Allow use reference to reified type parameters in contracts since 1.4

compiler/fir/resolve/tests/org/jetbrains/kotlin/fir/FirOldFrontendDiagnosticsTestWithStdlibGenerated.java

@@ -1385,6 +1385,11 @@ public class FirOldFrontendDiagnosticsTestWithStdlibGenerated extends AbstractFi
                 runTest("compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/receiver.kt");
             }
 
+            @TestMetadata("reifiedGeneric.kt")
+            public void testReifiedGeneric() throws Exception {
+                runTest("compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/reifiedGeneric.kt");
+            }
+
             @TestMetadata("safecallAndReturnsNull.kt")
             public void testSafecallAndReturnsNull() throws Exception {
                 runTest("compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/safecallAndReturnsNull.kt");

compiler/frontend/src/org/jetbrains/kotlin/contracts/EffectsExtractingVisitor.kt

@@ -20,10 +20,7 @@ import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.config.LanguageFeature
 import org.jetbrains.kotlin.config.LanguageVersionSettings
 import org.jetbrains.kotlin.contracts.description.ContractProviderKey
-import org.jetbrains.kotlin.contracts.model.Computation
+import org.jetbrains.kotlin.contracts.model.*
-import org.jetbrains.kotlin.contracts.model.ConditionalEffect
-import org.jetbrains.kotlin.contracts.model.ESEffect
-import org.jetbrains.kotlin.contracts.model.Functor
 import org.jetbrains.kotlin.contracts.model.functors.*
 import org.jetbrains.kotlin.contracts.model.structure.*
 import org.jetbrains.kotlin.contracts.model.visitors.Reducer
@@ -71,12 +68,13 @@ class EffectsExtractingVisitor(
         if (resolvedCall.isCallWithUnsupportedReceiver()) return UNKNOWN_COMPUTATION
 
         val arguments = resolvedCall.getCallArgumentsAsComputations() ?: return UNKNOWN_COMPUTATION
+        val typeSubstitution = resolvedCall.getTypeSubstitution()
 
         val descriptor = resolvedCall.resultingDescriptor
         return when {
             descriptor.isEqualsDescriptor() -> CallComputation(
                 ESBooleanType,
-                EqualsFunctor(false).invokeWithArguments(arguments, reducer)
+                EqualsFunctor(false).invokeWithArguments(arguments, typeSubstitution, reducer)
             )
             descriptor is ValueDescriptor -> ESVariableWithDataFlowValue(
                 descriptor,
@@ -86,7 +84,7 @@ class EffectsExtractingVisitor(
                 val esType = descriptor.returnType?.toESType()
                 CallComputation(
                     esType,
-                    descriptor.getFunctor()?.invokeWithArguments(arguments, reducer) ?: emptyList()
+                    descriptor.getFunctor()?.invokeWithArguments(arguments, typeSubstitution, reducer) ?: emptyList()
                 )
             }
             else -> UNKNOWN_COMPUTATION
@@ -123,7 +121,7 @@ class EffectsExtractingVisitor(
         val arg = extractOrGetCached(expression.leftHandSide)
         return CallComputation(
             ESBooleanType,
-            IsFunctor(rightType, expression.isNegated).invokeWithArguments(listOf(arg), reducer)
+            IsFunctor(rightType, expression.isNegated).invokeWithArguments(listOf(arg), emptyMap(), reducer)
         )
     }
 
@@ -148,10 +146,10 @@ class EffectsExtractingVisitor(
         val args = listOf(left, right)
 
         return when (expression.operationToken) {
-            KtTokens.EXCLEQ -> CallComputation(ESBooleanType, EqualsFunctor(true).invokeWithArguments(args, reducer))
+            KtTokens.EXCLEQ -> CallComputation(ESBooleanType, EqualsFunctor(true).invokeWithArguments(args, emptyMap(), reducer))
-            KtTokens.EQEQ -> CallComputation(ESBooleanType, EqualsFunctor(false).invokeWithArguments(args, reducer))
+            KtTokens.EQEQ -> CallComputation(ESBooleanType, EqualsFunctor(false).invokeWithArguments(args, emptyMap(), reducer))
-            KtTokens.ANDAND -> CallComputation(ESBooleanType, AndFunctor().invokeWithArguments(args, reducer))
+            KtTokens.ANDAND -> CallComputation(ESBooleanType, AndFunctor().invokeWithArguments(args, emptyMap(), reducer))
-            KtTokens.OROR -> CallComputation(ESBooleanType, OrFunctor().invokeWithArguments(args, reducer))
+            KtTokens.OROR -> CallComputation(ESBooleanType, OrFunctor().invokeWithArguments(args, emptyMap(), reducer))
             else -> UNKNOWN_COMPUTATION
         }
     }
@@ -215,6 +213,14 @@ class EffectsExtractingVisitor(
         return arguments
     }
 
