FIR: don't change explicitly given anonymous function type

compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/ir/Fir2IrTextTestGenerated.java

@@ -2494,6 +2494,12 @@ public class Fir2IrTextTestGenerated extends AbstractFir2IrTextTest {
             runTest("compiler/testData/ir/irText/firProblems/FlushFromAnonymous.kt");
         }
 
+        @Test
+        @TestMetadata("functionLiteralGenericSignature.kt")
+        public void testFunctionLiteralGenericSignature() throws Exception {
+            runTest("compiler/testData/ir/irText/firProblems/functionLiteralGenericSignature.kt");
+        }
+
         @Test
         @TestMetadata("ImplicitReceiverStack.kt")
         public void testImplicitReceiverStack() throws Exception {

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/body/resolve/FirDeclarationsResolveTransformer.kt

@@ -747,6 +747,7 @@ open class FirDeclarationsResolveTransformer(transformer: FirBodyResolveTransfor
             )
         }
         var lambda = anonymousFunction
+        val initialReturnTypeRef = lambda.returnTypeRef
         val valueParameters = when {
             resolvedLambdaAtom != null -> obtainValueParametersFromResolvedLambdaAtom(resolvedLambdaAtom, lambda)
             else -> lambda.valueParameters
@@ -788,17 +789,22 @@ open class FirDeclarationsResolveTransformer(transformer: FirBodyResolveTransfor
             (it as? FirExpression)?.typeRef is FirImplicitUnitTypeRef
         }
 
-        val returnType =
+        val returnType = when {
-            if (implicitReturns.isNotEmpty() || lambda.returnType?.isUnit == true) {
+            initialReturnTypeRef is FirResolvedTypeRef -> {
+                initialReturnTypeRef.coneType
+            }
+            implicitReturns.isNotEmpty() || lambda.returnType?.isUnit == true -> {
                 // i.e., early return, e.g., l@{ ... return@l ... }
                 // Note that the last statement will be coerced to Unit if needed.
                 session.builtinTypes.unitType.type
-            } else {
+            }
+            else -> {
                 // Otherwise, compute the common super type of all possible return expressions
                 session.typeContext.commonSuperTypeOrNull(
                     returnStatements.mapNotNull { (it as? FirExpression)?.resultType?.coneType }
                 ) ?: session.builtinTypes.unitType.type
             }
+        }
         lambda.replaceReturnTypeRef(
             lambda.returnTypeRef.resolvedTypeFromPrototype(returnType).also {
                 session.lookupTracker?.recordTypeResolveAsLookup(it, lambda.source, null)

compiler/testData/codegen/box/reflection/genericSignature/functionLiteralGenericSignature.kt

@@ -1,6 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
-// FIR status: Fail, expected: kotlin.jvm.functions.Function1<java.util.List<java.lang.Double>, java.util.List<java.lang.Integer>>,
-// actual: interface kotlin.jvm.functions.Function1
 // TARGET_BACKEND: JVM
 
 import java.util.Date

compiler/testData/diagnostics/tests/declarationChecks/ScalaLikeNamedFun.fir.kt

@@ -3,16 +3,16 @@
 
 fun test1(): Int = <!RETURN_TYPE_MISMATCH!>{ <!RETURN_NOT_ALLOWED!>return<!> 1 }<!>
 fun test2(): Int = <!RETURN_TYPE_MISMATCH!>{ 1 }<!>
-val test3: () -> Int = <!INITIALIZER_TYPE_MISMATCH!>fun (): Int = { <!RETURN_NOT_ALLOWED!>return<!> 1 }<!>
+val test3: () -> Int = fun (): Int = { <!RETURN_NOT_ALLOWED!>return<!> 1 }
-val test4: () -> Int = <!INITIALIZER_TYPE_MISMATCH!>fun (): Int = { 1 }<!>
+val test4: () -> Int = fun (): Int = { 1 }
 fun test5(): Int { return <!RETURN_TYPE_MISMATCH!>{ 1 }<!> }
 fun test6(): Int = <!RETURN_TYPE_MISMATCH!>fun (): Int = 1<!>
 
