Hey I'm working on a compiler plugin in the analysis phase, and I'm doing some annotation processing. I have an annotation with a KtValueArgumentList, and I'm trying to either resolve the value of a contained value argument, or the fully qualified name. I've tried getting the type out of the bindingContext, but it consistently returns null (maybe it's not available during analysis?).

ContextExpressionEvaluator.getConstant()

also seems to return null. Any insight into what I could do to resolve the reference to either a fully qualified name or extract the value would be appreciated!

Hi, if my compiler plugin runs on a multiplatform project (jvm with IR & macos), how can I reference common stdlib classes like

HashMap

?

pluginContext.referenceClass(FqName("kotlin.collections.HashMap"))

• On JVM returns

null

• On Macos (K/N) returns the symbol Since

HashMap

is a typealias to

java.util.HashMap

I thought using

pluginContext.referenceTypeAlias(FqName("kotlin.collections.HashMap"))

could work but it's behaving differently • ON JVM it throws

AssertionError: Package or class expected: typealias HashMap; for K
t org.jetbrains.kotlin.ir.declarations.lazy.IrLazyDeclarationBase$createLazyParent$1.invoke(IrLazyDeclarationBase.kt:70)

• On K/N (macos) it returns

null

How can one reference an available common class from the stdlib like

kotlin.collections.HashMap

? The only work around I can see is to test if

pluginContext.referenceClass(FqName("java.util.HashMap"))

returns null, which indicates I'm running the compiler plugin within a K/N context and fallback to

pluginContext.referenceClass(FqName("kotlin.collections.HashMap"))

... Any thoughts appreciated 🙂

I'm emitting an

IrTypeOperatorCallImpl

instruction with an

operator = IMPLICIT_NOTNULL

This works fine on JVM platform, however for K/N it throws

e: kotlin.NotImplementedError: An operation is not implemented: TYPE_OP type=MyClassFoo origin=IMPLICIT_NOTNULL typeOperand=MyClassFoo
	at org.jetbrains.kotlin.backend.konan.llvm.CodeGeneratorVisitor.evaluateTypeOperator(IrToBitcode.kt:1351)

Browsing K/N repo I found that indeed this is not supported

TODO(ir2string(value))

is this a known issue? is there a work around this? https://github.com/JetBrains/kotlin-native/blob/master/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/IrToBitcode.kt#L1353

is there a discussion of having the compiler do something to convert

someMap[key]!!...

into

someMap.getValue(key)...

?

Hello! I've written Kotlin compiler plugin, that add main method using IrFile.addFunction. in 1.4.20 it was removed. Please, advise me for alternatives.

I have a question kind of about compiler and kind of about YouTrack. I have a use case where I need to suppress

ERROR

and

HIDDEN

deprecation level compiler errors for generic parameter on a deprecated class itself. More info here – https://youtrack.jetbrains.com/issue/KT-34480#focus=Comments-27-4558822.0-0. Is this something that could be added? A follow-up question is about YouTrack. I found the linked issue but the person that, I think, was handling it is now banned. How such old-ish and stale issues are handled by JetBrains? Is anyone from JB team notified about it or is there some procedure to bring issues up?

Hi, is there a method to parse a File into a IrFile ? (I know that i can get IrFiles with IrGenerationExtension, but that compile phase is too late for my usecase)

I am trying to explore LLVM a bit, but I fail to find good examples of how to use it. I heard Kotlin/Native uses LLVM as the back-end of its compiler so I thought about taking a look at the https://github.com/JetBrains/kotlin-native repository to see if I could find how the Kotlin/Native compiler generates LLVM IR and which IR instructions it uses. However, I am totally lost in that project and have no clue where to actually look for what I want to find. Can anyone point me to where the LLVM IR generation is and how the compiler invokes it? And couldd I perhaps use the Kotlin/Native compiler itself as a library to generate the LLVM IR for me?

Hi, I was wondering if this is expected behavior or I should file a bug. I looked in youtrack but could not find a similar one. https://pl.kotl.in/3m3uiVtjK

The cause is this other exception:

java.lang.IllegalStateException: Error type encountered: [ERROR : <ERROR FUNCTION RETURN TYPE>] (DeferredType)

It's not an informative message, to my eyes, unfortunately.

Hi, i try to get all methods from a

ClassDescriptor

, but when i use

(AInstance as ClassDescriptor).unsubstitutedMemberScope.getContributedDescriptors().filterIsInstance<FunctionDescriptor>()

will get all default functions, such as

toString

euqals

. Is there any better method to get all member methods including static methods?

