Bugfix - Prevent PHP Warning for count on null on LDAP

[lippl]

When initializing the $pwdGraceUseTimeCount it is not checked if the $pwdGraceUseTime may be null, when pwdgraceusetime attribute my be not defined in LDAP. Starting PHP 7.2 count throws a warning when called on null.
[PHP 7.2] count(): Parameter must be an array or an object that implements Countable
As the ldap search also only returns arrays, [] is used instead of null.
The redundant check for the variable in the if query is also removed, as only arryas, which implement countable, can be passed.
Additionally this is harmonized for all other LDAP attributes querried within the handlePasswordExpiry function.

[georgehrke]

@lippl Is this related to any existing issue?

[georgehrke]

@lippl Can you please add unit tests for it? Thx!

[blizzz]

@lippl looks good from my point of view, just perhaps you can stash the commits into one?

[nickvergessen]

If you only count to see you have more than 0 items, use !empty()

[lippl]

@lippl Is this related to any existing issue?

I have not found any open issue for this yet but rather decided to go straight for a fix

If you only count to see you have more than 0 items, use !empty()

@nickvergessen Thanks for the hint! I applied your suggested changes and also extended this to the initial count($pwdGraceUseTime) for a variable by removing the variable, checking for !empty first and only later in case it is true use the count(), as this should be rare cases.
As you already started some pretty printing I also removed some unnecessary blank spaces as well.

@lippl looks good from my point of view, just perhaps you can stash the commits into one?

If that is all fine with you, I would squash everything into one commit.

[blizzz]

If that is all fine with you, I would squash everything into one commit.

fine with me :)

[blizzz]

Thanks @lippl

[welcome]

Thanks for your first pull request and welcome to the community! Feel free to keep them coming! If you are looking for issues to tackle then have a look at this selection: https://github.com/nextcloud/server/issues?q=is%3Aopen+is%3Aissue+label%3A%22good+first+issue%22

[blizzz]

/backport to stable18

[blizzz]

/backport to stable17

[blizzz]

/backport to stable16

[backportbot-nextcloud]

backport to stable18 in #20175

[backportbot-nextcloud]

backport to stable17 in #20176

[backportbot-nextcloud]

backport to stable16 in #20177