 fun outer() {
     fun test1(): Int = <!RETURN_TYPE_MISMATCH!>{ <!RETURN_NOT_ALLOWED!>return<!> 1 }<!>
     fun test2(): Int = <!RETURN_TYPE_MISMATCH!>{ 1 }<!>
-    val test3: () -> Int = <!INITIALIZER_TYPE_MISMATCH!>fun (): Int = { <!RETURN_NOT_ALLOWED!>return<!> 1 }<!>
+    val test3: () -> Int = fun (): Int = { <!RETURN_NOT_ALLOWED!>return<!> 1 }
-    val test4: () -> Int = <!INITIALIZER_TYPE_MISMATCH!>fun (): Int = { 1 }<!>
+    val test4: () -> Int = fun (): Int = { 1 }
     fun test5(): Int { return <!RETURN_TYPE_MISMATCH!>{ 1 }<!> }
     fun test6(): Int = <!RETURN_TYPE_MISMATCH!>fun (): Int = 1<!>
 }
@@ -20,16 +20,16 @@ fun outer() {
 class Outer {
     fun test1(): Int = <!RETURN_TYPE_MISMATCH!>{ <!RETURN_NOT_ALLOWED!>return<!> 1 }<!>
     fun test2(): Int = <!RETURN_TYPE_MISMATCH!>{ 1 }<!>
-    val test3: () -> Int = <!INITIALIZER_TYPE_MISMATCH!>fun (): Int = { <!RETURN_NOT_ALLOWED!>return<!> 1 }<!>
+    val test3: () -> Int = fun (): Int = { <!RETURN_NOT_ALLOWED!>return<!> 1 }
-    val test4: () -> Int = <!INITIALIZER_TYPE_MISMATCH!>fun (): Int = { 1 }<!>
+    val test4: () -> Int = fun (): Int = { 1 }
     fun test5(): Int { return <!RETURN_TYPE_MISMATCH!>{ 1 }<!> }
     fun test6(): Int = <!RETURN_TYPE_MISMATCH!>fun (): Int = 1<!>
 
     class Nested {
         fun test1(): Int = <!RETURN_TYPE_MISMATCH!>{ <!RETURN_NOT_ALLOWED!>return<!> 1 }<!>
         fun test2(): Int = <!RETURN_TYPE_MISMATCH!>{ 1 }<!>
-        val test3: () -> Int = <!INITIALIZER_TYPE_MISMATCH!>fun (): Int = { <!RETURN_NOT_ALLOWED!>return<!> 1 }<!>
+        val test3: () -> Int = fun (): Int = { <!RETURN_NOT_ALLOWED!>return<!> 1 }
-        val test4: () -> Int = <!INITIALIZER_TYPE_MISMATCH!>fun (): Int = { 1 }<!>
+        val test4: () -> Int = fun (): Int = { 1 }
         fun test5(): Int { return <!RETURN_TYPE_MISMATCH!>{ 1 }<!> }
         fun test6(): Int = <!RETURN_TYPE_MISMATCH!>fun (): Int = 1<!>
     }

compiler/testData/diagnostics/tests/functionAsExpression/WithGenericParameters.fir.kt

@@ -3,10 +3,10 @@
 interface A
 fun devNull(a: Any?){}
 
-val generic_fun = fun<!TYPE_PARAMETERS_NOT_ALLOWED!><T><!>(t: <!UNRESOLVED_REFERENCE!>T<!>): T = null!!
+val generic_fun = fun<!TYPE_PARAMETERS_NOT_ALLOWED!><T><!>(t: <!UNRESOLVED_REFERENCE!>T<!>): <!UNRESOLVED_REFERENCE!>T<!> = null!!
-val extension_generic_fun = fun<!TYPE_PARAMETERS_NOT_ALLOWED!><T><!><!UNRESOLVED_REFERENCE!>T<!>.(t: <!UNRESOLVED_REFERENCE!>T<!>): T = null!!
+val extension_generic_fun = fun<!TYPE_PARAMETERS_NOT_ALLOWED!><T><!><!UNRESOLVED_REFERENCE!>T<!>.(t: <!UNRESOLVED_REFERENCE!>T<!>): <!UNRESOLVED_REFERENCE!>T<!> = null!!
 
-fun fun_with_where() = fun <!TYPE_PARAMETERS_NOT_ALLOWED!><T><!> <!UNRESOLVED_REFERENCE!>T<!>.(t: <!UNRESOLVED_REFERENCE!>T<!>): T where T: A = null!!
+fun fun_with_where() = fun <!TYPE_PARAMETERS_NOT_ALLOWED!><T><!> <!UNRESOLVED_REFERENCE!>T<!>.(t: <!UNRESOLVED_REFERENCE!>T<!>): <!UNRESOLVED_REFERENCE!>T<!> where T: A = null!!
 
 
 fun outer() {

compiler/testData/ir/irText/firProblems/functionLiteralGenericSignature.fir.ir.txt

