[NI] Support @OnlyInputTypes annotation. #KT-29307 fixed

compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/inference/model/MutableConstraintStorage.kt

@@ -8,9 +8,14 @@ package org.jetbrains.kotlin.resolve.calls.inference.model
 import org.jetbrains.kotlin.resolve.calls.inference.trimToSize
 import org.jetbrains.kotlin.resolve.calls.model.KotlinCallDiagnostic
 import org.jetbrains.kotlin.resolve.calls.tower.isSuccess
+import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.types.model.KotlinTypeMarker
 import org.jetbrains.kotlin.types.model.TypeConstructorMarker
 import org.jetbrains.kotlin.types.model.TypeVariableMarker
+import org.jetbrains.kotlin.types.TypeConstructor
+import org.jetbrains.kotlin.types.UnwrappedType
+import org.jetbrains.kotlin.types.checker.NewCapturedType
+import org.jetbrains.kotlin.types.typeUtil.unCapture
 import kotlin.collections.ArrayList
 import kotlin.collections.LinkedHashMap
 
@@ -27,6 +32,16 @@ class MutableVariableWithConstraints(
             return simplifiedConstraints!!
         }
 
+    // see @OnlyInputTypes annotation
+    val projectedInputCallTypes: Collection<UnwrappedType>
+        get() =
+            mutableConstraints.filter {
+                val position = it.position.from
+                position is ArgumentConstraintPosition || position is ReceiverConstraintPosition || position is ExpectedTypeConstraintPosition
+            }.map {
+                (it.type as KotlinType).unCapture().unwrap()
+            }
+
     private val mutableConstraints = ArrayList(constraints)
 
     private var simplifiedConstraints: List<Constraint>? = null

compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/inference/model/NewConstraintSystemImpl.kt

@@ -9,12 +9,16 @@ import org.jetbrains.kotlin.resolve.calls.components.PostponedArgumentsAnalyzer
 import org.jetbrains.kotlin.resolve.calls.inference.*
 import org.jetbrains.kotlin.resolve.calls.inference.components.ConstraintInjector
 import org.jetbrains.kotlin.resolve.calls.inference.components.KotlinConstraintSystemCompleter
-import org.jetbrains.kotlin.resolve.calls.inference.components.NewTypeSubstitutor
 import org.jetbrains.kotlin.resolve.calls.inference.components.ResultTypeResolver
 import org.jetbrains.kotlin.resolve.calls.model.KotlinCallDiagnostic
+import org.jetbrains.kotlin.resolve.calls.model.OnlyInputTypesDiagnostic
+import org.jetbrains.kotlin.types.IntersectionTypeConstructor
+import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.types.checker.NewCapturedType
+import org.jetbrains.kotlin.types.checker.NewKotlinTypeChecker
 import org.jetbrains.kotlin.types.model.*
 import org.jetbrains.kotlin.utils.SmartList
+import org.jetbrains.kotlin.utils.addToStdlib.safeAs
 import kotlin.math.max
 
 class NewConstraintSystemImpl(
@@ -247,7 +251,8 @@ class NewConstraintSystemImpl(
         checkState(State.BUILDING, State.COMPLETION)
 
         constraintInjector.addInitialEqualityConstraint(this, variable.defaultType(), resultType, FixVariableConstraintPosition(variable))
-        notFixedTypeVariables.remove(variable.freshTypeConstructor())
+        val variableWithConstraints = notFixedTypeVariables.remove(variable.freshTypeConstructor())
+        checkOnlyInputTypesAnnotation(variableWithConstraints, resultType)
 
         for (variableWithConstraint in notFixedTypeVariables.values) {
             variableWithConstraint.removeConstrains {
@@ -258,6 +263,25 @@ class NewConstraintSystemImpl(
         storage.fixedTypeVariables[variable.freshTypeConstructor()] = resultType
     }
 
