[SR-14232] Documentation comments from witnessed protocol requirement favoured over own documentation

[karwa]

Previous ID	SR-14232
Radar	None
Original Reporter	@karwa
Type	Bug

Attachment: Download

Environment

Xcode Version 12.4 (12D4e)

Apple Swift version 5.3.2 (swiftlang-1200.0.45 clang-1200.0.32.28).

Additional Detail from JIRA

Votes	0
Component/s	CodeCompletion
Labels	Bug
Assignee	None
Priority	Medium

md5: 44c973aa5bca6206d65f65cd774f99aa

Issue Description:

When an initializer witnesses a protocol requirement, documentation from the protocol will be favoured over the witness' own documentation. This is unfortunate - for example, I'm making a type which conforms to LosslessStringConvertible, and I'd like to document on the initializer which formats the type is able to parse, but this gets lost and it just shows generic LSC documentation about instantiating a type from a string.

struct Foo: LosslessStringConvertible {
  
  /// My documentation comment.
  ///
  /// Hello, world!
  ///
  init?<S>(_ description: S) where S: StringProtocol {}
  var description: String { "" }
}


func testDocComment() {
  Foo(                     // <- Autocomplete here, after the '('
}

See the documentation summary in the autocomplete window of the attached screenshot.