@@ -0,0 +1,110 @@
+FILE fqName:<root> fileName:/functionLiteralGenericSignature.kt
+  PROPERTY name:unitFun visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:unitFun type:kotlin.Function0<kotlin.Unit> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=kotlin.Function0<kotlin.Unit> origin=LAMBDA
+          FUN LOCAL_FUNCTION_FOR_LAMBDA name:<anonymous> visibility:local modality:FINAL <> () returnType:kotlin.Unit
+            BLOCK_BODY
+              RETURN type=kotlin.Nothing from='local final fun <anonymous> (): kotlin.Unit declared in <root>.unitFun'
+                GET_OBJECT 'CLASS IR_EXTERNAL_DECLARATION_STUB OBJECT name:Unit modality:FINAL visibility:public superTypes:[kotlin.Any]' type=kotlin.Unit
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-unitFun> visibility:public modality:FINAL <> () returnType:kotlin.Function0<kotlin.Unit>
+      correspondingProperty: PROPERTY name:unitFun visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-unitFun> (): kotlin.Function0<kotlin.Unit> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:unitFun type:kotlin.Function0<kotlin.Unit> visibility:private [final,static]' type=kotlin.Function0<kotlin.Unit> origin=null
+  PROPERTY name:intFun visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:intFun type:kotlin.Function0<kotlin.Int> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=kotlin.Function0<kotlin.Int> origin=LAMBDA
+          FUN LOCAL_FUNCTION_FOR_LAMBDA name:<anonymous> visibility:local modality:FINAL <> () returnType:kotlin.Int
+            BLOCK_BODY
+              RETURN type=kotlin.Nothing from='local final fun <anonymous> (): kotlin.Int declared in <root>.intFun'
+                CONST Int type=kotlin.Int value=42
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-intFun> visibility:public modality:FINAL <> () returnType:kotlin.Function0<kotlin.Int>
+      correspondingProperty: PROPERTY name:intFun visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-intFun> (): kotlin.Function0<kotlin.Int> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:intFun type:kotlin.Function0<kotlin.Int> visibility:private [final,static]' type=kotlin.Function0<kotlin.Int> origin=null
+  PROPERTY name:stringParamFun visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:stringParamFun type:kotlin.Function1<kotlin.String, kotlin.Unit> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=kotlin.Function1<kotlin.String, kotlin.Unit> origin=LAMBDA
+          FUN LOCAL_FUNCTION_FOR_LAMBDA name:<anonymous> visibility:local modality:FINAL <> (x:kotlin.String) returnType:kotlin.Unit
+            VALUE_PARAMETER name:x index:0 type:kotlin.String
+            BLOCK_BODY
+              RETURN type=kotlin.Nothing from='local final fun <anonymous> (x: kotlin.String): kotlin.Unit declared in <root>.stringParamFun'
+                GET_OBJECT 'CLASS IR_EXTERNAL_DECLARATION_STUB OBJECT name:Unit modality:FINAL visibility:public superTypes:[kotlin.Any]' type=kotlin.Unit
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-stringParamFun> visibility:public modality:FINAL <> () returnType:kotlin.Function1<kotlin.String, kotlin.Unit>
+      correspondingProperty: PROPERTY name:stringParamFun visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-stringParamFun> (): kotlin.Function1<kotlin.String, kotlin.Unit> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:stringParamFun type:kotlin.Function1<kotlin.String, kotlin.Unit> visibility:private [final,static]' type=kotlin.Function1<kotlin.String, kotlin.Unit> origin=null
+  PROPERTY name:listFun visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:listFun type:kotlin.Function1<kotlin.collections.List<kotlin.String>, kotlin.collections.List<kotlin.String>> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=kotlin.Function1<kotlin.collections.List<kotlin.String>, kotlin.collections.List<kotlin.String>> origin=LAMBDA
+          FUN LOCAL_FUNCTION_FOR_LAMBDA name:<anonymous> visibility:local modality:FINAL <> (l:kotlin.collections.List<kotlin.String>) returnType:kotlin.collections.List<kotlin.String>
+            VALUE_PARAMETER name:l index:0 type:kotlin.collections.List<kotlin.String>
+            BLOCK_BODY
+              RETURN type=kotlin.Nothing from='local final fun <anonymous> (l: kotlin.collections.List<kotlin.String>): kotlin.collections.List<kotlin.String> declared in <root>.listFun'
+                GET_VAR 'l: kotlin.collections.List<kotlin.String> declared in <root>.listFun.<anonymous>' type=kotlin.collections.List<kotlin.String> origin=null
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-listFun> visibility:public modality:FINAL <> () returnType:kotlin.Function1<kotlin.collections.List<kotlin.String>, kotlin.collections.List<kotlin.String>>
+      correspondingProperty: PROPERTY name:listFun visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-listFun> (): kotlin.Function1<kotlin.collections.List<kotlin.String>, kotlin.collections.List<kotlin.String>> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:listFun type:kotlin.Function1<kotlin.collections.List<kotlin.String>, kotlin.collections.List<kotlin.String>> visibility:private [final,static]' type=kotlin.Function1<kotlin.collections.List<kotlin.String>, kotlin.collections.List<kotlin.String>> origin=null
+  PROPERTY name:mutableListFun visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:mutableListFun type:kotlin.Function1<kotlin.collections.MutableList<kotlin.Double>, kotlin.collections.MutableList<kotlin.Int>> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=kotlin.Function1<kotlin.collections.MutableList<kotlin.Double>, kotlin.collections.MutableList<kotlin.Int>> origin=LAMBDA
