[FIR] Replace uninferred type variables and stub types during delegate inference

compiler/fir/providers/src/org/jetbrains/kotlin/fir/resolve/substitution/Substitutors.kt

@@ -6,6 +6,8 @@
 package org.jetbrains.kotlin.fir.resolve.substitution
 
 import org.jetbrains.kotlin.fir.FirSession
+import org.jetbrains.kotlin.fir.diagnostics.ConeSimpleDiagnostic
+import org.jetbrains.kotlin.fir.diagnostics.DiagnosticKind
 import org.jetbrains.kotlin.fir.resolve.fullyExpandedType
 import org.jetbrains.kotlin.fir.resolve.toFirRegularClassSymbol
 import org.jetbrains.kotlin.fir.resolve.withCombinedAttributesFrom
@@ -19,6 +21,7 @@ import org.jetbrains.kotlin.types.model.TypeConstructorMarker
 import org.jetbrains.kotlin.types.model.TypeSubstitutorMarker
 import org.jetbrains.kotlin.types.model.TypeVariableMarker
 import org.jetbrains.kotlin.types.model.typeConstructor
+import org.jetbrains.kotlin.utils.addToStdlib.runIf
 
 abstract class AbstractConeSubstitutor(protected val typeContext: ConeTypeContext) : ConeSubstitutor() {
     protected fun wrapProjection(old: ConeTypeProjection, newType: ConeKotlinType): ConeTypeProjection {
@@ -285,12 +288,12 @@ fun createTypeSubstitutorByTypeConstructor(
 
 internal class ConeTypeSubstitutorByTypeConstructor(
     private val map: Map<TypeConstructorMarker, ConeKotlinType>,
-    private val context: ConeTypeContext,
+    typeContext: ConeTypeContext,
     private val approximateIntegerLiterals: Boolean
-) : AbstractConeSubstitutor(context), TypeSubstitutorMarker {
+) : AbstractConeSubstitutor(typeContext), TypeSubstitutorMarker {
     override fun substituteType(type: ConeKotlinType): ConeKotlinType? {
         if (type !is ConeLookupTagBasedType && type !is ConeStubType) return null
-        val new = map[type.typeConstructor(context)] ?: return null
+        val new = map[type.typeConstructor(typeContext)] ?: return null
         val approximatedIntegerLiteralType = if (approximateIntegerLiterals) new.approximateIntegerLiteralType() else new
         return approximatedIntegerLiteralType.updateNullabilityIfNeeded(type)?.withCombinedAttributesFrom(type)
     }
@@ -308,3 +311,33 @@ class NotFixedTypeToVariableSubstitutorForDelegateInference(
     }
 }
 
+class ConeStubAndTypeVariableToErrorTypeSubstitutor(
+    typeContext: ConeTypeContext,
+    private val stubTypesToReplace: Collection<ConeStubTypeConstructor>
+) : AbstractConeSubstitutor(typeContext) {
+    override fun substituteType(type: ConeKotlinType): ConeKotlinType? {
+        return when (type) {
+            is ConeTypeVariableType -> ConeErrorType(
+                ConeSimpleDiagnostic("Type for ${type.lookupTag.debugName} is not inferred", DiagnosticKind.InferenceError),
+                isUninferredParameter = true
+            )
+            is ConeStubType -> runIf(type.constructor in stubTypesToReplace) {
+                ConeErrorType(
+                    ConeSimpleDiagnostic(
+                        "Type for stub of ${type.constructor.variable.typeConstructor.debugName} is not inferred",
+                        DiagnosticKind.InferenceError
+                    ),
+                    isUninferredParameter = true
+                )
+            }
+            else -> null
+        }
+    }
+}
+
+fun ConeSubstitutor.replaceStubsAndTypeVariablesToErrors(
+    typeContext: ConeTypeContext,
+    stubTypesToReplace: Collection<ConeStubTypeConstructor>
+): ConeSubstitutor {
+    return ChainedSubstitutor(this, ConeStubAndTypeVariableToErrorTypeSubstitutor(typeContext, stubTypesToReplace))
+}

