The compiler should only report diagnostics for
comparisons over builtins and identity-less types,
other incompatibilities should be reported
via inspections.
It's ok that in `equalityChecksOnIntegerTypes`
instead of `EQUALITY_NOT_APPLICABLE_WARNING` we get
`EQUALITY_NOT_APPLICABLE`, because
`ProperEqualityChecksInBuilderInferenceCalls`
is already active by default.
This change also replaces the notion of a representative superclass
with the least upper bound.
This makes complex types like
intersection/flexible transparent to
RULES1-based compatibility checks.
One way to look at it is to think
that this is an automatic way of handling
type parameters: automatic picking of
"interesting" bounds, and checking them against one another.
Note that `TypeIntersector.intersectTypes`
for `Int` and `T` where `T` is a type parameter
may return both `{Int & T}` or `null`
depending on `T`-s bounds. At the same time,
for type parameters `T` and `K` it will
always return `{T & K}`.
`ConeTypeIntersector.intersectTypes`, on the
other hand, will always return `{Int & T}`
irrespectively of the bounds. Meaning, the two
intersectors differ in corner cases.
`lowerBoundIfFlexible` call in `isLiterallyTypeParameter` is backed by
the `equalityOfFlexibleTypeParameters` test.
^KT-35134 #fixed-in-k2
^KT-22499 #fixed-in-k2
^KT-46383 #fixed-in-k2
In order to make resolution still work for members not available from
`Nothing`, we track the type without `Nothing?` and use that for
resolution instead.
candidate is not an infix function.
This mirrors FE 1.0 (see
`AbstractTracingStrategy.reportUnsafeCallOnBinaryExpression()`) and
allows consistent handling for quickfixes on infix calls.
This directive anyway does not make test run twice with OI, and with NI
It only once run the test with specific settings (// LANGUAGE)
and ignores irrelevant (OI or NI tags)
Added checker for FirEqualityOperatorCall. It's surfaced as one of the
following diagnostics depending on the PSI structure and types under
comparison:
* INCOMPATIBLE_TYPES(_WARNING)
* EQUALITY_NOT_APPLICABLE(_WARNING)
* INCOMPATIBLE_ENUM_COMPARISON_ERROR
Comparing with FE1.0, the current implementation is more conservative
and only highlights error if the types are known to follow certain
contracts with `equals` method. Otherwise, the checker reports warnings
instead.
However, the current checker is more strict in the following situations:
1. it now rejects incompatible enum types like `Enum<E1>` and
`Enum<E2>`, which was previously accepted
2. it now rejects incompatible class types like `Class<String>` and
`Class<Int>`, which was previously accepted
3. the check now takes smart cast into consideration, so
`if (x is String) x == 3` is now rejected
Previously if an unsafe call is to an overloaded function, FIR checkers
report NONE_APPLICABLE. This change instead report them as UNSAFE_CALL
or its variants.
Currently if there is an error in a function call, FIR would report the
entire expression if this call is qualified, but *only* the name if it's
not qualified. For example, assume the following two calls are all
contains some errors.
```
a.foo(1,2,3)
^^^^^^^^^^^^
bar(1,2,3)
^^^
```
The entire call of `foo` is reported since it's qualified. But only the
reference `bar` is reported since it's not qualified. This limits the
usage of position strategies because the IDE does not allow position
strategies to go outside of the initially reported PSI element
(org.jetbrains.kotlin.idea.fir.highlighter.KotlinHighLevelDiagnosticHighlightingPass#addDiagnostic).
This change passes both the original error named reference and the
surrounding qualified access expression and defer the decision of which
to use to the reporting logic.
For unresolved reference and checks on `super` keyword, the position
strategy should not highlight the surrounding parentheses. Hence a new
position strategy `REFERENCED_NAME_BY_QUALIFIED` is added.
In addition, this change also has the following side effect
* some diagnostics are no longer reported when there is a syntax error
since the higher level structure does not exist when there is a syntax
error