+          FUN LOCAL_FUNCTION_FOR_LAMBDA name:<no name provided> visibility:local modality:FINAL <> (l:kotlin.collections.MutableList<kotlin.Double>) returnType:kotlin.collections.MutableList<kotlin.Int>
+            VALUE_PARAMETER name:l index:0 type:kotlin.collections.MutableList<kotlin.Double>
+            BLOCK_BODY
+              RETURN type=kotlin.Nothing from='local final fun <no name provided> (l: kotlin.collections.MutableList<kotlin.Double>): kotlin.collections.MutableList<kotlin.Int> declared in <root>.mutableListFun'
+                CALL 'public final fun CHECK_NOT_NULL <T0> (arg0: T0 of kotlin.internal.ir.CHECK_NOT_NULL?): T0 of kotlin.internal.ir.CHECK_NOT_NULL declared in kotlin.internal.ir' type=kotlin.Nothing origin=EXCLEXCL
+                  <T0>: kotlin.Nothing
+                  arg0: CONST Null type=kotlin.Nothing? value=null
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-mutableListFun> visibility:public modality:FINAL <> () returnType:kotlin.Function1<kotlin.collections.MutableList<kotlin.Double>, kotlin.collections.MutableList<kotlin.Int>>
+      correspondingProperty: PROPERTY name:mutableListFun visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-mutableListFun> (): kotlin.Function1<kotlin.collections.MutableList<kotlin.Double>, kotlin.collections.MutableList<kotlin.Int>> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:mutableListFun type:kotlin.Function1<kotlin.collections.MutableList<kotlin.Double>, kotlin.collections.MutableList<kotlin.Int>> visibility:private [final,static]' type=kotlin.Function1<kotlin.collections.MutableList<kotlin.Double>, kotlin.collections.MutableList<kotlin.Int>> origin=null
+  PROPERTY name:funWithIn visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:funWithIn type:kotlin.Function1<kotlin.Comparable<kotlin.String>, kotlin.Unit> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=kotlin.Function1<kotlin.Comparable<kotlin.String>, kotlin.Unit> origin=LAMBDA
+          FUN LOCAL_FUNCTION_FOR_LAMBDA name:<no name provided> visibility:local modality:FINAL <> (x:kotlin.Comparable<kotlin.String>) returnType:kotlin.Unit
+            VALUE_PARAMETER name:x index:0 type:kotlin.Comparable<kotlin.String>
+            BLOCK_BODY
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-funWithIn> visibility:public modality:FINAL <> () returnType:kotlin.Function1<kotlin.Comparable<kotlin.String>, kotlin.Unit>
+      correspondingProperty: PROPERTY name:funWithIn visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-funWithIn> (): kotlin.Function1<kotlin.Comparable<kotlin.String>, kotlin.Unit> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:funWithIn type:kotlin.Function1<kotlin.Comparable<kotlin.String>, kotlin.Unit> visibility:private [final,static]' type=kotlin.Function1<kotlin.Comparable<kotlin.String>, kotlin.Unit> origin=null
+  PROPERTY name:extensionFun visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:extensionFun type:@[ExtensionFunctionType] kotlin.Function1<kotlin.Any, kotlin.Unit> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=@[ExtensionFunctionType] kotlin.Function1<kotlin.Any, kotlin.Unit> origin=LAMBDA
+          FUN LOCAL_FUNCTION_FOR_LAMBDA name:<no name provided> visibility:local modality:FINAL <> ($receiver:kotlin.Any) returnType:kotlin.Unit
+            $receiver: VALUE_PARAMETER name:<this> type:kotlin.Any
+            BLOCK_BODY
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-extensionFun> visibility:public modality:FINAL <> () returnType:@[ExtensionFunctionType] kotlin.Function1<kotlin.Any, kotlin.Unit>
+      correspondingProperty: PROPERTY name:extensionFun visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-extensionFun> (): @[ExtensionFunctionType] kotlin.Function1<kotlin.Any, kotlin.Unit> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:extensionFun type:@[ExtensionFunctionType] kotlin.Function1<kotlin.Any, kotlin.Unit> visibility:private [final,static]' type=@[ExtensionFunctionType] kotlin.Function1<kotlin.Any, kotlin.Unit> origin=null
+  PROPERTY name:extensionWithArgFun visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:extensionWithArgFun type:@[ExtensionFunctionType] kotlin.Function2<kotlin.Long, kotlin.Any, java.util.Date> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=@[ExtensionFunctionType] kotlin.Function2<kotlin.Long, kotlin.Any, java.util.Date> origin=LAMBDA
+          FUN LOCAL_FUNCTION_FOR_LAMBDA name:<no name provided> visibility:local modality:FINAL <> ($receiver:kotlin.Long, x:kotlin.Any) returnType:java.util.Date
+            $receiver: VALUE_PARAMETER name:<this> type:kotlin.Long
+            VALUE_PARAMETER name:x index:0 type:kotlin.Any
+            BLOCK_BODY
+              RETURN type=kotlin.Nothing from='local final fun <no name provided> (x: kotlin.Any): java.util.Date declared in <root>.extensionWithArgFun'
+                CONSTRUCTOR_CALL 'public constructor <init> () declared in java.util.Date' type=java.util.Date origin=null
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-extensionWithArgFun> visibility:public modality:FINAL <> () returnType:@[ExtensionFunctionType] kotlin.Function2<kotlin.Long, kotlin.Any, java.util.Date>
+      correspondingProperty: PROPERTY name:extensionWithArgFun visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-extensionWithArgFun> (): @[ExtensionFunctionType] kotlin.Function2<kotlin.Long, kotlin.Any, java.util.Date> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:extensionWithArgFun type:@[ExtensionFunctionType] kotlin.Function2<kotlin.Long, kotlin.Any, java.util.Date> visibility:private [final,static]' type=@[ExtensionFunctionType] kotlin.Function2<kotlin.Long, kotlin.Any, java.util.Date> origin=null