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/inference/FirDelegatedPropertyInferenceSession.kt

@@ -10,9 +10,7 @@ import org.jetbrains.kotlin.fir.expressions.FirResolvable
 import org.jetbrains.kotlin.fir.expressions.FirStatement
 import org.jetbrains.kotlin.fir.resolve.calls.*
 import org.jetbrains.kotlin.fir.resolve.inference.model.ConeFixVariableConstraintPosition
-import org.jetbrains.kotlin.fir.resolve.substitution.ChainedSubstitutor
+import org.jetbrains.kotlin.fir.resolve.substitution.*
-import org.jetbrains.kotlin.fir.resolve.substitution.ConeSubstitutor
-import org.jetbrains.kotlin.fir.resolve.substitution.NotFixedTypeToVariableSubstitutorForDelegateInference
 import org.jetbrains.kotlin.fir.types.*
 import org.jetbrains.kotlin.resolve.calls.inference.ConstraintSystemBuilder
 import org.jetbrains.kotlin.resolve.calls.inference.NewConstraintSystem
@@ -228,9 +226,11 @@ class FirDelegatedPropertyInferenceSession(
     fun createFinalSubstitutor(): ConeSubstitutor {
         val stubTypeSubstitutor = createNonFixedTypeToVariableSubstitutor()
 
+        val typeContext = components.session.typeContext
         val resultSubstitutor = resultingConstraintSystem.asReadOnlyStorage()
-            .buildAbstractResultingSubstitutor(components.session.typeContext) as ConeSubstitutor
+            .buildAbstractResultingSubstitutor(typeContext) as ConeSubstitutor
         return ChainedSubstitutor(stubTypeSubstitutor, resultSubstitutor)
+            .replaceStubsAndTypeVariablesToErrors(typeContext, stubTypesByTypeVariable.values.map { it.constructor })
     }
 
     val stubTypesByTypeVariable: MutableMap<ConeTypeVariable, ConeStubType> = mutableMapOf()

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

@@ -265,7 +265,6 @@ open class FirDeclarationsResolveTransformer(transformer: FirBodyResolveTransfor
     }
 
     private fun transformPropertyAccessorsWithDelegate(property: FirProperty) {
-
         context.forPropertyDelegateAccessors(property, resolutionContext, callCompleter) {
             // Resolve delegate expression, after that, delegate will contain either expr.provideDelegate or expr
             if (property.isLocal) {
@@ -282,7 +281,6 @@ open class FirDeclarationsResolveTransformer(transformer: FirBodyResolveTransfor
 
             val finalSubstitutor = createFinalSubstitutor()
 
-            // Replace stub types with corresponding type variable types
             val stubTypeCompletionResultsWriter = FirStubTypeTransformer(finalSubstitutor)
             property.transformSingle(stubTypeCompletionResultsWriter, null)
 

compiler/testData/diagnostics/tests/delegation/kt44843.fir.kt

@@ -1,13 +1,13 @@
 // WITH_STDLIB
 
 // FILE: test.kt
-val bar2 by <!DELEGATE_SPECIAL_FUNCTION_AMBIGUITY, NO_VALUE_FOR_PARAMETER!>bar2()<!>
+val bar2 by <!NO_VALUE_FOR_PARAMETER!>bar2()<!>
 
 // FILE: lt/neworld/compiler/Foo.kt
 package lt.neworld.compiler
 
 class Foo {
-    val bar by <!DELEGATE_SPECIAL_FUNCTION_AMBIGUITY, NO_VALUE_FOR_PARAMETER!>bar()<!>
+    val bar by <!NO_VALUE_FOR_PARAMETER!>bar()<!>
 }
 