Are there any examples how to decompile FIR (FirElement) to source code String?

Can we get the relevant information of whether a method is a static or normal from an instance of

JavaMethodDescriptor

?

Apologies if OOT in this channel or if there is an existing issue already that i couldn't find , but i would like to understand if the following behaviour is expected. Here is a MWE to illustrate my problem.

fun minimalExample(
  ids : List<Long>,
  details : Map<String, Boolean>
) : List<Boolean?> =
  ids.map { id -> details.get(id) }

I'm mapping over a list of

Longs

and for each

Long

i try to access the corresponding value from a key-value map; the map however here is of type

Map<String, Whatever>

, not

Map<Long, Whatever>

I've done that on purpose so that when writing

details.get(id)

the types don't match I would have expected the compiler to throw a compilation error, something like

type mismatch: inferred type is Long but String was expected

Instead i can compile the code and run it (obviously at runtime there is jvm type erasure on generic and details.get(id) will always return null in this case). there is a warning

warning: type inference failed. The value of the type parameter K should be mentioned in input types (argument types, receiver type or expected type). Try to specify it explicitly.

the problem with this warning is two fold: 1. it's error prone. I can handle all warnings as errors, or set a linter, but i would have expected the inference to work just fine in this example 2. there seems to be no obvious way to me to provide the extra information that the compiler would need in order for the type inference to work. is this behaviour expected or is an issue?

Hi, I'm working on a kotlin compiler plugin. One of the tasks of the plugin is to replace certain interfaces with a class. E.g.:

inteface Greeting {
  fun greet()
}

Would be transformed into a class replacing the interface:

class Greeting {
  fun geet() {
    println("Hello, World!")
  }
}

When trying to figure out whether I can to this and mostly how, I looked at [arrow-meta](https://github.com/arrow-kt/arrow-meta). I see they accomplish replacing/renaming pieces of kotlin code in a

AnalysisHandlerExtension

. They also build their own AST and have their own writer to write the modified tree into a file. So I though instead of relying on arrow-meta I thought I'd use the PSI api to copy, modify and get the text of modified files. However it seems that in the compiler some pieces of PSI is not available. Most importantly when I try to delete and element from the tree I get the following exception:

e: java.lang.NullPointerException
        at org.jetbrains.kotlin.com.intellij.psi.impl.source.codeStyle.CodeEditUtil.saveWhitespacesInfo(CodeEditUtil.java:122)
        at org.jetbrains.kotlin.com.intellij.psi.impl.source.codeStyle.CodeEditUtil.removeChildren(CodeEditUtil.java:134)
        at org.jetbrains.kotlin.com.intellij.psi.impl.source.codeStyle.CodeEditUtil.removeChild(CodeEditUtil.java:49)
        at org.jetbrains.kotlin.com.intellij.psi.impl.source.tree.CompositeElement.deleteChildInternal(CompositeElement.java:451)
        at org.jetbrains.kotlin.com.intellij.extapi.psi.ASTDelegatePsiElement.deleteChildInternal(ASTDelegatePsiElement.java:346)
        at org.jetbrains.kotlin.com.intellij.extapi.psi.ASTDelegatePsiElement.delete(ASTDelegatePsiElement.java:330)

Looking at

CodeEditUtil

I know that the

NullPointerException

is raised in this part

public static void saveWhitespacesInfo(ASTNode first) {
  ...
  setOldIndentation((TreeElement)first, IndentHelper.getInstance().getIndent(file, first));
}

Because

IdentnHelper.getInstance()

returns null.

public abstract class IndentHelper {
  public static IndentHelper getInstance() {
    return ApplicationManager.getApplication().getService(IndentHelper.class);
  }
  ...
}

And indeed trying to get

IndentHelper

as service returns null in my plugin. So now I'm wondering if it is possible to install an instance if this service out side of the IDE to be able to manipulate PSI in a kotlin compiler plugin. Alternatively I'd be also grateful is someone could provide me with the highlights on an alternative approach to achieve my goal.

Are there any IrDeclaration implementations without visibility?

