Relates to KT-8834, we continue reducing differences between old and new
inference. Note that as for `SamConversionPerArgument`, this feature
is enabled in the compiler and not in the IDE to avoid breaking code
for those users that already enabled new inference in the compiler
Bug was introduced in b99efb because of lack of tests.
All code in `AbstractTypeCheckerContextForConstraintSystem.extractTypeVariableForSubtype`
related to IN projection looks suspicious and needs further investigation
There was an inconsistency on creating PSI call and corresponding
descriptor. See variable `catchBlocks` from visitor, it's created
only if PSI elements are not null, but for descriptor parameters
there wasn't such check
#KT-32134 Fixed
#EA-139748 Fixed
If new inference is enabled only for IDE analysis, then this feature
will be disabled to reduce difference between new and old inference,
but if new inference is enabled in the compiler, then this feature
will be enabled too to preserve behavior of new inference for
compilation
#KT-32175 Fixed
#KT-32143 Fixed
#KT-32123 Fixed
#KT-32230 Fixed
Consider call `foo(bar())` where bar() returns some type variable `T`;
We had a contract that call `bar` can be completed without completion
of foo (type variables can be inferred from the current context) if `T`
has at least one proper lower constraint (ProperType <: T).
Indeed, new constraints can be added only as upper ones, so there is
no need to grow constraint system.
Unfortunately, we have Exact annotation that is used on return type of
elvis. Now, consider the following situation:
```
fun foo(a: Any) {}
fun bar(e: T): @Exact T
foo(bar("str"))
```
Here, because of Exact annotation, constraint with `Any`-type will be
added as an equal one => our prerequisite that there will be no new
lower constraints is false. `bar("str")` is inferred to Any in OI,
this seems conceptually wrong, but it's another topic of discussion.
In NI we can't just grow constraint system to use outer call because
of another important use-case:
```
fun <T> generic(i: Inv<T>) {}
fun test(a: Inv<*>?, b: Inv<*>) {
generic(a ?: b)
}
```
Common constraint system for these two calls can't be solved
(fundamentally) for this example, only if (a ?: b) and generic(result)
are computed separately.
So, to mitigate initial issue, we'll grow constraint system only if
there is at least one non-proper constraint.
#KT-31969 Fixed
matching
This commit makes several changes in testdata:
- compiler multiplatform tests now contain newly introduced diagnostics
about AMBIGIOUTS_ACTUALS
- MultiModuleHighlighitng tests now contain proper reports about
ACTUAL_MISSING:
- ACTUAL_MISSING should be indeed reported in them, because those
tests don't contain dependsOn edges, only usual intermodule
dependencies
- This error wasn't reported here because expect/actual diagnostics in
common module used to be reported by PlatformExpectedAnnotator, which
had a bit flawed logic for deremining common-modules: it checked for
presence of implementing modules. In those tests, common module has no
implementing modules, so Annotator was returning silently
Note that such configurations (common module without implementing
modules) are almost impossible in real-life projects
- After removal of PlatformExpectedAnnotator, we use
ExpectedActualDeclarationChecker in common modules, which launches all
checks properly
- some QuickFixMultuModuleTests now contain proper reports about
ACTUAL_MISSING. This change is also connected with
PlatformExpectedAnnotator, but now for different reason:
- QuickFixMultiModuleTest used to check for errors in file by running
'analyzeWithAllCompilerChecks' and inspecting returned BindingTrace.
For common modules, there were no diagnostics about expect/actuals in
that trace, because there were no ExpectedActualDeclarationChecker
(and PlatformExpectedAnnotator was reporting diagnostics in ad hoc
trace).
- Again, now we inject EADC in common modules properly, so we see
those errors in trace and report them in test
This commit doesn't change behaviour of any inference algorithm, it
introduces opportunity to switch constraint system that is used for
overload resolution and fix problematic cases by changing one enum
entry.
Due to fundamental changes, there are cases where a new inference
algorithm reports overload resolution ambiguity errors (#KT-31670,
#KT-31758), which is correct from its point of view. However, this is
a breaking change and to really make it, we should be very confident
and have enough motivation for it, therefore, we don't change behavior
now in order to collect more examples (if there are any). And if we
find a lot of erroneous examples, we'll be able to change the behavior
quite simply
It's enough to have at least one good constraint.
Note that the whole algorithm can be a bit more general:
we could check also Out<T>, In<T> and verify that T has good only
lower constraint or upper constraint, but there are questions for
types like Inv<Out<T>>, where T should have lower and upper constraints
#KT-31514 Fixed
There is added a new service named `SubstitutingScopeProvider`, that
provides factory that creates captured types and approximator for them.
In OI they are the same as before commit, for NI they are empty, because
that approximation interferes with NI algorithm
That service is injected into function descriptors and property descriptors
and used for creating `SubstitutingScope` with correct services
Also there is changed time when we approximate captured types in NI
(after all call checkers)
#KT-25290 Fixed
Mostly, these optimisations are picked from the old inference.
Also, remove exponential complexity for flexible types in approximation,
note that more correct fix for this would be to introduce new types
that corresponds just to platform types to avoid nullability problems,
but due to complexity it will be done later
#KT-31415 Fixed
Also that commit removes usages of builtins inside
effect system and starts refactoring of functor
composition via composition instead of inheritance.
There are some changes in testdata related to inference of recursive
functions with implicit return types.
After this commit they all are marked as unresolved. It happens because
those functions have DeferredType as return type, and computing this
type produces recursive exception, which provides “typechecker
recursive problem” diagnostic.
Before this commit, function call was completed successfully, because
call completer didn’t computed that type, and computation of DeferredType
were triggered only in `DataFlowAnalyzer.checkType`.
Now, effect system tries to compute that type while wrapping KotlinTypes
into ESTypes, and effect system itself is triggered in in call completer,
so, call completion doesn’t finish and function call is marked as unresolved.
#KT-31364
There was a silly bug: equal constraint is actually a lower and an upper
constraint, but we checked only presence of lower constraints.
Test is important as here we have one equal constraint and should
complete inner call `foo<Int>()` without propagating it to `bar` to
avoid using `NoInfer` annotation multiple times
There is an inconsistency between old and new inference for storing
receivers of resolved calls. In new inference, for captured types,
receiver will be changed and to preserve behavior of the old inference,
we use original one during important checks.
This is more a workaround than a solution and should be revisited.
#KT-31356 Fixed
#KT-29948 Fixed
#KT-31360 Fixed
Mikhail Zarechenskiy