 // FILE: lt/neworld/compiler/bar/Bar.kt

compiler/testData/diagnostics/tests/delegation/kt49477.fir.kt

@@ -8,7 +8,7 @@ inline fun <reified Self : DatabaseEntity, reified Target : DatabaseEntity> Self
     property: KProperty1<Target, MutableCollection<Self>>): Delegate<Self, Target?> = TODO()
 
 class GitLabBuildProcessor: DatabaseEntity {
-    var processor by <!NEW_INFERENCE_NO_INFORMATION_FOR_PARAMETER!>parent<!>(GitLabChangesProcessor::buildProcessors)
+    var processor by parent(GitLabChangesProcessor::buildProcessors)
 }
 
 interface DatabaseEntity: Entity

compiler/testData/diagnostics/tests/delegation/kt49477Error.fir.kt

@@ -9,7 +9,7 @@ inline fun <reified Self : DatabaseEntity, reified Target : DatabaseEntity> Self
     property: KProperty1<Target, MutableCollection<Self>>): Delegate<Self, Target?> = TODO()
 
 class GitLabBuildProcessor: DatabaseEntity {
-    var processor by <!NEW_INFERENCE_NO_INFORMATION_FOR_PARAMETER!>parent<!>(GitLabChangesProcessor::buildProcessors)
+    var processor by parent(GitLabChangesProcessor::buildProcessors)
 }
 
 interface DatabaseEntity: Entity

compiler/testData/diagnostics/tests/inference/builderInference/stubTypes/stubTypeReceiverRestriction.fir.kt

@@ -69,4 +69,4 @@ fun test6() {
         genericLambda { it.extension() }
         use(::extension)
     }
-}
+}

compiler/testData/diagnostics/tests/inference/builderInference/stubTypes/stubTypeReceiverRestrictionDisabled.fir.kt

@@ -70,4 +70,4 @@ fun test6() {
         genericLambda { it.extension() }
         use(::extension)
     }
-}
+}

compiler/testData/diagnostics/testsWithStdLib/inference/delegates/kt50994.fir.kt

@@ -1,10 +1,11 @@
+// FIR_DUMP
 // WITH_REFLECT
 
 import kotlin.properties.ReadWriteProperty
 import kotlin.reflect.KProperty1
 
 class ProcessorWithParent : Entity {
-    var processor by <!NEW_INFERENCE_NO_INFORMATION_FOR_PARAMETER!>parent<!>(ProcessorWithChildren::processors)
+    var processor by parent(ProcessorWithChildren::processors)
 }
 
 class ProcessorWithChildren : Entity {

compiler/testData/diagnostics/testsWithStdLib/inference/delegates/kt50994.fir.txt

