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Reuse of mode containing "starts: { endWithParent: true }" not possible.

See original GitHub issue

I’m still doing my analysis, but maybe anyone already has an idea, so I write everything down here.

In the new rules for the Handlebars language, I found that reusing some mode-definitions did not work because highlight somehow modifies them in context to its parent mode.

I have created a minimal test-case to reproduce this issue:

let hljs = require('../../build');

describe("bugs", function () {
  describe("modes containing 'endsWithParent'", function () {
    it("should be allowed to be reused", function () {
      hljs.registerLanguage('test-language', function (hljs) {

        const TAG_CONTENTS = {className: 'name', begin: /\w+/, starts: {endsWithParent: true}};

        const PAREN_TAG = {className: 'tag', begin: /\(/, end: /\)/, contains: [TAG_CONTENTS]};
        const SQUARE_BRACKET_TAG = {className: 'tag', begin: /\[/, end: /\]/, contains: [TAG_CONTENTS]};

        return {
          contains: [PAREN_TAG, SQUARE_BRACKET_TAG]
        };
      });

      hljs.highlight('test-language', '(abc 123) [abc 123] (abc 123)').value
        .should.equal(
        '<span class="hljs-tag">(<span class="hljs-name">abc</span> 123)</span> ' +
        '<span class="hljs-tag">[<span class="hljs-name">abc</span> 123]</span> ' +
        '<span class="hljs-tag">(<span class="hljs-name">abc</span> 123)</span>'
      )
    })
  })
})

The expected output (“should.equal” above) is

<span class="hljs-tag">(<span class="hljs-name">abc</span> 123)</span> <span class="hljs-tag">[<span class="hljs-name">abc</span> 123]</span> <span class="hljs-tag">(<span class="hljs-name">abc</span> 123)</span>

but the actual output is

<span class="hljs-tag">(<span class="hljs-name">abc</span> 123)</span> <span class="hljs-tag">[<span class="hljs-name">abc</span> 123] (abc 123)</span>

As you can see, the mode for [abc 123] is not terminated after the closing square bracket, but remains until the end of the string.

Looking at the “compiled” language, I can see that the property SQUARE_BRACKET_TAG.contains[0].starts.terminator_end is /\)/ but it should by /\]/