compiler/testData/ir/irText/firProblems/functionLiteralGenericSignature.fir.kt.txt

@@ -0,0 +1,53 @@
+val unitFun: Function0<Unit>
+  field = local fun <anonymous>() {
+    return Unit
+  }
+
+  get
+
+val intFun: Function0<Int>
+  field = local fun <anonymous>(): Int {
+    return 42
+  }
+
+  get
+
+val stringParamFun: Function1<String, Unit>
+  field = local fun <anonymous>(x: String) {
+    return Unit
+  }
+
+  get
+
+val listFun: Function1<List<String>, List<String>>
+  field = local fun <anonymous>(l: List<String>): List<String> {
+    return l
+  }
+
+  get
+
+val mutableListFun: Function1<MutableList<Double>, MutableList<Int>>
+  field = local fun <no name provided>(l: MutableList<Double>): MutableList<Int> {
+    return CHECK_NOT_NULL<Nothing>(arg0 = null)
+  }
+
+  get
+
+val funWithIn: Function1<Comparable<String>, Unit>
+  field = local fun <no name provided>(x: Comparable<String>) {
+  }
+
+  get
+
+val extensionFun: @ExtensionFunctionType Function1<Any, Unit>
+  field = local fun Any.<no name provided>() {
+  }
+
+  get
+
+val extensionWithArgFun: @ExtensionFunctionType Function2<Long, Any, Date>
+  field = local fun Long.<no name provided>(x: Any): Date {
+    return Date()
+  }
+
+  get