@@ -0,0 +1,95 @@
+FILE: kt50994.fir.kt
+    public final class ProcessorWithParent : R|Entity| {
+        public constructor(): R|ProcessorWithParent| {
+            super<R|kotlin/Any|>()
+        }
+
+        public final var processor: R|ProcessorWithChildren?|by this@R|/ProcessorWithParent|.R|/parent|<R|ProcessorWithParent|, R|ProcessorWithChildren|>(Q|ProcessorWithChildren|::R|/ProcessorWithChildren.processors|)
+            public get(): R|ProcessorWithChildren?| {
+                ^ this@R|/ProcessorWithParent|.D|/ProcessorWithParent.processor|.R|SubstitutionOverride</Delegate.getValue: R|Stub (chain inference): TypeVariable(_TP)?|>|(this@R|/ProcessorWithParent|, ::R|/ProcessorWithParent.processor|)
+            }
+            public set(<set-?>: R|ProcessorWithChildren?|): R|kotlin/Unit| {
+                this@R|/ProcessorWithParent|.D|/ProcessorWithParent.processor|.R|SubstitutionOverride</Delegate.setValue: R|kotlin/Unit|>|(this@R|/ProcessorWithParent|, ::R|/ProcessorWithParent.processor|, R|<local>/processor|)
+            }
+
+    }
+    public final class ProcessorWithChildren : R|Entity| {
+        public constructor(): R|ProcessorWithChildren| {
+            super<R|kotlin/Any|>()
+        }
+
+        public final var processors: R|kotlin/collections/MutableCollection<ERROR CLASS: Type for TC is not inferred>|by this@R|/ProcessorWithChildren|.<Inapplicable(INAPPLICABLE): /children>#<R|ERROR CLASS: Type for SC is not inferred|, R|ERROR CLASS: Type for TC is not inferred|>(<getClass>(Q|ProcessorWithParent|).R|kotlin/jvm/java|<R|ProcessorWithParent|>, Q|ProcessorWithParent|::<Unresolved reference: processor>#)
+            public get(): R|kotlin/collections/MutableCollection<ERROR CLASS: Type for TC is not inferred>| {
+                ^ this@R|/ProcessorWithChildren|.D|/ProcessorWithChildren.processors|.R|SubstitutionOverride</Delegate.getValue: R|kotlin/collections/MutableCollection<Stub (chain inference): TypeVariable(_TC)>|>|(this@R|/ProcessorWithChildren|, ::R|/ProcessorWithChildren.processors|)
+            }
+            public set(<set-?>: R|kotlin/collections/MutableCollection<ERROR CLASS: Type for TC is not inferred>|): R|kotlin/Unit| {
+                this@R|/ProcessorWithChildren|.D|/ProcessorWithChildren.processors|.R|SubstitutionOverride</Delegate.setValue: R|kotlin/Unit|>|(this@R|/ProcessorWithChildren|, ::R|/ProcessorWithChildren.processors|, R|<local>/processors|)
+            }
+
+    }
+    public final class Processor2WithParent : R|Entity| {
+        public constructor(): R|Processor2WithParent| {
+            super<R|kotlin/Any|>()
+        }
+
+        public final var processor: R|Processor2WithChildren?|by this@R|/Processor2WithParent|.R|/parent|<R|Processor2WithParent|, R|Processor2WithChildren|>(Q|Processor2WithChildren|::R|/Processor2WithChildren.processors|)
+            public get(): R|Processor2WithChildren?| {
+                ^ this@R|/Processor2WithParent|.D|/Processor2WithParent.processor|.R|SubstitutionOverride</Delegate.getValue: R|Processor2WithChildren?|>|(this@R|/Processor2WithParent|, ::R|/Processor2WithParent.processor|)
+            }
+            public set(<set-?>: R|Processor2WithChildren?|): R|kotlin/Unit| {
+                this@R|/Processor2WithParent|.D|/Processor2WithParent.processor|.R|SubstitutionOverride</Delegate.setValue: R|kotlin/Unit|>|(this@R|/Processor2WithParent|, ::R|/Processor2WithParent.processor|, R|<local>/processor|)
+            }
+
+    }
+    public final class Processor2WithChildren : R|Entity| {
+        public constructor(): R|Processor2WithChildren| {
+            super<R|kotlin/Any|>()
+        }
+
+        public final var processors: R|kotlin/collections/MutableCollection<Processor2WithParent>|by this@R|/Processor2WithChildren|.R|/children|<R|Processor2WithChildren|, R|Processor2WithParent|>(<getClass>(Q|Processor2WithParent|).R|kotlin/jvm/java|<R|Processor2WithParent|>, Q|Processor2WithParent|::R|/Processor2WithParent.processor|)
