[Sema] Warn about redundant ': Any' conformances #17242
Closed
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
- Protocol decls don't have explicit generic parameters, so don't use their location. - Get the location of the extended type token rather than the end brace token. Neither of these paths are being exercised yet, so no tests to accompany.
Such a stated conformance is always redundant. This patch purposefully ignores conformance constraints that are parsed as inheritance clauses, such as with protocols and generic placeholders (e.g '<T : Any>'). These are best diagnosed in the generic signature builder.
hamishknight
force-pushed
the
warn-conform-any
branch
from
41b493b to
f4691c0
Compare
hamishknight
commented
Jun 17, 2018
| "redundant conformance of %0 to %1", (Type, Type)) | ||
| NOTE(all_types_implicitly_conform_to,none, | ||
| "all types implicitly conform to %0", (Type)) | ||
|
|
There was a problem hiding this comment.
An alternative phrasing for the note would be "all types are subtypes of %0", which is more technically correct for Any as it's not actually a protocol you can conform to (just an empty protocol composition) – but I feel the current wording is more user friendly. Thoughts?
|
Superseded by #17425 |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This is the first half of the implementation to warn about
: Anyconformances and constraints (I decided to split it up as the implementation for the removal fix-its for constraints in the generic signature builder is proving to be more involved than I thought it would).In this PR is the logic that deals with conformances. Note that we avoid dealing with protocols and generic placeholders in the added logic, as that will be covered by a follow-up PR that diagnoses redundant
: Anyconstraints in the generic signature builder (andcheckInheritanceClausecan get called more than once when dealing with generic signatures, which would incorrectly lead to multiple warnings being emitted in that case).Resolves SR-8008.