[SR-11295] There should be a warning for unnecessary casts

[swift-ci]

Previous ID	SR-11295
Radar	None
Original Reporter	cukier (JIRA User)
Type	Improvement

Additional Detail from JIRA

Votes	0
Component/s	Compiler
Labels	Improvement, StarterBug
Assignee	None
Priority	Medium

md5: 134fdcf76ae60512bbc5e443ad8390d7

Issue Description:

Swift should warn you if you're performing a cast to a type that the thing is already

        let a = "Hello"
        _ = a as String

I would expect something like "casting expression to `String` doesn't change the type" with a fixit of removing "as String"

[harlanhaskins]

This sounds like a good starter bug!

[LucianoPAlmeida]

I can give it a try @harlanhaskins

[LucianoPAlmeida]

@harlanhaskins Here's the PR #26710 🙂

[swift-ci]

Comment by Sidramappa Halake (JIRA)

Unnecessary casting, there should be warning

[MartinP7r]

Hi everyone.

This Issues's status is still `open` although the PR has been merged over a year ago.

#27880

Can we close it? Sorry if I'm missing the point or anything, but navigating things here is still very confusing.

I'm searching through the Starterbugs in order to find something easy to start contributing on. If someone has a suggestion for a beginner, I'd really appreciate it!

[LucianoPAlmeida]

The merge was reverted because of a case we have not handled and we hit a behavior that needs to get right on the compiler in order for us to be able to correctly implement this. Long history short we need a way to track down from where(the source) of an inferred type is coming from. You can see more details on the re-apply PR #27895 As far as stater bug you can checkout this link and check for any unassigned 🙂

[MartinP7r]

Thank you! �