* [TypeCheckConstraints] Adjusting cases where checked casts that cannot be determined statically were producing misleading warnings
* [tests] Adding regression tests for SR-13088
* [TypeCheckConstraints] Adjusting comment and adding an extra test case for SR13035
* [TypeCheckConstraints] Fixing typos in comments
* [AST] Moving implementation of isCollection from ConstraintSystem to AST TypeBase
* [TypeCheckConstraints] Adjusting logic to verify specific conformance to stdlib collection type before emit an downcast warning
* [TypeCheckConstraints] Creating new CheckedCastContextKind::CollectionElement to be able to verify special cases within typeCheckCheckedCast for collection elements
* [TypeCheckConstraints] Adjusting logic around generic substitution to check both subtype and supertype
* [Sema] Adding isKnownStdlibCollectionType and replacing all usages contraint system method
* [TypeChecker] Reverting fixes around array element types
* [TypeChecker] Abstract logic of check for conditional requirements on TypeChecker::couldDynamicallyConformToProtocol
* [TypeChecker] Ajdustinc can conformDynamically conform and adjust review comments
* [TypeChecker] Ajusting comments and fixing typos
* [TypeChecker] Adjusting existential and archetype logic to check inside couldDynamicConform
* [TypeChecker] Adjusting minor and adding existential check into couldDynamically conform.
* [TypeChecker] Adjusting comments
If the problem is related to an operator and argument is an enum
with associated values mention that conformances to `Equatable`
and `Comparable` are not synthesized in such cases.
Currently it's possible to have a type conflict between different
requirements deduced as the same type which leads to incorrect
diagnostics. To mitigate that let's adjust how "fixed" requirements
are stored - instead of using resolved type for the left-hand side,
let's use originating generic parameter type.
Instead of special casing argument-to-parameter matching for
object literal expressions, let's allow constraint system to
lookup a witness initializer and apply it to the given set
of arguments.
This also simplifies constraint application because
`coerceCallArguments` could be used to form type-checked
argument expression.
If aggregate fix (based on callee locator) differs only in picked
overload choices, let's diagnose that via `diagnoseForAmbiguity`
associated with a particular fix kind all solutions share, that
would produce a tailored diagnostic instead of the most general one.
Refactor `diagnoseAmbiguityWithFixes` as follows:
- Aggregate all of the available fixes based on callee locator;
- For each ambiguous overload match aggregated fixes and diagnose;
- Discard all of the fixes which have been already considered
as part of overload diagnostics;
- Diagnose remaining (uniqued based on kind + locator) fixes
iff they appear in all of the solutions.
- `getCalleeLocator`, if given locator ends at `ArgumentAttribute`
strip the last element which makes sure that produced locator
always refers directly to argument-to-parameter conversion.
- `simplifyLocator`, always leave `ArgumentAttribute` in the path
because it's useful for diagnostics.
