Fix the insertion of multiple domains as wildcard

[rdwebdesign]

What does this PR aim to accomplish?

Fix #3257

When selecting the "Add domain as wildcard" checkbox with multiple domains, only the first one was changed into a wildcard regex.

How does this PR accomplish the above?

Changing kind variable from "exact" to "regex" only after the loop.

The issue happened because the previous code were modifying this variable inside the loop, but after the first domain, the check failed (the kind was wrongly changed before all domains were parsed) and the rest of the domains were not changed into wildcards.

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[rdwebdesign]

Looking at the code, I can see this:

If the user enters *.example.com the domain will be change into a wildcard (line 503) before the *. is removed (line 506, but the domain will never start with "*." after the previous line), resulting in this regex: (\.|^)*\.example\.com.
Is this intended?

The question is: *.example.com should be changed into what regex?

• (\.|^)example\.com$ (every subdomains and also the main domain);
• \.example\.com$ (only subdomains, but not the main domain);
• (\.|^)*\.example\.com$ (same as above, but more complex to parse);

[yubiuser]

Is this intended?

I don't think so. I think the order here is wrong. The removal of *. was meant as a help because users entered domains like this and checked the wildcard box because they think they had to enter *. for it to become a wildcard.

The question is: *.example.com should be changed into what regex?

I think

(.|^)example.com$ (every subdomains and also the main domain);

[rdwebdesign]

Then I will change the order and remove the *. text before turning it into a regex.

[DL6ER]

In v5, it was explicitly the latter: all subdomains but not the domain itself. This is rather uncritical and non-breaking here as the checkbox is just a assistance tool for those inexperienced with regex. To me, *.abc.com does clearly not include abc.com itself, however, this is just me (and Pi-hole v5). You are perfectly right to ask "what would the user expect to happen". I don't know TBH. But @yubiuser may be right (include also the domain itself).

[rdwebdesign]

We can discuss this a little more before we decide. I don't want to change the previous behavior unless we have a good reason.