Issue #185 : replacing deprecated delete() calls with del()

[ppaulis]

Fixing Issue #185
Since redis extension 5.0.0, Deprecation errors are thrown on every Redis::delete() call.
Replacing the delete() calls with del() calls fixes these messages.

[michalbundyra]

@ppaulis Please see PR I've created to your branch: http://github.com/ppaulis/zend-cache/pull/1
All tests there pass! :)

[tigrantv]

@ppaulis , @webimpress please prepare and push these changes to release

[pimjansen]

@webimpress i dont really think this is an enhancement but a bug which is blocking a lot nowadays?

[Ocramius]

Not a bug: needs to indeed land in a new minor, since we are adding compatibility with a new tool, not fixing a bug here.

[Ocramius]

Would most likely need an addition of "conflicts": {"ext-redis": "<5.0.0"} (or a matching version that has the del() API) in composer.json

[michalbundyra]

As @boesing checked del() is available since 2.1.0 release. Ref:

• https://github.com/phpredis/phpredis/tree/2.0.12#delete
• https://github.com/phpredis/phpredis/blob/2.1.0/README.markdown#del-delete

and the latest version available on PECL is 2.2.3:
https://pecl.php.net/package/redis

There is no need to add any conflict.

[michalbundyra]

Thanks, @ppaulis!