._:-]+>|\/>/
-  };
   var IDENT_RE = '[A-Za-z$_][0-9A-Za-z$_]*';
   var KEYWORDS = {
     keyword:
@@ -94,6 +88,15 @@ export default function(hljs) {
     hljs.C_LINE_COMMENT_MODE
   ]);
 
+  const containers = [
+    hljs.APOS_STRING_MODE,
+    hljs.QUOTE_STRING_MODE,
+    TEMPLATE_STRING,
+    hljs.C_BLOCK_COMMENT_MODE,
+    hljs.C_LINE_COMMENT_MODE
+  ];
+  hljs.registerLanguage("_jsx", JSX_LANGUAGE({containers}));
+
   return {
     aliases: ['js', 'jsx', 'mjs', 'cjs'],
     keywords: KEYWORDS,
@@ -198,19 +201,7 @@ export default function(hljs) {
             end: /\s*/,
             skip: true,
           },
-          { // JSX
-            variants: [
-              { begin: FRAGMENT.begin, end: FRAGMENT.end },
-              { begin: XML_TAG.begin, end: XML_TAG.end }
-            ],
-            subLanguage: 'xml',
-            contains: [
-              {
-                begin: XML_TAG.begin, end: XML_TAG.end, skip: true,
-                contains: ['self']
-              }
-            ]
-          },
+          JSX_MODE
         ],
         relevance: 0
       },

src/languages/lib/jsx.js

@@ -0,0 +1,110 @@
+import { inherit } from "../../lib/utils";
+
+const FRAGMENT = {
+  begin: '<>',
+  end: '</>'
+};
+const XML_TAG = {
+  begin: /<[A-Za-z0-9\\._:-]+/,
+  end: /\/[A-Za-z0-9\\._:-]+>|\/>/
+};
+
+export const JSX_MODE = { // JSX
+  variants: [
+    { begin: FRAGMENT.begin, end: FRAGMENT.end },
+    { begin: XML_TAG.begin, end: XML_TAG.end }
+  ],
+  subLanguage: '_jsx',
+  contains: [
+    {
+      begin: XML_TAG.begin, end: XML_TAG.end, skip: true,
+      contains: ['self']
+    }
+  ]
+};
+
+// note: this is not a language grammar itself but when called
+// it returns a function that is the language grammar
+// This could be improved if our registerLanguage API was enhanced
+// to support passing options to grammars.
+export const JSX_LANGUAGE = function({containers}) {
+
+  // containers are any blocks which could prevent an inline JS mode
+  // from ending... inline javascript is denoted with `{ code }`
+  // so an example would be a string: ` { "}" }`  Become the } is
+  // inside the container it should be ignored and not counted as
+  // ending the inline JS snippet
+  //
+  // these are passed in because it makes sense that these would
+  // already be defined by the parent language
+  containers = containers.map((x) =>
+    // we need these to be quiet, and not output
+    inherit(x, {skip: true, className: null})
+  )
+
+  return function (hljs) {
+
+    const XML_IDENT_RE = '[A-Za-z0-9\\._:-]+';
+    const XML_ENTITIES = {
+      className: 'symbol',
+      begin: '&[a-z]+;|&#[0-9]+;|&#x[a-f0-9]+;'
+    };
+    const INLINE_JS = {
+      begin: /{/,
+      end: /}/,
+      // needs to eat strings, regex, comments, etc.
+      contains: [].concat(containers),
+      subLanguage: "javascript"
+    };
+    const TAG_INTERNALS = {
+      endsWithParent: true,
+      illegal: /</,
+      relevance: 0,
+      contains: [
+        hljs.C_LINE_COMMENT_MODE,
+        {
+          className: 'attr',
+          begin: XML_IDENT_RE,
+          relevance: 0
+        },
+        {
+          begin: /=\s*/,
+          relevance: 0,
+          contains: [
+            {
+              className: 'string',
+              endsParent: true,
+              variants: [
+                {begin: /"/, end: /"/, contains: [XML_ENTITIES]},
+                {begin: /'/, end: /'/, contains: [XML_ENTITIES]},
+                {begin: /[^\s"'=<>`]+/}
+              ]
+            }
+          ]
+        }
+      ]
+    };
+    const SIMPLE_TAG = {
+      className: 'tag',
+      begin: '</?', end: '/?>',
+      contains: [
+        {
+          className: 'name', begin: /[^\/><\s]+/, relevance: 0
+        },
+        TAG_INTERNALS
+      ]
+    }
+
+    return {
+      className:"xml",
+      case_insensitive: true,
+      disableAutodetect: true,
+      contains: [
+        SIMPLE_TAG,
+        INLINE_JS
+      ]
+    };
+
+  }
+}
+

test/markup/javascript/jsx.txt

@@ -16,8 +16,13 @@ class App extends Component {
     return (
       <BrowserRouter>
         <div>
+          {/* comment */}
+          { test "}" }
           <Route path="/about" component={About} />
           <Route path="/contact" component={Contact} />
+          <div
+            box="yes" // comment
+          />
         </div>
       </BrowserRouter>
     );