+    private fun ResolvedCall<*>.getTypeSubstitution(): ESTypeSubstitution {
+        val result = mutableMapOf<ESKotlinType, ESKotlinType>()
+        for ((typeParameter, typeArgument) in typeArguments) {
+            result[ESKotlinType(typeParameter.defaultType)] = ESKotlinType(typeArgument)
+        }
+        return result
+    }
+
     private fun ResolvedValueArgument.toComputation(): Computation? {
         return when (this) {
             // Assume that we don't know anything about default arguments

compiler/frontend/src/org/jetbrains/kotlin/contracts/parsing/ContractParsingServices.kt

@@ -16,14 +16,14 @@
 
 package org.jetbrains.kotlin.contracts.parsing
 
-import org.jetbrains.kotlin.config.AnalysisFlags
 import org.jetbrains.kotlin.config.LanguageFeature
 import org.jetbrains.kotlin.config.LanguageVersionSettings
 import org.jetbrains.kotlin.contracts.description.ContractDescription
 import org.jetbrains.kotlin.contracts.description.ContractProviderKey
 import org.jetbrains.kotlin.contracts.description.LazyContractProvider
-import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
-import org.jetbrains.kotlin.psi.*
+import org.jetbrains.kotlin.descriptors.FunctionDescriptor
+import org.jetbrains.kotlin.psi.KtExpression
 import org.jetbrains.kotlin.psi.psiUtil.isContractDescriptionCallPsiCheck
 import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.BindingTrace
@@ -46,7 +46,7 @@ class ContractParsingServices(val languageVersionSettings: LanguageVersionSettin
         // is a *necessary* (but not sufficient, actually) condition for presence of 'LazyContractProvider'
         if (!expression.isContractDescriptionCallPsiCheck()) return
 
-        val callContext = ContractCallContext(expression, scope, trace)
+        val callContext = ContractCallContext(expression, scope, trace, languageVersionSettings)
         val contractProviderIfAny =
             (scope.ownerDescriptor as? FunctionDescriptor)?.getUserData(ContractProviderKey) as? LazyContractProvider?
         var resultingContractDescription: ContractDescription? = null
@@ -104,7 +104,8 @@ class ContractParsingServices(val languageVersionSettings: LanguageVersionSettin
 class ContractCallContext(
     val contractCallExpression: KtExpression,
     val scope: LexicalScope,
-    val trace: BindingTrace
+    val trace: BindingTrace,
+    val languageVersionSettings: LanguageVersionSettings
 ) {
     val ownerDescriptor: DeclarationDescriptor = scope.ownerDescriptor
     val functionDescriptor: FunctionDescriptor = ownerDescriptor as FunctionDescriptor

compiler/frontend/src/org/jetbrains/kotlin/contracts/parsing/PsiConditionParser.kt

@@ -16,7 +16,8 @@
 
 package org.jetbrains.kotlin.contracts.parsing
 
-import org.jetbrains.kotlin.contracts.description.*
+import org.jetbrains.kotlin.config.LanguageFeature
+import org.jetbrains.kotlin.contracts.description.BooleanExpression
 import org.jetbrains.kotlin.contracts.description.expressions.*
 import org.jetbrains.kotlin.descriptors.ValueDescriptor
 import org.jetbrains.kotlin.descriptors.impl.AbstractTypeParameterDescriptor
@@ -47,8 +48,16 @@ internal class PsiConditionParser(
         }
 
         if (descriptor is AbstractTypeParameterDescriptor) {
-            collector.badDescription("references to type parameters are forbidden in contracts", typeReference)
+            val reifiedGenericsAllowed = callContext.languageVersionSettings.supportsFeature(LanguageFeature.AllowReifiedGenericsInContracts)
-            return null
+            if (!reifiedGenericsAllowed || !descriptor.isReified) {
+                val message = if (reifiedGenericsAllowed) {
+                    "references to not reified type parameters are forbidden in contracts"
+                } else {
+                    "references to type parameters are forbidden in contracts"
+                }
+                collector.badDescription(message, typeReference)
+                return null
+            }
         }
 
