Since the rule is to prioritize names over types, let's diagnose
ambiguous solutions containing subscript operator fix as missing
member and list possible candidates to use.
Fix to use subscript operator instead of spelled out name helps
to produce a solution, that makes it much easier to diagnose
problems precisely and provide proper fix-its, it also helps to
diagnose ambiguous cases, and stacks up nicely with other errors.
Detect and fix situations when (force) unwrap is used on
a non-optional type, this helps to diagnose invalid unwraps
precisely and provide fix-its.
Resolves: [SR-8977](https://bugs.swift.org/browse/SR-8977)
Resolves: rdar://problem/45218255
Fuzzing found a problem related to re-typecheck introducing
`MemeberRefExpr` into AST with failing requirements which
are then diagnosted via fixes, quite unlikely case to be
found in the wild.
Suggest to add `()` (form a call) to correctly forward argument function
originated from `@autoclosure` parameter to function parameter itself
marked as `@autoclosure`.
* Gardening for `@dynamicMemberLookup`.
- Unify code style of `@dynamicMemberLookup` and `@dynamicCallable` implementations.
- Use consistent variable names, diagnostic messages, doc comments, etc.
- Move `@dynamicMemberLookup` test to `test/attr` directory.
Let's keep track of type mismatch between type deduced
for the body of the closure vs. what is requested
contextually, it makes it much easier to diagnose
problems like:
```swift
func foo(_: () -> Int) {}
foo { "hello" }
```
Because we can pin-point problematic area of the source
when the rest of the system is consistent.
Resolves: rdar://problem/40537960
Since 'try?' no longer unconditionally adds a layer of optional, converting it
to 'try!' will no longer unconditionally remove a layer of optional. So let's not
suggest it. This leads to better diagnostics anyway.
There's no need to instantiate archetypes in the generic environment
of the declaration being opened.
A couple of diagnostics changed. They were already misleading, and the
new diagnostics, while different, are not any more misleading than
before.
This silences the instances of the warning from Visual Studio about not all
codepaths returning a value. This makes the output more readable and less
likely to lose useful warnings. NFC.
Merge logic from `diagnoseAssignmentFailure` and `diagnoseSubElementFailure`
into new `AssignmentFailure`, together with their support functions, which
decouples `CSDiagnostics` from `CSDiag` and scrubs latter from some functionality.
If all of the solutions in the set have a single fix, which points
to the common anchor, attempt to diagnose the failure as an
ambiguity with a list of candidates and their related problems as notes.
Having richer message like that helps to understand why something is
ambiguous e.g. if there are two overloads, one requires conformance
to some protocol and another has a same-type requirement on some type,
but neither matched exactly, having both candidates in the diagnostic
message with associated errors, instead of simplify pointing to related
declarations, helps tremendously.
The flag is used to indicate that caller is interested in
diagnostic to be a note instead of an error, it's useful
when trying to diagnose ambiguities.
- getAsDeclOrDeclExtensionContext -> getAsDecl
This is basically the same as a dyn_cast, so it should use a 'getAs'
name like TypeBase does.
- getAsNominalTypeOrNominalTypeExtensionContext -> getSelfNominalTypeDecl
- getAsClassOrClassExtensionContext -> getSelfClassDecl
- getAsEnumOrEnumExtensionContext -> getSelfEnumDecl
- getAsStructOrStructExtensionContext -> getSelfStructDecl
- getAsProtocolOrProtocolExtensionContext -> getSelfProtocolDecl
- getAsTypeOrTypeExtensionContext -> getSelfTypeDecl (private)
These do /not/ return some form of 'this'; instead, they get the
extended types when 'this' is an extension. They started off life with
'is' names, which makes sense, but changed to this at some point. The
names I went with match up with getSelfInterfaceType and
getSelfTypeInContext, even though strictly speaking they're closer to
what getDeclaredInterfaceType does. But it didn't seem right to claim
that an extension "declares" the ClassDecl here.
- getAsProtocolExtensionContext -> getExtendedProtocolDecl
Like the above, this didn't return the ExtensionDecl; it returned its
extended type.
This entire commit is a mechanical change: find-and-replace, followed
by manual reformatted but no code changes.
This is going to make adding same-type and superclass requirement
failures might easier, because they only have to supply custom
diagnostic messages and substituted types.
Change logic to traverse the chain of declaration contexts
starting for "affected" declaration's parent and check if the
requirement is satisfied by one of them, if so return it as
requirement's declaration context.
Extract this logic into a method on `RequirementFailure` to make
it accessible for other types of requirement failure diagnostics.