Hi all. I'm trying to write a compiler plugin that tracks which jars dependencies are loaded from. Is an `AnalysisHandlerExtension`the right kind of extension to do this? I'm having trouble finding an API that is able to tied a KtType back to the jar it was loaded from. Any pointers appreciated 🙂

Hi all! I need help. I am creating a compiler plugin in which I adjust property declarations if they are annotated with a specific annotation. Problem: I need to filter properties by annotations. At the moment, I have access to

org.jetbrains.kotlin.psi.KtProperty

, form which I need to get annotations. So far, I found a way to do it like this:

property.annotationEntries.any {
        it.typeReference
            ?.typeElement
            ?.safeAs<KtUserType>()
            ?.referencedName == "MyAnnotation"
    }

But

referencedName

doesn't return a fully qualified name (

MyAnnotation

instead off

com.example.MyAnnotation

) Question: How to check if a

KtProperty

is annotated with a particular annotation?

Is there a canonical way to request exposing an API in IR? I'd like to reuse some code from data class generation but it uses an internal

GeneratorContext

API that looks pretty generally useful

Heyo, how would one build a IrCall with a vararg as value parameter?

Hi there!, I’m trying to get a hold of the descriptor or IR node for

kotlin.Int.plus

. I’m currently using with no luck the following code which returns other

plus

functions like the ones for collections, BigInteger and String but nothing for

Int

builtIns.builtInPackagesImportedByDefault.flatMap {
    it.memberScope.getContributedDescriptors { true }
}

Any help on how to get a hold of those descriptors is appreciated. Thanks!

Hi all. I'm currently writing a compiler plugin which needs to extract the assignment of certain properties from the source files. The problem is i always need to be able to extract those assignments for all files. But when the current run is incremental, i only get the new/changed files. My current way of doing this is to provide a

DeclarationChecker

which extracts the

assignmentPsi

from the `PropertyDescriptor`'s. Is there another hook or a better way with which i can do this for all source files not just those that have changed since the last run? I just need this to work on the JVM.

Truth in advertising: I know zip about the compiler but I want and need to know a lot more. My goal is to learn enough about the compiler to work on a Kotlin LSP server and do useful things. I could tell you more but you'd likely die of boredom if I elaborated. Please excuse my abuse/misuse of terminology as I learn and do direct me to code/documentation/etc so I can ask better questions. So here's the most direct question I can come up with: if I have a callable reference node (PsiElement), is there a way I can access the associated declaration at the time I see the reference node? I'm guessing that I can since the compiler must know about a declaration before it can label an identifier as a callable reference. The callable reference is a "println" in case it matters.

It may be stupid/newbie question, but can I use contracts to check if method arguments are < 0?

fun foo(param:Int) {
// old school, but could we use a contract here to get compiler error at callsite for foo(-1) instead?
require(param >1)

// do something great
println(param)
}

Hi everybody! I am trying to modify annotations of a property getter. The idea is that I add a new annotation to a property if conditions match. I am overriding

IrElementTransformerVoidWithContext.visitPropertyNew()

and my code looks somewhat like this:

override fun visitPropertyNew(declaration: IrProperty): IrStatement {
    declaration.getter?.let {
        it.annotations = it.annotations + aNewAnnotationEntry
    }
    return super.visitPropertyNew(declaration)
}

Problem: This works well for all properties but not for properties of data classes. Question: How do I add an annotation to a getter of a property of a data class declared in its constructor?

Where could I find a jar of sources or Javadoc for

kotlin-embeddable-compiler

? Shipped version in maven contains empty jars: https://repo1.maven.org/maven2/org/jetbrains/kotlin/kotlin-compiler-embeddable/1.4.21/

when is EOL on kotlin requiring 1.6,7,8,9 specific jdk support to build? is 1.8 good enough ? or jdk 11 ?

how many iterations until "Many programming languages have self-hosted implementations: compilers that are both in and for the same language. Such languages include Ada, BASIC, C, C++,[4] C#,[5] ClojureScript,[6] CoffeeScript, Crystal, D, Dylan, F#, FASM, Forth, Gambas, Go, Haskell, HolyC, Java, Lisp, Modula-2, OCaml, Oberon, Pascal, Python, Rust, Scala, Smalltalk, TypeScript, Vala, and Visual Basic"+=" Kotlin"

👋 Is it possible to write a compiler plugin that adds a Builder pattern a la lombok's @Builder? I understand that it's not needed if you stay in the Kotlin world, but for migrating a large codebase that uses lombok to Kotlin, it would help a lot if you could use builders in Java to create instances of Kotlin classes.

Has anyone already tried to use IR to compile Kotlin to a different language yet?