Description:
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DateTime::__construct and its alias, date_create function, are returning weird results for the following cases:
1. date_create('test') => returns false, which is expected according to documentation;
2. date_create('a test') => retuns the DateTime object constructed as "new DateTime('now')", which is not expected.

Same is valid for new DateTime() process:
1. new DateTime('test') => throws Exception, which is expected according to documentation;
2. new DateTime('a test') = retuns the DateTime object constructed as "new DateTime('now')", which is not expected.

Test script:
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php -r "var_dump(date_create('test')); // EXPECTED result"

php -r "var_dump(date_create('a test')); // UNEXPECTED result"

Expected result:
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For the script below it should return FALSE also:
php -r "var_dump(date_create('a test')); // UNEXPECTED result"

Actual result:
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For the script below it returns DateTime object constructed as "new DateTime('now')":
php -r "var_dump(date_create('a test')); // UNEXPECTED result"