Both for callables obtained via reflection API (KClass.members etc) and
for callables obtained via ::-references, the instance parameter is now
the class which was used to construct the type at the left-hand side of
the reference, NOT the class where the callable is originally declared
as is known at compile-time. The reason is to reduce the difference in
behavior of KCallable.call vs FunctionN.invoke: the latter always
required the subclass instance for a fake override, and it's reasonable
that the former would require it as well.
Note that in Java reflection, behavior could differ in a similar case.
For a simple fake override, Class.getMethod would return the method
declared in the base class and that method will accept instances of the
base class in invoke. However, it's difficult to rely on this behavior
because if there's a bridge for a fake override in the derived class
(e.g. when overridden members have different signatures), the returned
Method object is accepting the derived class as the receiver. This just
confirms the fact that Java reflection operates on a different level of
abstraction, namely JVM methods in .class files, which is not applicable
to our use cases directly. Another reason not to replicate Java
reflection's behavior is the uncertainty as to which member is returned
in case there are several in the hierarchy for a given fake override:
see the "otherwise one of the methods is chosen arbitrarily" note in
javadoc on Class.getMethod.
#KT-24170 Fixed
- Add marker for the experimental type inference features
- Add annotation that will control builder-like inference
- Require that annotation on corresponding parameters and extensions
- Allow to use builder inference without suspendability
Changes in tests and refactorings (rename mainly) are going to be
introduced in further commits
Before Kotlin 1.3-M2 we didn't write `has_field` flag for constants
inside multifile classes. Now we write and rely on this when
trying to load constant initializers, which is totally fine for
binaries that were compiled with the 1.3-M2 or newer version.
Unfortunately, constant initializers will not be loaded for old binaries.
One way is to avoid relying on this flag, but then we'll get other
problems (e.g. 3345dc81fd).
Therefore, for binaries that were compiled with at least 1.3-M2 version,
we'll rely on the flag, otherwise, we won't.
Having a map from ModuleDescriptor leads to modules leakage
Especially, it's critical for DefaultBuiltins which is used in JS
ModuleDescriptor's instances were leaked there forever until the daemon dies
(up to 350M while compiling Kotlin project itself)
Also fix a bug where nullability of the assigned value was not checked
in ClassCompanionFieldSetter because it wasn't a subclass of FieldSetter
where this check occurred
Reflection expects to see a callable method for a hidden constructor,
thus, it should be a synthetic accessor.
JVM method signature in metadata should point to the synthetic accessor.
Annotations for hidden constructor should be written on the synthetic
accessor.
Preface: Kotlin 1.3 will be able to read metadata of .class files
produced by Kotlin 1.4 (see KT-25972). Also, to simplify implementation
and to improve diagnostic messages, we're going to advance JVM metadata
version to 1.4.0 in Kotlin 1.4, and would like to keep it in sync with
the compiler version thereafter. This presents a problem: in an unlikely
event that before releasing 1.4, we find out that the metadata-reading
implementation in 1.3 was incorrect, we'd like to be able to fix the bug
in that implementation and _forbid_ 1.3 from reading metadata of 1.4.
But prior to this commit the only way to do this was to advance the
metadata version, in this case to 1.5, and that breaks the
metadata/compiler version equivalence we'd like to keep.
The solution is to add another boolean flag to the class file, called
"strict metadata version semantics", which signifies that if this class
file has metadata version 1.X, then it can only be read by the compilers
of versions 1.X and greater. This flag effectively disables the smooth
migration scenario proposed in KT-25972 (as does increasing metadata
version by 2), and will be used only in hopeless situations as in the
case described above.
* The members of Result are isSuccess, isFailure, exceptionOrNull, getOrNull
* The rest of API is implemented via inline-only extensions
* There are two internal functions to hide detailed mechanics of an internal
Result.Failure class: createFailure and throwOnFailure
* Result.toString is explicit: either Success(v) or Failure(x)
See KT-26538
Otherwise we're not trying to load annotations on the parameter of the
property setter in MemberDeserializer.loadProperty.
Note that after this commit, we could now also assume that if
getter/setter is default, it has no annotations, and thus use
Annotations.EMPTY for default getter/setter in loadProperty. However,
this would cause reflection to work incorrectly on classes compiled by
an older Kotlin compiler, so we'll still try to load annotations on
default accessors for an indefinite time.
#KT-25499 Fixed
In MemberDeserializer.loadProperty, we incorrectly passed 0 to
getAnnotations when loading annotations on property accessors in case
the protobuf field getter_flags/setter_flags was not present. The
correct behavior, as described in metadata.proto, was to pass a special
"default accessor flags" value, constructed from the main property
flags. Otherwise in case there were annotations both on the property and
on the accessor (as in PropertyAndAccessor.kt) and the accessor was
otherwise default, we would assume that it had no annotations and would
not load them in compiler and reflection
#KT-25499 In Progress
<IMPL_SUFFIX> for method is a method signature hash,
if method value parameter types contain inline class types,
otherwise 'impl'.
Constructor methods are named as 'constructor-<IMPL_SUFFIX>'.
Synthesized 'box' and 'unbox' methods are named as
'<METHOD_NAME>-<IMPL_SUFFIX>'.
Erased implementations of overriding and non-overriding methods
are named as '<METHOD_NAME>-<IMPL_SUFFIX>'.
Fully specialized implementation of 'equals' will have a special suffix.
Minimize AnnotationsImpl to leave it usable in simple scenarios where
there's no use-site targeted annotations, and use TargetedAnnotations in
the only place in the frontend (AnnotationResolverImpl) where use-sites
were needed.
Also, delete kdoc on Annotations.isEmpty to prevent readers from putting
too much thought into how it works. With the exception of a few places
in the frontend where use-site targeted annotations are still accessed
via the Annotations object, it's now an implementation detail and users
(such as backends, IDE) should not care about them at all, and instead
should just deal with the correct element when processing annotations
Dmitry Petrov