Description:
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If $needle is a string that ends with a newline, strpos() does not find the string in the $haystack, although it is there.

Reproduce code:
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$text = <<<TEXT
This is just some text, with 

something in the middle

that has newlines around it.
TEXT;

// The text contains both needles below:

$result = strpos($text, "\nsomething in the middle");
echo 'This works: '; var_dump($result);

echo "\n<br>\n";

$buggy_result = strpos($text, "something in the middle\n");
echo 'This does not: '; var_dump($buggy_result);

Expected result:
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I expect matching for both "\nsomething in the middle" and "something in the middle\n" to return an integer. Matching for "something in the middle", without the newline, returns int(33) (as expected).


Actual result:
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I get boolean false when matching for a string with "\n" at the end of $needle:

This works: int(32) 
This does not: bool(false)