         // This should be reported as "Can't check for erased" error, but we explicitly abort contract parsing. Just in case.

compiler/resolution/src/org/jetbrains/kotlin/contracts/model/Functor.kt

@@ -16,6 +16,7 @@
 
 package org.jetbrains.kotlin.contracts.model
 
+import org.jetbrains.kotlin.contracts.model.structure.ESKotlinType
 import org.jetbrains.kotlin.contracts.model.visitors.Reducer
 
 /**
@@ -27,13 +28,19 @@ import org.jetbrains.kotlin.contracts.model.visitors.Reducer
  * values, it takes effects and returns effects.
  */
 interface Functor {
-    fun invokeWithArguments(arguments: List<Computation>, reducer: Reducer): List<ESEffect>
+    fun invokeWithArguments(arguments: List<Computation>, typeSubstitution: ESTypeSubstitution, reducer: Reducer): List<ESEffect>
 }
 
 
 abstract class AbstractFunctor : Functor {
-    override fun invokeWithArguments(arguments: List<Computation>, reducer: Reducer): List<ESEffect> =
+    override fun invokeWithArguments(arguments: List<Computation>, typeSubstitution: ESTypeSubstitution, reducer: Reducer): List<ESEffect> =
-        reducer.reduceEffects(doInvocation(arguments, reducer))
+        reducer.reduceEffects(doInvocation(arguments, typeSubstitution, reducer))
 
-    protected abstract fun doInvocation(arguments: List<Computation>, reducer: Reducer): List<ESEffect>
+    protected abstract fun doInvocation(
-}
+        arguments: List<Computation>,
+        typeSubstitution: ESTypeSubstitution,
+        reducer: Reducer
+    ): List<ESEffect>
+}
+
+typealias ESTypeSubstitution = Map<ESKotlinType, ESKotlinType>

compiler/resolution/src/org/jetbrains/kotlin/contracts/model/functors/AbstractBinaryFunctor.kt

@@ -17,11 +17,14 @@
 package org.jetbrains.kotlin.contracts.model.functors
 
 import org.jetbrains.kotlin.contracts.model.*
-import org.jetbrains.kotlin.contracts.model.structure.*
+import org.jetbrains.kotlin.contracts.model.structure.ESConstant
+import org.jetbrains.kotlin.contracts.model.structure.ESOr
+import org.jetbrains.kotlin.contracts.model.structure.isReturns
+import org.jetbrains.kotlin.contracts.model.structure.isWildcard
 import org.jetbrains.kotlin.contracts.model.visitors.Reducer
 
 abstract class AbstractBinaryFunctor : AbstractFunctor() {
-    override fun doInvocation(arguments: List<Computation>, reducer: Reducer): List<ESEffect> {
+    override fun doInvocation(arguments: List<Computation>, typeSubstitution: ESTypeSubstitution, reducer: Reducer): List<ESEffect> {
         assert(arguments.size == 2) { "Wrong size of arguments list for Binary functor: expected 2, got ${arguments.size}" }
         return invokeWithArguments(arguments[0], arguments[1])
     }

compiler/resolution/src/org/jetbrains/kotlin/contracts/model/functors/AbstractUnaryFunctor.kt

@@ -29,7 +29,7 @@ import org.jetbrains.kotlin.contracts.model.visitors.Reducer
  * be called only on clauses that haven't failed before reaching functor transformation.
  */
 abstract class AbstractUnaryFunctor : AbstractFunctor() {
-    override fun doInvocation(arguments: List<Computation>, reducer: Reducer): List<ESEffect> {
+    override fun doInvocation(arguments: List<Computation>, typeSubstitution: ESTypeSubstitution, reducer: Reducer): List<ESEffect> {
         assert(arguments.size == 1) { "Wrong size of arguments list for Unary operator: expected 1, got ${arguments.size}" }
         return invokeWithArguments(arguments[0])
     }

compiler/resolution/src/org/jetbrains/kotlin/contracts/model/functors/EqualsFunctor.kt

