Int div deprecation

[bcardiff]

Depends on #7638.

This PR replaces (hopefully) all usages of Int#/ with Int#//.

Int#/ is marked as deprecated. This will cause some noise while building the compiler and specs since the method is still tested and used in places like macro interpreter. Without turning off warnings on some lexical scope we will need to tolerate that noise for a bit.

Since the stdlib is not ignored bye defualt (only ./lib) if there are some functions without coverage in the stdlib users will notice them and will be able to report :-)

Ref: #2968

---

Submitting as draft until #7638 is merged

[bcardiff]

Ready for the review!

[bew]

What about a more imperative style:

Use Int#// for integer division.

Instead of:

Might need to use Int#// for integer division.

[bcardiff]

Both suggestions addressed.

[j8r]

I have a problem: Int#/ isn't deprecated, it behaves differently.
It's possible to be needlessly spammed for a very valid code, like @RX14 point out.
It should be another type of warning, with a lower priority, disabled by default. information/note maybe.
The deprecated annotation doesn't fit for every API change.

[bcardiff]

@j8r it's disabled by default. When there is a change of the semantic although it's not a formal deprecation you need to call for a review at least. What it is lacking is a way to mark the warning as solved for example in the code. Although I am fine with dealing some false-positive reports.

A fully smooth migration would be to force every / to be either // or temp_float_div and then change temp_float_div to /, but I hardly believe somebody would embrace that journey.

[j8r]

Yes I know warnings are disabled by default @bcardiff. Still, this is misleading to mark Int#/ as deprecated – it's not. This syntax will stay valid, and won't go away (just behave differently).
Deprecated means something that shouldn't be used anymore.

[straight-shoota]

just behave differently

But that's exactly why its current use needs to be deprecated.

You could just see it like this: Int#/(Int) : Int is going to be removed in 0.29.0. If your code uses this method, it shouldn't. That's what the deprecation warning says.
In the same release (probably, except we make the extra detour @bcardiff described 😆 ) we're going to add Int#/(Int) : Float which essentially takes its place. But it's a different method with a different signature and different behaviour. Code using this method might continue to build or might fail, depending how the return value is used.

[j8r]

The signature change, right. I doubt this really matter anyway. This isn't like this warnings will impact non insiders, unless they are curious about tryings flags or read the changelog. That's fine then.