fix ifinite loop caused by php brace matcher in embedded lexer context

[haidubogdan]

This pull request tries to fix issue #7803 .

Php brace matcher used for highlighting (if, foreach ) statements like <?php if ($x): ?> ...<?php endif;?> loops through tokens until it finds the opening parenthesis.
The current implementation can trigger a infinite loop for a embedded usage of Php lexer as there is no exit mechanism beside the PhpTokenId.TOKEN check.

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[tmysik]

Please, add a unit test for it, if possible, thank you.

[haidubogdan]

Hmm ... I will see, this would imply a mock mime type for which the coloring lexer will use an embedded php token id.

[tmysik]

Approved, thank you.

[matthiasblaesing]

@haidubogdan It would be helpful to see an example that causes a loop. While I agree, that a test would be the best case, I think a review can substitute that. Infinite loops are really ugly to test for (at least the failing variant).

[haidubogdan]

@matthiasblaesing
Sure, a mock module with php embedding would be enough?
I didn't work with functional test netbeans yet. But I can check some triggers action on a thread for brace matcher.

[matthiasblaesing]

@haidubogdan I'd like to "see" the problem, so instructions how to reproduce (if necessary with code) would be great.

[haidubogdan]

@matthiasblaesing, @tmysik

I've created this branch master...haidubogdan:netbeans:t_php_bracematcher_infinite_loop_test

It's just for simulating the infinite loop.

Context:

I have a custom language support (text/x-php-test).
I include embedding on the lexer site for some tokens using PHPTokenId.languageInPHP() interpolated in {{ }}
The snippet code is :{{(TestClass^:)}} .
I've put dump of a counter in PHPBracesMatcher on line 119
Doing the test for the class EmbeddedBraceMatchingTest will output the infinite counter progress.