If inline function A calls another inline function B,
we must use the original version of inline function A for inlining,
which doesn’t have inlined function B. Because during the inlining
process, we remap all occurrences of inline function A
to a temporary copy of function A, and if the function B
somehow uses function A (e.g. callable reference),
the built IR will have a reference to the temporary function,
not the original one. All these things lead to broken cross-module references.
This patch saves the original versions of all inline functions
before inlining and provides them during the inline process.
^KT-55930 Fixed
If a lambda expression does not capture any local variables, convert
it to a global free function and replace the lambda creation with
a reference to that function.
Example: for the following Kotlin code
```kotlin
fun foo(f: () -> Unit) = f()
fun bar() = foo { console.log("hello") }
```
before this patch, we generated:
```js
function foo(f) {
return f();
}
function bar() {
return foo(bar$lambda());
}
function bar$lambda() {
return function () {
console.log('hello');
};
}
```
after this patch, we generate:
```js
function foo(f) {
return f();
}
function bar() {
return foo(bar$lambda);
}
function bar$lambda() {
console.log('hello');
}
```
Fixed by outlining JS code that uses Kotlin variables making usages of
these locals explicit and preventing bugs due to one-sided variable renaming.
This prevents using Kotlin variables as lvalue in JS code.
Account for JsExport in legacy backend namer. It means we
catch overloaded exported function conflicts for free!
Add error diagnostics:
* NESTED_JS_EXPORT (Fixes KT-36798)
* WRONG_EXPORTED_DECLARATION (Part of the fix for KT-37752)
* NON_EXPORTABLE_TYPE (Fixes KT-37771)
Consider an import from an inline function invocation. If it is
being called from another inline function, it should be defined
in a special way (e.g. `$$importsForInline$$.foo`) so that
the compiler knows where to load transitive dependencies from.
What's more, the declaration itself should be inside the inline
function wrapper.
Otherwise it should be defined in a regular way (e.g.
`$module$bar.foo` among other top-level imports).
By default the imports are loaded in the first form, and
transformed into the second one when needed. To check
whether this transformation the following predicate is
used: `inlineFunctionDepth == 0`.
At the moment the mentioned variable is increased upon
visiting an inline function declaration (`defineInlineFunction`),
and upon visiting an unknown (not visited before) inline function invocation.
It seems that instead the variable should be increased when processing
an existing inline function wrapper. At that point a new place to
put import definitions (`statementContextForInline`) is set.
Due to way JS code is generated (lambda's come before their call sites)
this issue seems to have been masked. Primary class constructors are a special
case - they come before any other declaration within. Hence a lambda
invocation inside a constructor leads to incorrect import definition.
Artem Kobzar