@@ -38,7 +38,7 @@ class EqualsFunctor(val isNegated: Boolean) : AbstractFunctor() {
         We don't want to code here fair analysis for general cases, because it's too complex. Instead, we just
         check some specific cases, which are useful enough in practice
      */
-    override fun doInvocation(arguments: List<Computation>, reducer: Reducer): List<ESEffect> {
+    override fun doInvocation(arguments: List<Computation>, typeSubstitution: ESTypeSubstitution, reducer: Reducer): List<ESEffect> {
         assert(arguments.size == 2) { "Equals functor expected 2 arguments, got ${arguments.size}" }
 
         // TODO: AnnotationConstructorCaller kills this with implicit receiver. Investigate, how.

compiler/resolution/src/org/jetbrains/kotlin/contracts/model/functors/IsFunctor.kt

@@ -24,21 +24,23 @@ import org.jetbrains.kotlin.contracts.model.structure.ESType
 import org.jetbrains.kotlin.contracts.model.visitors.Reducer
 
 class IsFunctor(val type: ESType, val isNegated: Boolean) : AbstractFunctor() {
-    override fun doInvocation(arguments: List<Computation>, reducer: Reducer): List<ESEffect> {
+    override fun doInvocation(arguments: List<Computation>, typeSubstitution: ESTypeSubstitution, reducer: Reducer): List<ESEffect> {
         assert(arguments.size == 1) { "Wrong size of arguments list for Unary operator: expected 1, got ${arguments.size}" }
-        return invokeWithArguments(arguments[0])
+        return invokeWithArguments(arguments[0], typeSubstitution)
     }
 
-    fun invokeWithArguments(arg: Computation): List<ESEffect> {
+    fun invokeWithArguments(arg: Computation, typeSubstitution: ESTypeSubstitution): List<ESEffect> {
         return if (arg is ESValue)
-            invokeWithValue(arg)
+            invokeWithValue(arg, typeSubstitution)
         else
             emptyList()
     }
 
-    private fun invokeWithValue(value: ESValue): List<ConditionalEffect> {
+    private fun invokeWithValue(value: ESValue, typeSubstitution: ESTypeSubstitution): List<ConditionalEffect> {
-        val trueIs = ESIs(value, this)
+        val substitutedType = typeSubstitution[type] ?: type
-        val falseIs = ESIs(value, IsFunctor(type, isNegated.not()))
+
+        val trueIs = ESIs(value, IsFunctor(substitutedType, isNegated))
+        val falseIs = ESIs(value, IsFunctor(substitutedType, isNegated.not()))
 
         val trueResult = ConditionalEffect(trueIs, ESReturns(ESConstants.trueValue))
         val falseResult = ConditionalEffect(falseIs, ESReturns(ESConstants.falseValue))

compiler/resolution/src/org/jetbrains/kotlin/contracts/model/functors/SubstitutingFunctor.kt

@@ -28,7 +28,7 @@ class SubstitutingFunctor(
     private val basicEffects: List<ESEffect>,
     private val ownerFunction: FunctionDescriptor
 ) : AbstractFunctor() {
-    override fun doInvocation(arguments: List<Computation>, reducer: Reducer): List<ESEffect> {
+    override fun doInvocation(arguments: List<Computation>, typeSubstitution: ESTypeSubstitution, reducer: Reducer): List<ESEffect> {
         if (basicEffects.isEmpty()) return emptyList()
 
         val receiver =
@@ -40,7 +40,7 @@ class SubstitutingFunctor(
         }
 
         val substitutions = parameters.zip(arguments).toMap()
-        val substitutor = Substitutor(substitutions, reducer)
+        val substitutor = Substitutor(substitutions, typeSubstitution, reducer)
         val substitutedClauses = mutableListOf<ESEffect>()
 
         effectsLoop@ for (effect in basicEffects) {

compiler/resolution/src/org/jetbrains/kotlin/contracts/model/structure/Types.kt

@@ -36,6 +36,20 @@ object ESBooleanType : ESType() {
 
 class ESKotlinType(val type: KotlinType) : ESType() {
     override fun toKotlinType(builtIns: KotlinBuiltIns): KotlinType = type
+    override fun equals(other: Any?): Boolean {
+        if (this === other) return true
+        if (javaClass != other?.javaClass) return false
+
+        other as ESKotlinType
+
+        if (type != other.type) return false
+
+        return true
+    }
+
+    override fun hashCode(): Int {
+        return type.hashCode()
+    }
 }
 