+            public get(): R|kotlin/collections/MutableCollection<Processor2WithParent>| {
+                ^ this@R|/Processor2WithChildren|.D|/Processor2WithChildren.processors|.R|SubstitutionOverride</Delegate.getValue: R|kotlin/collections/MutableCollection<Stub (chain inference): TypeVariable(_TC)>|>|(this@R|/Processor2WithChildren|, ::R|/Processor2WithChildren.processors|)
+            }
+            public set(<set-?>: R|kotlin/collections/MutableCollection<Processor2WithParent>|): R|kotlin/Unit| {
+                this@R|/Processor2WithChildren|.D|/Processor2WithChildren.processors|.R|SubstitutionOverride</Delegate.setValue: R|kotlin/Unit|>|(this@R|/Processor2WithChildren|, ::R|/Processor2WithChildren.processors|, R|<local>/processors|)
+            }
+
+    }
+    public final class Processor3WithParent : R|Entity| {
+        public constructor(): R|Processor3WithParent| {
+            super<R|kotlin/Any|>()
+        }
+
+        public final var processor: R|Processor3WithChildren?|by this@R|/Processor3WithParent|.R|/parent|<R|Processor3WithParent|, R|Processor3WithChildren|>(Q|Processor3WithChildren|::R|/Processor3WithChildren.processors|)
+            public get(): R|Processor3WithChildren?| {
+                ^ this@R|/Processor3WithParent|.D|/Processor3WithParent.processor|.R|SubstitutionOverride</Delegate.getValue: R|Processor3WithChildren?|>|(this@R|/Processor3WithParent|, ::R|/Processor3WithParent.processor|)
+            }
+            public set(<set-?>: R|Processor3WithChildren?|): R|kotlin/Unit| {
+                this@R|/Processor3WithParent|.D|/Processor3WithParent.processor|.R|SubstitutionOverride</Delegate.setValue: R|kotlin/Unit|>|(this@R|/Processor3WithParent|, ::R|/Processor3WithParent.processor|, R|<local>/processor|)
+            }
+
+    }
+    public final class Processor3WithChildren : R|Entity| {
+        public constructor(): R|Processor3WithChildren| {
+            super<R|kotlin/Any|>()
+        }
+
+        public final var processors: R|kotlin/collections/MutableCollection<Processor3WithParent>|by this@R|/Processor3WithChildren|.R|/children|<R|Processor3WithChildren|, R|Processor3WithParent|>(<getClass>(Q|Processor3WithParent|).R|kotlin/jvm/java|<R|Processor3WithParent|>, Q|Processor3WithParent|::R|/Processor3WithParent.processor|)
+            public get(): R|kotlin/collections/MutableCollection<Processor3WithParent>| {
+                ^ this@R|/Processor3WithChildren|.D|/Processor3WithChildren.processors|.R|SubstitutionOverride</Delegate.getValue: R|kotlin/collections/MutableCollection<Stub (chain inference): TypeVariable(_TC)>|>|(this@R|/Processor3WithChildren|, ::R|/Processor3WithChildren.processors|)
+            }
+            public set(<set-?>: R|kotlin/collections/MutableCollection<Processor3WithParent>|): R|kotlin/Unit| {
+                this@R|/Processor3WithChildren|.D|/Processor3WithChildren.processors|.R|SubstitutionOverride</Delegate.setValue: R|kotlin/Unit|>|(this@R|/Processor3WithChildren|, ::R|/Processor3WithChildren.processors|, R|<local>/processors|)
+            }
+
+    }
+    public final inline fun <reified SP : R|Entity|, reified TP : R|Entity|> R|SP|.parent(property: R|kotlin/reflect/KProperty1<TP, kotlin/collections/MutableCollection<SP>>|): R|Delegate<SP, TP?>| {
+        ^parent Null(null)!!
+    }
+    public final fun <SC : R|Entity|, TC : R|Entity|> R|SC|.children(clazz: R|java/lang/Class<TC>|, property: R|kotlin/reflect/KProperty1<TC, SC?>|, name: R|kotlin/String| = R|<local>/property|.R|SubstitutionOverride<kotlin/reflect/KProperty1.name: R|kotlin/String|>|): R|Delegate<SC, kotlin/collections/MutableCollection<TC>>| {
+        ^children Null(null)!!
+    }
+    public abstract interface Delegate<R : R|Entity|, T> : R|kotlin/properties/ReadWriteProperty<R, T>| {
+    }
+    public abstract interface Entity : R|kotlin/Any| {
+    }

compiler/testData/diagnostics/testsWithStdLib/inference/delegates/kt50994.kt

@@ -1,3 +1,4 @@
+// FIR_DUMP
 // WITH_REFLECT
 
 import kotlin.properties.ReadWriteProperty