Apparently if you add an empty line at the start of the FIR file, that's
not enough of a difference for the test suite to complain about, but
enough for it to not add the FIR_IDENTICAL directive...
While it is theoretically useful to know that `{ while(true) {} }`
returns Nothing, CFG node deadness is not precise enough to do that: if
the entire lambda is dead, it's no longer possible to find out whether
the loop is terminating. Besides, `while (true)` and `if (true)` are
pretty much the only constructs like that anyway.
Note that this commit does not affect resolution for lambdas that end in
a Nothing-returning expression, e.g. `throw`.
* `return` should only be added to the last statement if the return
type is not Unit
* If there is a `return` without an argument, then the expected return
type is Unit and the last expression is not a return argument (unless
it's an incomplete call, in which case it is inferred to return Unit;
this behavior is questionable, but inherited from K1)
* There should be a constraint on return arguments even if the expected
type is Unit, otherwise errors will be missed
* When the expected type is known, using the call completion results
writer is pointless (and probably subtly wrong).
^KT-54742 Fixed
- If too few or too many type arguments were provided, they were all
thrown away in `TypeArgumentMapping`,
`FirCallCompletionResultsWriterTransformer`, and `KtFirCallResolver`.
The fix handles type arguments of the wrong arity more gracefully.
- Note for `TypeArgumentMapping`: Excess type arguments are not needed
for candidate resolution. Excess type arguments are still resolved
due to the handling in `FirCallCompletionResultsWriterTransformer`.
- Post-processing in `AllCandidatesResolver`: When all candidates are
resolved in `AllCandidatesResolver.getAllCandidates`, the function
builds a FIR file. During that resolution, the
`generic<String, String>` call (in example
`functionCallWithTooFewTypeArguments.kt`) is correctly marked as
inapplicable, but the missing type argument is inferred as an error
type. `firFile` then contains a function call
`generic<String, String, ERROR>` instead of `generic<String, String>`.
This call is still marked as inapplicable. Despite that, the
*subsequent* resolution by
`bodyResolveComponents.callResolve.collectAllCandidates` disregards
the call's inapplicability and resolves successfully into an
applicable candidate. This is because `CandidateFactory` doesn't make
any guarantees for already inapplicable calls. The fix adds
post-processing to `AllCandidatesResolver` to preserve candidate
inapplicability.
- Most tests that this commit changes had slightly different results due
to type arguments becoming resolvable.
- `wrongNumberOfTypeArguments.kt` and
`wrongNumberOfArgumentsInTypeAliasConstructor.kt`:
`ConeDiagnostic.toFirDiagnostics` prefers specific errors. Because
`ARGUMENT_TYPE_MISMATCH` is specific and `INAPPLICABLE_CANDIDATE` is
not, only the former is reported. I see no reason to pass an illegally
typed argument in either test, so the change reduces the errors to
`INAPPLICABLE_CANDIDATE`.
- `typeAliasSamAdapterConstructors2.fir.kt`: See KT-55007.
- Disable `mismatchTypeParameters` JS backend test due to its handling
of excess type arguments. See KT-55250.
^KT-54980 fixed
- LL FIR uses `ReturnTypeCalculatorWithJump` by default because it
cannot guarantee that the implicit types of non-local functions
referenced in a function `f` have been resolved during body resolve
of `f`.
- However, if `ReturnTypeCalculatorWithJump` encountered a local
function, it tried to resolve its return type even during body
resolve of that same local function. The fix delegates to
`ReturnTypeCalculatorForFullBodyResolve`, which should be used for
local declarations.
^KT-55327 fixed
^KT-55324 fixed
Incompatible supertypes check also don't provoke runtime problems
in most situations, because this check is also bound to type argument
conflict. Related to KT-54411
The situations with conflicting type arguments normally don't provoke
any runtime problems. Also, conflicts like A<T> VS A<SomeType> aren't
valid at all. Here we decided to remove them to avoid strange
and non-actionable warnings in user code.
#KT-54411 Fixed
Otherwise, exception from org.jetbrains.kotlin.resolve.calls.inference.components.ConstraintInjector.TypeCheckerStateForConstraintInjector.fixedTypeVariable
might happen during forks resolution
The test data is extracted from intelliJ FP test
^KT-43296 Fixed
Otherwise, OVERLOAD_RESOLUTION_AMBIGUITY is reported for the calls to
the functions annotated as @OverloadResolutionByLambdaReturnType
^KT-43296 In Progress
The idea is that we should not fix (i.e. choose any of the fork branches)
on the stage of candidate processing before completion, but it's enough
just to check that current state can be converged to success.
And when completion starts, and we add expected type to the system,
we've got more information to choose the correct fork branch.
NB: The old `processForkConstraints` is being called just
at the beginning of the completion phase.
^KT-43296 In Progress
Report an error that inference will change and type has to be provided
manually in other language versions, since the current behavior is an
unsoundness that can cause runtime NPEs while the new behavior may
silently change overload resolution.
^KT-30054 Fixed
It's reported on receivers in extension function calls with stub type,
as such calls can shadow members of finalized stub types causing
change of resolve when corresponding type argument specified explicitly
It works by checking extension receiver during call resolution parts run
That way we can easily detect if we found an extension applicable to
stub receiver and report call diagnostic for it
KT-53739
Let's call builder lambdas (BL) a lambda that has non-fixed input type
projection at the moment of lambda arguments analysis, such lambdas
is a subject to be analyzed with builder inference
Due to bug in constraint system joining algorithm, currently system
of two or more such lambdas may lead to unsound type inference
Diagnostic added here should be reported in case when there are two
BL that shares a common constraint system, while not annotated with
@BuilderInference, as a protection against aforementioned bug
It's reported by ConstraintSystemCompleter when such situation has
occurred during builder inference phase, it is the same place that
decides wherever lambdas is subject to builder inference or not
KT-53740
In K1, upper bound violated causes candidate to have lower applicability
due to constraint errors, in K2 however constraint errors has to be
reported explicitly
Denis.Zharkov