 

compiler/resolution/src/org/jetbrains/kotlin/contracts/model/visitors/Substitutor.kt

@@ -19,6 +19,7 @@ package org.jetbrains.kotlin.contracts.model.visitors
 import org.jetbrains.kotlin.contracts.model.Computation
 import org.jetbrains.kotlin.contracts.model.ESExpression
 import org.jetbrains.kotlin.contracts.model.ESExpressionVisitor
+import org.jetbrains.kotlin.contracts.model.ESTypeSubstitution
 import org.jetbrains.kotlin.contracts.model.structure.*
 
 /**
@@ -28,11 +29,12 @@ import org.jetbrains.kotlin.contracts.model.structure.*
  */
 class Substitutor(
     private val substitutions: Map<ESVariable, Computation>,
+    private val typeSubstitution: ESTypeSubstitution,
     private val reducer: Reducer
 ) : ESExpressionVisitor<Computation?> {
     override fun visitIs(isOperator: ESIs): Computation? {
         val arg = isOperator.left.accept(this) ?: return null
-        return CallComputation(ESBooleanType, isOperator.functor.invokeWithArguments(arg))
+        return CallComputation(ESBooleanType, isOperator.functor.invokeWithArguments(arg, typeSubstitution))
     }
 
     override fun visitNot(not: ESNot): Computation? {
@@ -43,7 +45,7 @@ class Substitutor(
     override fun visitEqual(equal: ESEqual): Computation? {
         val left = equal.left.accept(this) ?: return null
         val right = equal.right.accept(this) ?: return null
-        return CallComputation(ESBooleanType, equal.functor.invokeWithArguments(listOf(left, right), reducer))
+        return CallComputation(ESBooleanType, equal.functor.invokeWithArguments(listOf(left, right), typeSubstitution, reducer))
     }
 
     override fun visitAnd(and: ESAnd): Computation? {

compiler/testData/diagnostics/testsWithStdLib/contracts/dsl/errors/contractCallSites.1.4.fir.kt

@@ -1,4 +1,4 @@
-// !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect +AllowContractsForNonOverridableMembers
+// !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect +AllowContractsForNonOverridableMembers +AllowReifiedGenericsInContracts
 // !USE_EXPERIMENTAL: kotlin.contracts.ExperimentalContracts
 // !DIAGNOSTICS: -INVISIBLE_REFERENCE -INVISIBLE_MEMBER -NOTHING_TO_INLINE -ABSTRACT_FUNCTION_IN_NON_ABSTRACT_CLASS -ABSTRACT_FUNCTION_WITH_BODY -UNUSED_PARAMETER -UNUSED_VARIABLE -EXPERIMENTAL_FEATURE_WARNING
 

compiler/testData/diagnostics/testsWithStdLib/contracts/dsl/errors/contractCallSites.1.4.kt

@@ -1,4 +1,4 @@
-// !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect +AllowContractsForNonOverridableMembers
+// !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect +AllowContractsForNonOverridableMembers +AllowReifiedGenericsInContracts
 // !USE_EXPERIMENTAL: kotlin.contracts.ExperimentalContracts
 // !DIAGNOSTICS: -INVISIBLE_REFERENCE -INVISIBLE_MEMBER -NOTHING_TO_INLINE -ABSTRACT_FUNCTION_IN_NON_ABSTRACT_CLASS -ABSTRACT_FUNCTION_WITH_BODY -UNUSED_PARAMETER -UNUSED_VARIABLE -EXPERIMENTAL_FEATURE_WARNING
 

compiler/testData/diagnostics/testsWithStdLib/contracts/dsl/errors/contractCallSites.1.4.txt

@@ -21,9 +21,15 @@ public open class Class {
     public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
     public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
     public final inline fun inlineMember(/*0*/ x: kotlin.Boolean): kotlin.Unit
+        Returns(WILDCARD) -> x
+
     public final fun member(/*0*/ x: kotlin.Boolean): kotlin.Unit
+        Returns(WILDCARD) -> x
+
     public open fun openMemeber(/*0*/ x: kotlin.Boolean): kotlin.Unit
     public final suspend fun suspendMember(/*0*/ x: kotlin.Boolean): kotlin.Unit
+        Returns(WILDCARD) -> x
+
     public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
 }
 

compiler/testData/diagnostics/testsWithStdLib/contracts/dsl/errors/typeReferences.1.3.fir.kt