compiler/testData/ir/irText/firProblems/functionLiteralGenericSignature.ir.txt

@@ -0,0 +1,110 @@
+FILE fqName:<root> fileName:/functionLiteralGenericSignature.kt
+  PROPERTY name:unitFun visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:unitFun type:kotlin.Function0<kotlin.Unit> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=kotlin.Function0<kotlin.Unit> origin=LAMBDA
+          FUN LOCAL_FUNCTION_FOR_LAMBDA name:<anonymous> visibility:local modality:FINAL <> () returnType:kotlin.Unit
+            BLOCK_BODY
+              RETURN type=kotlin.Nothing from='local final fun <anonymous> (): kotlin.Unit declared in <root>.unitFun'
+                GET_OBJECT 'CLASS IR_EXTERNAL_DECLARATION_STUB OBJECT name:Unit modality:FINAL visibility:public superTypes:[kotlin.Any]' type=kotlin.Unit
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-unitFun> visibility:public modality:FINAL <> () returnType:kotlin.Function0<kotlin.Unit>
+      correspondingProperty: PROPERTY name:unitFun visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-unitFun> (): kotlin.Function0<kotlin.Unit> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:unitFun type:kotlin.Function0<kotlin.Unit> visibility:private [final,static]' type=kotlin.Function0<kotlin.Unit> origin=null
+  PROPERTY name:intFun visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:intFun type:kotlin.Function0<kotlin.Int> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=kotlin.Function0<kotlin.Int> origin=LAMBDA
+          FUN LOCAL_FUNCTION_FOR_LAMBDA name:<anonymous> visibility:local modality:FINAL <> () returnType:kotlin.Int
+            BLOCK_BODY
+              RETURN type=kotlin.Nothing from='local final fun <anonymous> (): kotlin.Int declared in <root>.intFun'
+                CONST Int type=kotlin.Int value=42
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-intFun> visibility:public modality:FINAL <> () returnType:kotlin.Function0<kotlin.Int>
+      correspondingProperty: PROPERTY name:intFun visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-intFun> (): kotlin.Function0<kotlin.Int> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:intFun type:kotlin.Function0<kotlin.Int> visibility:private [final,static]' type=kotlin.Function0<kotlin.Int> origin=null
+  PROPERTY name:stringParamFun visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:stringParamFun type:kotlin.Function1<kotlin.String, kotlin.Unit> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=kotlin.Function1<kotlin.String, kotlin.Unit> origin=LAMBDA
+          FUN LOCAL_FUNCTION_FOR_LAMBDA name:<anonymous> visibility:local modality:FINAL <> (x:kotlin.String) returnType:kotlin.Unit
+            VALUE_PARAMETER name:x index:0 type:kotlin.String
+            BLOCK_BODY
+              RETURN type=kotlin.Nothing from='local final fun <anonymous> (x: kotlin.String): kotlin.Unit declared in <root>.stringParamFun'
+                GET_OBJECT 'CLASS IR_EXTERNAL_DECLARATION_STUB OBJECT name:Unit modality:FINAL visibility:public superTypes:[kotlin.Any]' type=kotlin.Unit
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-stringParamFun> visibility:public modality:FINAL <> () returnType:kotlin.Function1<kotlin.String, kotlin.Unit>
+      correspondingProperty: PROPERTY name:stringParamFun visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-stringParamFun> (): kotlin.Function1<kotlin.String, kotlin.Unit> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:stringParamFun type:kotlin.Function1<kotlin.String, kotlin.Unit> visibility:private [final,static]' type=kotlin.Function1<kotlin.String, kotlin.Unit> origin=null
+  PROPERTY name:listFun visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:listFun type:kotlin.Function1<kotlin.collections.List<kotlin.String>, kotlin.collections.List<kotlin.String>> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=kotlin.Function1<kotlin.collections.List<kotlin.String>, kotlin.collections.List<kotlin.String>> origin=LAMBDA
+          FUN LOCAL_FUNCTION_FOR_LAMBDA name:<anonymous> visibility:local modality:FINAL <> (l:kotlin.collections.List<kotlin.String>) returnType:kotlin.collections.List<kotlin.String>
+            VALUE_PARAMETER name:l index:0 type:kotlin.collections.List<kotlin.String>
+            BLOCK_BODY
+              RETURN type=kotlin.Nothing from='local final fun <anonymous> (l: kotlin.collections.List<kotlin.String>): kotlin.collections.List<kotlin.String> declared in <root>.listFun'
+                GET_VAR 'l: kotlin.collections.List<kotlin.String> declared in <root>.listFun.<anonymous>' type=kotlin.collections.List<kotlin.String> origin=null
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-listFun> visibility:public modality:FINAL <> () returnType:kotlin.Function1<kotlin.collections.List<kotlin.String>, kotlin.collections.List<kotlin.String>>
+      correspondingProperty: PROPERTY name:listFun visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-listFun> (): kotlin.Function1<kotlin.collections.List<kotlin.String>, kotlin.collections.List<kotlin.String>> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:listFun type:kotlin.Function1<kotlin.collections.List<kotlin.String>, kotlin.collections.List<kotlin.String>> visibility:private [final,static]' type=kotlin.Function1<kotlin.collections.List<kotlin.String>, kotlin.collections.List<kotlin.String>> origin=null
+  PROPERTY name:mutableListFun visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:mutableListFun type:kotlin.Function1<kotlin.collections.MutableList<kotlin.Double>, kotlin.collections.MutableList<kotlin.Int>> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=kotlin.Function1<kotlin.collections.MutableList<kotlin.Double>, kotlin.collections.MutableList<kotlin.Int>> origin=ANONYMOUS_FUNCTION