+    private fun checkOnlyInputTypesAnnotation(
+        variableWithConstraints: MutableVariableWithConstraints?,
+        resultType: KotlinTypeMarker
+    ) {
+        if (resultType !is KotlinType) return
+        if (variableWithConstraints == null || variableWithConstraints.typeVariable.safeAs<NewTypeVariable>()?.hasOnlyInputTypesAnnotation() != true ) return
+        val projectedInputCallTypes = variableWithConstraints.projectedInputCallTypes
+        val resultTypeIsInputType = projectedInputCallTypes.any { inputType ->
+            val constructor = inputType.constructor
+            if (constructor is IntersectionTypeConstructor)
+                constructor.supertypes.any { NewKotlinTypeChecker.equalTypes(resultType, it) }
+            else
+                NewKotlinTypeChecker.equalTypes(resultType, inputType)
+        }
+        if (!resultTypeIsInputType) {
+            addError(OnlyInputTypesDiagnostic(variableWithConstraints.typeVariable as NewTypeVariable))
+        }
+    }
+
     // KotlinConstraintSystemCompleter.Context, PostponedArgumentsAnalyzer.Context
     override fun canBeProper(type: KotlinTypeMarker): Boolean {
         checkState(State.BUILDING, State.COMPLETION)

compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/inference/model/TypeVariable.kt

@@ -22,6 +22,7 @@ import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
 import org.jetbrains.kotlin.descriptors.annotations.Annotations
 import org.jetbrains.kotlin.resolve.calls.model.LambdaKotlinCallArgument
 import org.jetbrains.kotlin.resolve.descriptorUtil.builtIns
+import org.jetbrains.kotlin.resolve.descriptorUtil.hasOnlyInputTypesAnnotation
 import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.types.KotlinTypeFactory
 import org.jetbrains.kotlin.types.SimpleType
@@ -53,15 +54,21 @@ sealed class NewTypeVariable(builtIns: KotlinBuiltIns, name: String) : TypeVaria
         nullable = false, memberScope = builtIns.any.unsubstitutedMemberScope
     )
 
+    abstract fun hasOnlyInputTypesAnnotation(): Boolean
+
     override fun toString() = freshTypeConstructor.toString()
 }
 
 class TypeVariableFromCallableDescriptor(
     val originalTypeParameter: TypeParameterDescriptor
-) : NewTypeVariable(originalTypeParameter.builtIns, originalTypeParameter.name.identifier)
+) : NewTypeVariable(originalTypeParameter.builtIns, originalTypeParameter.name.identifier) {
+    override fun hasOnlyInputTypesAnnotation(): Boolean = originalTypeParameter.hasOnlyInputTypesAnnotation()
+}
 
 class TypeVariableForLambdaReturnType(
     val lambdaArgument: LambdaKotlinCallArgument,
     builtIns: KotlinBuiltIns,
     name: String
-) : NewTypeVariable(builtIns, name)
+) : NewTypeVariable(builtIns, name) {
+    override fun hasOnlyInputTypesAnnotation(): Boolean = false
+}

compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/model/KotlinCallDiagnostics.kt

@@ -20,6 +20,7 @@ import org.jetbrains.kotlin.descriptors.CallableDescriptor
 import org.jetbrains.kotlin.descriptors.CallableMemberDescriptor
 import org.jetbrains.kotlin.descriptors.ValueParameterDescriptor
 import org.jetbrains.kotlin.resolve.calls.components.CallableReferenceCandidate
+import org.jetbrains.kotlin.resolve.calls.inference.model.NewTypeVariable
 import org.jetbrains.kotlin.resolve.calls.tower.ResolutionCandidateApplicability.*
 import org.jetbrains.kotlin.types.TypeConstructor
 import org.jetbrains.kotlin.types.UnwrappedType
@@ -195,4 +196,10 @@ class ArgumentTypeMismatchDiagnostic(
     override fun report(reporter: DiagnosticReporter) {
         reporter.onCallArgument(expressionArgument, this)
     }
+}
+
+class OnlyInputTypesDiagnostic(val typeVariable: NewTypeVariable) : KotlinCallDiagnostic(INAPPLICABLE) {
+    override fun report(reporter: DiagnosticReporter) {
+        reporter.onCall(this)
+    }
 }