@@ -1,4 +1,4 @@
-// !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect -AllowContractsForNonOverridableMembers
+// !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect -AllowContractsForNonOverridableMembers -AllowReifiedGenericsInContracts
 // !USE_EXPERIMENTAL: kotlin.contracts.ExperimentalContracts
 // !DIAGNOSTICS: -INVISIBLE_REFERENCE -INVISIBLE_MEMBER
 

compiler/testData/diagnostics/testsWithStdLib/contracts/dsl/errors/typeReferences.1.3.kt

@@ -1,4 +1,4 @@
-// !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect -AllowContractsForNonOverridableMembers
+// !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect -AllowContractsForNonOverridableMembers -AllowReifiedGenericsInContracts
 // !USE_EXPERIMENTAL: kotlin.contracts.ExperimentalContracts
 // !DIAGNOSTICS: -INVISIBLE_REFERENCE -INVISIBLE_MEMBER
 

compiler/testData/diagnostics/testsWithStdLib/contracts/dsl/errors/typeReferences.1.4.fir.kt

@@ -1,4 +1,4 @@
-// !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect +AllowContractsForNonOverridableMembers
+// !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect +AllowContractsForNonOverridableMembers +AllowReifiedGenericsInContracts
 // !USE_EXPERIMENTAL: kotlin.contracts.ExperimentalContracts
 // !DIAGNOSTICS: -INVISIBLE_REFERENCE -INVISIBLE_MEMBER
 

compiler/testData/diagnostics/testsWithStdLib/contracts/dsl/errors/typeReferences.1.4.kt

@@ -1,4 +1,4 @@
-// !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect +AllowContractsForNonOverridableMembers
+// !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect +AllowContractsForNonOverridableMembers +AllowReifiedGenericsInContracts
 // !USE_EXPERIMENTAL: kotlin.contracts.ExperimentalContracts
 // !DIAGNOSTICS: -INVISIBLE_REFERENCE -INVISIBLE_MEMBER
 
@@ -6,7 +6,7 @@ import kotlin.contracts.*
 
 inline fun <reified T> referToReifiedGeneric(x: Any?) {
     contract {
-        returns() implies (x is <!ERROR_IN_CONTRACT_DESCRIPTION("references to type parameters are forbidden in contracts")!>T<!>)
+        returns() implies (x is T)
     }
 }
 

compiler/testData/diagnostics/testsWithStdLib/contracts/dsl/errors/typeReferences.1.4.txt

@@ -6,6 +6,8 @@ public fun referToAliasedSimpleType(/*0*/ x: kotlin.Any?): kotlin.Unit
     Returns(WILDCARD) -> x is Int
 
 public inline fun </*0*/ reified T> referToReifiedGeneric(/*0*/ x: kotlin.Any?): kotlin.Unit
+    Returns(WILDCARD) -> x is T
+
 public fun referToSubstituted(/*0*/ x: kotlin.Any?): kotlin.Unit
 public fun referToSubstitutedWithStar(/*0*/ x: kotlin.Any?): kotlin.Unit
     Returns(WILDCARD) -> x is Generic<*>

compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/reifiedGeneric.fir.kt

@@ -0,0 +1,31 @@
+// !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect +AllowReifiedGenericsInContracts
+// !USE_EXPERIMENTAL: kotlin.contracts.ExperimentalContracts
+// !DIAGNOSTICS: -INVISIBLE_REFERENCE -INVISIBLE_MEMBER -UNUSED_VARIABLE
+
+import kotlin.contracts.*
+
+inline fun <reified T> requireIsInstance(value: Any?) {
+    contract {
+        returns() implies (value is T)
+    }
+    if (value !is T) {
+        throw IllegalArgumentException()
+    }
+}
+
+inline fun <reified T> cast(value: Any?): T {
+    contract {
+        returns() implies (value is T)
+    }
+    return value as T
+}
+
+fun test_1(x: Any) {
+    requireIsInstance<String>(x)
+    x.<!UNRESOLVED_REFERENCE!>length<!>
+}
+
+fun test_2(x: Any) {
+    val s: String = cast(x)
+    x.<!UNRESOLVED_REFERENCE!>length<!>
+}

compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/reifiedGeneric.kt

@@ -0,0 +1,31 @@
+// !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect +AllowReifiedGenericsInContracts
+// !USE_EXPERIMENTAL: kotlin.contracts.ExperimentalContracts
+// !DIAGNOSTICS: -INVISIBLE_REFERENCE -INVISIBLE_MEMBER -UNUSED_VARIABLE
+
+import kotlin.contracts.*
+
+inline fun <reified T> requireIsInstance(value: Any?) {
+    contract {
+        returns() implies (value is T)
+    }
+    if (value !is T) {
+        throw IllegalArgumentException()
+    }
+}
+
+inline fun <reified T> cast(value: Any?): T {
+    contract {
+        returns() implies (value is T)
+    }
+    return value as T
+}
+
+fun test_1(x: Any) {
+    requireIsInstance<String>(x)
+    <!DEBUG_INFO_SMARTCAST!>x<!>.length
+}
+
+fun test_2(x: Any) {
+    val s: String = cast(x)
+    <!DEBUG_INFO_SMARTCAST!>x<!>.length
+}

compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/reifiedGeneric.txt

@@ -0,0 +1,10 @@
+package
+
+public inline fun </*0*/ reified T> cast(/*0*/ value: kotlin.Any?): T
+    Returns(WILDCARD) -> value is T
+
+public inline fun </*0*/ reified T> requireIsInstance(/*0*/ value: kotlin.Any?): kotlin.Unit
+    Returns(WILDCARD) -> value is T
+
+public fun test_1(/*0*/ x: kotlin.Any): kotlin.Unit
+public fun test_2(/*0*/ x: kotlin.Any): kotlin.Unit

compiler/testData/loadJava/compiledKotlinWithStdlib/contracts/contractWithRefiedGeneric.kt

@@ -0,0 +1,23 @@
+// !LANGUAGE: +AllowContractsForCustomFunctions +ReadDeserializedContracts +AllowContractsForNonOverridableMembers +AllowReifiedGenericsInContracts
+// !USE_EXPERIMENTAL: kotlin.contracts.ExperimentalContracts
+@file:Suppress("INVISIBLE_MEMBER", "INVISIBLE_REFERENCE")
+
+package test
+
+import kotlin.contracts.*
+
+inline fun <reified T> requireIsInstance(value: Any?) {
+    contract {
+        returns() implies (value is T)
+    }
+    if (value !is T) {
+        throw IllegalArgumentException()
+    }
+}
+
+inline fun <reified T, reified U> cast(value: Any?, z: U): T {
+    contract {
+        returns() implies (value is T)
+    }
+    return value as T
+}

compiler/testData/loadJava/compiledKotlinWithStdlib/contracts/contractWithRefiedGeneric.txt

@@ -0,0 +1,7 @@
+package test
+
+public inline fun </*0*/ reified T, /*1*/ reified U> cast(/*0*/ value: kotlin.Any?, /*1*/ z: U): T
+    Returns(WILDCARD) -> value is T
+
+public inline fun </*0*/ reified T> requireIsInstance(/*0*/ value: kotlin.Any?): kotlin.Unit
+    Returns(WILDCARD) -> value is T

compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestWithStdLibGenerated.java

@@ -1386,6 +1386,11 @@ public class DiagnosticsTestWithStdLibGenerated extends AbstractDiagnosticsTestW
                 runTest("compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/receiver.kt");
             }
 
+            @TestMetadata("reifiedGeneric.kt")
+            public void testReifiedGeneric() throws Exception {
+                runTest("compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/reifiedGeneric.kt");
+            }
+
             @TestMetadata("safecallAndReturnsNull.kt")
             public void testSafecallAndReturnsNull() throws Exception {
                 runTest("compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/safecallAndReturnsNull.kt");

compiler/tests/org/jetbrains/kotlin/checkers/javac/DiagnosticsTestWithStdLibUsingJavacGenerated.java

@@ -1386,6 +1386,11 @@ public class DiagnosticsTestWithStdLibUsingJavacGenerated extends AbstractDiagno
                 runTest("compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/receiver.kt");
             }
 
