Searching for a user or group is case-sensitive

[ScharfViktor]

ocis local v.1.20

• start ocis with idm (https://owncloud.dev/extensions/idm/setup/)
• create new user "marie" (displayName and onPremisesSamAccountName- low case)
• create new group "new group" (displayName is low case)
• try to share file to "Marie" or "New group"

Expected: Marie and the New Group are found in the sharing dialog

Actual: user or group not found.
and reverse: If we create a user or group in upper case, we cannot find them in lower case.

[phil-davis]

Note: in oC10 groups are case-sensitive. "Finance" and "finance" are two different groups. But when starting to share with "Fina" or "fina" both groups "Finance" and "finance" are shown as possibilities in the classic webUI and by the API that returns the potential matches.

In oC10 users are not case-sensitive - "Marie" and "marie" are the same user.

[rhafer]

This seems to be a bug in the substring filtering code in libregraph/idm. It only seems to happen in when using substring search, like e.g when trying to share with users/groups. (Still need to take a deeper look into that)

Regarding the case-sensitivness: As we're currently backed by an LDAP server by default in oCIS, user- and groupnames are both case-insensitive. It should not even be possible to create the groups Finance and finance at the same time. (If it is, that would be another bug in libregraph/idm)

[rhafer]

Duplicate of #547