+          FUN LOCAL_FUNCTION name:<no name provided> visibility:local modality:FINAL <> (l:kotlin.collections.MutableList<kotlin.Double>) returnType:kotlin.collections.MutableList<kotlin.Int>
+            VALUE_PARAMETER name:l index:0 type:kotlin.collections.MutableList<kotlin.Double>
+            BLOCK_BODY
+              RETURN type=kotlin.Nothing from='local final fun <no name provided> (l: kotlin.collections.MutableList<kotlin.Double>): kotlin.collections.MutableList<kotlin.Int> declared in <root>.mutableListFun'
+                CALL 'public final fun CHECK_NOT_NULL <T0> (arg0: T0 of kotlin.internal.ir.CHECK_NOT_NULL?): T0 of kotlin.internal.ir.CHECK_NOT_NULL declared in kotlin.internal.ir' type=kotlin.Nothing origin=EXCLEXCL
+                  <T0>: kotlin.Nothing
+                  arg0: CONST Null type=kotlin.Nothing? value=null
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-mutableListFun> visibility:public modality:FINAL <> () returnType:kotlin.Function1<kotlin.collections.MutableList<kotlin.Double>, kotlin.collections.MutableList<kotlin.Int>>
+      correspondingProperty: PROPERTY name:mutableListFun visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-mutableListFun> (): kotlin.Function1<kotlin.collections.MutableList<kotlin.Double>, kotlin.collections.MutableList<kotlin.Int>> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:mutableListFun type:kotlin.Function1<kotlin.collections.MutableList<kotlin.Double>, kotlin.collections.MutableList<kotlin.Int>> visibility:private [final,static]' type=kotlin.Function1<kotlin.collections.MutableList<kotlin.Double>, kotlin.collections.MutableList<kotlin.Int>> origin=null
+  PROPERTY name:funWithIn visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:funWithIn type:kotlin.Function1<kotlin.Comparable<kotlin.String>, kotlin.Unit> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=kotlin.Function1<kotlin.Comparable<kotlin.String>, kotlin.Unit> origin=ANONYMOUS_FUNCTION
+          FUN LOCAL_FUNCTION name:<no name provided> visibility:local modality:FINAL <> (x:kotlin.Comparable<kotlin.String>) returnType:kotlin.Unit
+            VALUE_PARAMETER name:x index:0 type:kotlin.Comparable<kotlin.String>
+            BLOCK_BODY
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-funWithIn> visibility:public modality:FINAL <> () returnType:kotlin.Function1<kotlin.Comparable<kotlin.String>, kotlin.Unit>
+      correspondingProperty: PROPERTY name:funWithIn visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-funWithIn> (): kotlin.Function1<kotlin.Comparable<kotlin.String>, kotlin.Unit> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:funWithIn type:kotlin.Function1<kotlin.Comparable<kotlin.String>, kotlin.Unit> visibility:private [final,static]' type=kotlin.Function1<kotlin.Comparable<kotlin.String>, kotlin.Unit> origin=null
+  PROPERTY name:extensionFun visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:extensionFun type:@[ExtensionFunctionType] kotlin.Function1<kotlin.Any, kotlin.Unit> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=@[ExtensionFunctionType] kotlin.Function1<kotlin.Any, kotlin.Unit> origin=ANONYMOUS_FUNCTION
+          FUN LOCAL_FUNCTION name:<no name provided> visibility:local modality:FINAL <> ($receiver:kotlin.Any) returnType:kotlin.Unit
+            $receiver: VALUE_PARAMETER name:<this> type:kotlin.Any
+            BLOCK_BODY
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-extensionFun> visibility:public modality:FINAL <> () returnType:@[ExtensionFunctionType] kotlin.Function1<kotlin.Any, kotlin.Unit>
+      correspondingProperty: PROPERTY name:extensionFun visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-extensionFun> (): @[ExtensionFunctionType] kotlin.Function1<kotlin.Any, kotlin.Unit> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:extensionFun type:@[ExtensionFunctionType] kotlin.Function1<kotlin.Any, kotlin.Unit> visibility:private [final,static]' type=@[ExtensionFunctionType] kotlin.Function1<kotlin.Any, kotlin.Unit> origin=null
+  PROPERTY name:extensionWithArgFun visibility:public modality:FINAL [val]
+    FIELD PROPERTY_BACKING_FIELD name:extensionWithArgFun type:@[ExtensionFunctionType] kotlin.Function2<kotlin.Long, kotlin.Any, java.util.Date> visibility:private [final,static]
+      EXPRESSION_BODY
+        FUN_EXPR type=@[ExtensionFunctionType] kotlin.Function2<kotlin.Long, kotlin.Any, java.util.Date> origin=ANONYMOUS_FUNCTION
+          FUN LOCAL_FUNCTION name:<no name provided> visibility:local modality:FINAL <> ($receiver:kotlin.Long, x:kotlin.Any) returnType:java.util.Date
+            $receiver: VALUE_PARAMETER name:<this> type:kotlin.Long
+            VALUE_PARAMETER name:x index:0 type:kotlin.Any
+            BLOCK_BODY
+              RETURN type=kotlin.Nothing from='local final fun <no name provided> (x: kotlin.Any): java.util.Date declared in <root>.extensionWithArgFun'
+                CONSTRUCTOR_CALL 'public constructor <init> () declared in java.util.Date' type=java.util.Date origin=null
+    FUN DEFAULT_PROPERTY_ACCESSOR name:<get-extensionWithArgFun> visibility:public modality:FINAL <> () returnType:@[ExtensionFunctionType] kotlin.Function2<kotlin.Long, kotlin.Any, java.util.Date>
+      correspondingProperty: PROPERTY name:extensionWithArgFun visibility:public modality:FINAL [val]
+      BLOCK_BODY
+        RETURN type=kotlin.Nothing from='public final fun <get-extensionWithArgFun> (): @[ExtensionFunctionType] kotlin.Function2<kotlin.Long, kotlin.Any, java.util.Date> declared in <root>'
+          GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:extensionWithArgFun type:@[ExtensionFunctionType] kotlin.Function2<kotlin.Long, kotlin.Any, java.util.Date> visibility:private [final,static]' type=@[ExtensionFunctionType] kotlin.Function2<kotlin.Long, kotlin.Any, java.util.Date> origin=null