+            @TestMetadata("reifiedGeneric.kt")
+            public void testReifiedGeneric() throws Exception {
+                runTest("compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/reifiedGeneric.kt");
+            }
+
             @TestMetadata("safecallAndReturnsNull.kt")
             public void testSafecallAndReturnsNull() throws Exception {
                 runTest("compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/safecallAndReturnsNull.kt");

compiler/tests/org/jetbrains/kotlin/jvm/compiler/LoadJavaTestGenerated.java

@@ -4650,6 +4650,11 @@ public class LoadJavaTestGenerated extends AbstractLoadJavaTest {
                 runTest("compiler/testData/loadJava/compiledKotlinWithStdlib/contracts/callsEffect.kt");
             }
 
+            @TestMetadata("contractWithRefiedGeneric.kt")
+            public void testContractWithRefiedGeneric() throws Exception {
+                runTest("compiler/testData/loadJava/compiledKotlinWithStdlib/contracts/contractWithRefiedGeneric.kt");
+            }
+
             @TestMetadata("contractsOnMembers.kt")
             public void testContractsOnMembers() throws Exception {
                 runTest("compiler/testData/loadJava/compiledKotlinWithStdlib/contracts/contractsOnMembers.kt");

compiler/tests/org/jetbrains/kotlin/jvm/compiler/ir/IrLoadJavaTestGenerated.java

@@ -4651,6 +4651,11 @@ public class IrLoadJavaTestGenerated extends AbstractIrLoadJavaTest {
                 runTest("compiler/testData/loadJava/compiledKotlinWithStdlib/contracts/callsEffect.kt");
             }
 
+            @TestMetadata("contractWithRefiedGeneric.kt")
+            public void testContractWithRefiedGeneric() throws Exception {
+                runTest("compiler/testData/loadJava/compiledKotlinWithStdlib/contracts/contractWithRefiedGeneric.kt");
+            }
+
             @TestMetadata("contractsOnMembers.kt")
             public void testContractsOnMembers() throws Exception {
                 runTest("compiler/testData/loadJava/compiledKotlinWithStdlib/contracts/contractsOnMembers.kt");

compiler/tests/org/jetbrains/kotlin/jvm/compiler/javac/LoadJavaUsingJavacTestGenerated.java

@@ -4650,6 +4650,11 @@ public class LoadJavaUsingJavacTestGenerated extends AbstractLoadJavaUsingJavacT
                 runTest("compiler/testData/loadJava/compiledKotlinWithStdlib/contracts/callsEffect.kt");
             }
 
+            @TestMetadata("contractWithRefiedGeneric.kt")
+            public void testContractWithRefiedGeneric() throws Exception {
+                runTest("compiler/testData/loadJava/compiledKotlinWithStdlib/contracts/contractWithRefiedGeneric.kt");
+            }
+
             @TestMetadata("contractsOnMembers.kt")
             public void testContractsOnMembers() throws Exception {
                 runTest("compiler/testData/loadJava/compiledKotlinWithStdlib/contracts/contractsOnMembers.kt");

compiler/util/src/org/jetbrains/kotlin/config/LanguageVersionSettings.kt

@@ -122,6 +122,7 @@ enum class LanguageFeature(
     AllowResultInReturnType(KOTLIN_1_4),
     PreferJavaFieldOverload(KOTLIN_1_4),
     AllowContractsForNonOverridableMembers(KOTLIN_1_4),
+    AllowReifiedGenericsInContracts(KOTLIN_1_4),
 
     ProperVisibilityForCompanionObjectInstanceField(sinceVersion = null, kind = BUG_FIX),
     // Temporarily disabled, see KT-27084/KT-22379

core/deserialization/src/org/jetbrains/kotlin/serialization/deserialization/MemberDeserializer.kt

@@ -296,7 +296,7 @@ class MemberDeserializer(private val c: DeserializationContext) {
         function.isExpect = Flags.IS_EXPECT_FUNCTION.get(flags)
 
         val mapValueForContract =
-            c.components.contractDeserializer.deserializeContractFromFunction(proto, function, c.typeTable, c.typeDeserializer)
+            c.components.contractDeserializer.deserializeContractFromFunction(proto, function, c.typeTable, local.typeDeserializer)
         if (mapValueForContract != null) {
             function.putInUserDataMap(mapValueForContract.first, mapValueForContract.second)
         }