Optimize imports to classes when there's an import of a type alias to
that class with the same name. This results in "java.lang.*" imports
being optimized in favor of the corresponding type aliases in "kotlin.*"
which are imported by default
Previously, packages `java.lang` and `kotlin.jvm` were imported on JVM
by default on the same rights, causing problems when the same classifier
existed both in `java.lang` and `kotlin.jvm`. Since the only known case
of such conflict were type aliases to JVM classes, the corresponding
classes (expansions of those type aliases) were manually excluded from
default imports. This made the code in DefaultImportProvider complicated
and resulted in multiple problems, regarding both correctness and
performance (see 82364ad3e5, a9f2f5c7d0, dd3dbda719).
This change adds a new concept, a "low priority import", and treats
`java.lang` as such. Since these imports are now separated from the rest
of default imports in LazyImportScope via secondaryClassImportResolver,
conflicts between classifiers are handled naturally: the one from
`kotlin.jvm` always wins (unless the one from `java.lang` is imported
explicitly, of course). This approach is simpler, safer and does not
require any memory to cache anything.
Skip ResolveToJava.kt test for javac-based resolve; it now fails because
of a weird issue which I didn't have time to investigate (this is OK
because it's a corner case of an experimental functionality)
The implementation is a bit obscure because this worked on JS since
Kotlin 1.0 and we should not break that; however, on JVM, a diagnostic
will be reported with old language/API version
#KT-25241 Fixed
Caused by 4266e50be8 and 8ccbbf71ec. Previously it worked because we
used hardcoded signatures of equals/hashCode/toString and always looked
them up in java.lang.Object
#KT-25404 Fixed
Do not pass the jars for modules such as descriptors, descriptors.jvm,
etc to `--module-path` because javac assumes that these are separate
modules (even though they're listed later as parts of this module in
`--patch-module), and prohibits to have split packages and foreign
service implementations among them
Mikhael Bogdanov