compiler/testData/ir/irText/firProblems/functionLiteralGenericSignature.kt

@@ -0,0 +1,11 @@
+import java.util.Date
+
+val unitFun = { }
+val intFun = { 42 }
+val stringParamFun = { x: String -> }
+val listFun = { l: List<String> -> l }
+val mutableListFun = fun (l: MutableList<Double>): MutableList<Int> = null!!
+val funWithIn = fun (x: Comparable<String>) {}
+
+val extensionFun = fun Any.() {}
+val extensionWithArgFun = fun Long.(x: Any): Date = Date()

compiler/testData/ir/irText/firProblems/functionLiteralGenericSignature.kt.txt

@@ -0,0 +1,53 @@
+val unitFun: Function0<Unit>
+  field = local fun <anonymous>() {
+    return Unit
+  }
+
+  get
+
+val intFun: Function0<Int>
+  field = local fun <anonymous>(): Int {
+    return 42
+  }
+
+  get
+
+val stringParamFun: Function1<String, Unit>
+  field = local fun <anonymous>(x: String) {
+    return Unit
+  }
+
+  get
+
+val listFun: Function1<List<String>, List<String>>
+  field = local fun <anonymous>(l: List<String>): List<String> {
+    return l
+  }
+
+  get
+
+val mutableListFun: Function1<MutableList<Double>, MutableList<Int>>
+  field = local fun <no name provided>(l: MutableList<Double>): MutableList<Int> {
+    return CHECK_NOT_NULL<Nothing>(arg0 = null)
+  }
+
+  get
+
+val funWithIn: Function1<Comparable<String>, Unit>
+  field = local fun <no name provided>(x: Comparable<String>) {
+  }
+
+  get
+
+val extensionFun: @ExtensionFunctionType Function1<Any, Unit>
+  field = local fun Any.<no name provided>() {
+  }
+
+  get
+
+val extensionWithArgFun: @ExtensionFunctionType Function2<Long, Any, Date>
+  field = local fun Long.<no name provided>(x: Any): Date {
+    return Date()
+  }
+
+  get

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ir/IrTextTestGenerated.java

@@ -2494,6 +2494,12 @@ public class IrTextTestGenerated extends AbstractIrTextTest {
             runTest("compiler/testData/ir/irText/firProblems/FlushFromAnonymous.kt");
         }
 
+        @Test
+        @TestMetadata("functionLiteralGenericSignature.kt")
+        public void testFunctionLiteralGenericSignature() throws Exception {
+            runTest("compiler/testData/ir/irText/firProblems/functionLiteralGenericSignature.kt");
+        }
+
         @Test
         @TestMetadata("ImplicitReceiverStack.kt")
         public void testImplicitReceiverStack() throws Exception {

compiler/tests-gen/org/jetbrains/kotlin/klib/KlibTextTestCaseGenerated.java

@@ -1857,6 +1857,11 @@ public class KlibTextTestCaseGenerated extends AbstractKlibTextTestCase {
             runTest("compiler/testData/ir/irText/firProblems/FlushFromAnonymous.kt");
         }
 
+        @TestMetadata("functionLiteralGenericSignature.kt")
+        public void testFunctionLiteralGenericSignature() throws Exception {
+            runTest("compiler/testData/ir/irText/firProblems/functionLiteralGenericSignature.kt");
+        }
+
         @TestMetadata("ImplicitReceiverStack.kt")
         public void testImplicitReceiverStack() throws Exception {
             runTest("compiler/testData/ir/irText/firProblems/ImplicitReceiverStack.kt");