Description:
------------
Idk if they are connected but similar bug in sphinx itself (http://sphinxsearch.com/bugs/view.php?id=1662) is still not fixed in "Sphinx 2.1.9-id64-release (rel21-r4761)"


Test script:
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$s = new SphinxClient;
$a = $s->escapeString('&');
assert($a === '\&');
$b = $s->escapeString('<');
assert($a === '\<');

Expected result:
----------------
no errors, zero search results

Actual result:
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when escaped string is passed to search it throws "index search: syntax error, unexpected $end near ''"