Eliminate usage of Zend_Exception from Magento 2 Open Source

[vkublytskyi]

References count: 4
Used in EE/B2B: yes

Acceptance Criteria:

1. Usage of Zend_Exception removed from Magento 2 Open Source
   • all references to Zend_Exception are removed from Magento 2 Open Source
   • added static a test that verifies that Zend_Exception is not used
   • Travis builds are green on PHP 7.1 environment
   • all backward incompatible changes are documented (if any)
   • if possible ZF1 component replaced by embedded PHP functionality or PSR interface otherwise migrated to ZF2
   • if ZF1 component replaced by ZF2 component:
     • there is an explanation why it is required to use external dependency
     • if usage of old ZF1 component was exposed in M2 interface/class signatures it is removed for new code
     • there is a list of PHP 7.2 compatibility issues of new ZF2 component
       OR
2. There is an explanation why it is impossible to delete this dependency now:
   • described scope of work that is necessary to totally remove usage of Zend_Exception
   • described what backward incompatible changes will be caused by dependency removal
   • listed what other ZF1 components are required for Zend_Exception to support M2
     (if only limited functionality of Zend_Exception is used by M2
     then not all dependencies may be required and some part of Zend_Exception
     still may be removed if has incompatibility with PHP 7.2)
   • listed PHP 7.2 compatibility issues for Zend_Exception

[dcabrejas]

@vkublytskyi Hey, I searched the project for Zend_Exception class and couldn't find any references to that class outside of the zendframework1 package. Has this issue already been resolved? I was on the 2.3-develop branch.

[vkublytskyi]

@dcabrejas seems there is still left the last one at https://github.com/magento/magento2/blob/2.3-develop/dev/tests/functional/lib/Magento/Mtf/Util/Generate/Fixture/FieldsProvider.php#L192

[mhauri]

@vkublytskyi can you close this Issue as the elimination of Zend_Exception was done by merging my PR on April 10th. See https://github.com/magento-engcom/php-7.2-support/blob/2.3.1-develop/dev/tests/functional/lib/Magento/Mtf/Util/Generate/Fixture/FieldsProvider.php