Fix #1885: Check return value before creating dynamic class.

[davidofferman]

Hello!

• Type: bug fix
• Link to issue: NewInstanceOperator fails to check returned class before initiating object. #1885

In raising this pull request, I confirm the following:

• I have checked that another pull request for this purpose does not exist
• I wrote some tests for this PR
• I updated the CHANGELOG

Small description of change:
Code to check the $classEntry value before calling the method Zephir\BaseBackend::initObject() inside of Zephir\Operators\Other\NewInstanceOperator.

Without this check, it's possible that NULL could be passed through and end up causing a segment fault. Happens when auto-loading a class with a syntax error.

Thanks

[davidofferman]

I'll try to think of a better unit-test so we can pass the travis-ci build. Worst case scenario I can just remove the php extension from the file.

Give me a few days to get around to this unless you have something in mind.
Thanks.

[sergeyklay]

Anyway you can exclude any file/directory from code style testing using https://github.com/phalcon/zephir/blob/development/.php_cs.dist

[davidofferman]

Thanks for that information. I'll keep that in mind for the future.

The latest commit resolves the problem and now passes the automated tests and works as expected.

[sergeyklay]

Thank you