[FIR] UPPER_BOUND_CANNOT_BE_ARRAY diagnostic

compiler/fir/checkers/checkers-component-generator/src/org/jetbrains/kotlin/fir/checkers/generator/diagnostics/FirJvmDiagnosticsList.kt

@@ -29,6 +29,10 @@ object JVM_DIAGNOSTICS_LIST : DiagnosticList("FirJvmErrors") {
         }
     }
 
+    val TYPE_PARAMETERS by object : DiagnosticGroup("Type parameters") {
+        val UPPER_BOUND_CANNOT_BE_ARRAY by error<PsiElement>()
+    }
+
     val ANNOTATIONS by object : DiagnosticGroup("annotations") {
         val STRICTFP_ON_CLASS by error<KtAnnotationEntry>()
         val VOLATILE_ON_VALUE by error<KtAnnotationEntry>()

compiler/fir/checkers/checkers.jvm/gen/org/jetbrains/kotlin/fir/analysis/diagnostics/jvm/FirJvmErrors.kt

@@ -25,6 +25,9 @@ object FirJvmErrors {
     // Types
     val JAVA_TYPE_MISMATCH by error2<KtExpression, ConeKotlinType, ConeKotlinType>()
 
+    // Type parameters
+    val UPPER_BOUND_CANNOT_BE_ARRAY by error0<PsiElement>()
+
     // annotations
     val STRICTFP_ON_CLASS by error0<KtAnnotationEntry>()
     val VOLATILE_ON_VALUE by error0<KtAnnotationEntry>()

compiler/fir/checkers/checkers.jvm/src/org/jetbrains/kotlin/fir/analysis/jvm/checkers/JvmDeclarationCheckers.kt

@@ -16,7 +16,7 @@ object JvmDeclarationCheckers : DeclarationCheckers() {
 
     override val classCheckers: Set<FirClassChecker>
         get() = setOf(
-            FirStrictfpApplicabilityChecker
+            FirStrictfpApplicabilityChecker,
         )
 
     override val propertyCheckers: Set<FirPropertyChecker>
@@ -29,4 +29,9 @@ object JvmDeclarationCheckers : DeclarationCheckers() {
             FirSynchronizedAnnotationChecker,
             FirOverloadsChecker,
         )
+
+    override val typeParameterCheckers: Set<FirTypeParameterChecker>
+        get() = setOf(
+            FirUpperBoundsChecker,
+        )
 }

compiler/fir/checkers/checkers.jvm/src/org/jetbrains/kotlin/fir/analysis/jvm/checkers/declaration/FirUpperBoundsChecker.kt

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.fir.analysis.jvm.checkers.declaration
+
+import org.jetbrains.kotlin.fir.analysis.checkers.context.CheckerContext
+import org.jetbrains.kotlin.fir.analysis.checkers.declaration.FirTypeParameterChecker
+import org.jetbrains.kotlin.fir.analysis.diagnostics.DiagnosticReporter
+import org.jetbrains.kotlin.fir.analysis.diagnostics.jvm.FirJvmErrors
+import org.jetbrains.kotlin.fir.analysis.diagnostics.reportOn
+import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
+import org.jetbrains.kotlin.fir.types.coneType
+import org.jetbrains.kotlin.fir.types.isArrayType
+
+object FirUpperBoundsChecker : FirTypeParameterChecker() {
+
+    override fun check(declaration: FirTypeParameter, context: CheckerContext, reporter: DiagnosticReporter) {
+        if (declaration.bounds.any { it.coneType.isArrayType }) {
+            reporter.reportOn(declaration.source, FirJvmErrors.UPPER_BOUND_CANNOT_BE_ARRAY, context)
+        }
+    }
+
+}

compiler/testData/diagnostics/tests/typeParameters/upperBoundCannotBeArray.fir.kt

@@ -1,18 +0,0 @@
-fun <A : Array<Any>> f1() {}
-fun <T, A : Array<out T>> f2() {}
-fun <S, T : S, A> f3() where A : Array<out S>, A : <!REPEATED_BOUND!>Array<out T><!> {}
-
-fun <T : <!FINAL_UPPER_BOUND!>IntArray<!>> f4() {}
-
-fun <T> f5() where T : Array<Any> {}
-
-val <T : Array<Any?>> T.v: String get() = ""
-
-class C2<T, A : Array<out T>>
-interface C3<S, T : S, A> where A : Array<out S>, A : <!REPEATED_BOUND!>Array<out T><!>
-
-fun foo() {
-    class C1<A : Array<Any>> {
-        fun <A : Array<Any>, B : Array<Any>, C : A> f() {}
-    }
-}

compiler/testData/diagnostics/tests/typeParameters/upperBoundCannotBeArray.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 fun <<!UPPER_BOUND_CANNOT_BE_ARRAY!>A : Array<Any><!>> f1() {}
 fun <T, <!UPPER_BOUND_CANNOT_BE_ARRAY!>A : Array<out T><!>> f2() {}
 fun <S, T : S, <!UPPER_BOUND_CANNOT_BE_ARRAY!>A<!>> f3() where A : Array<out S>, A : <!REPEATED_BOUND!>Array<out T><!> {}

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/frontend/api/fir/diagnostics/KtFirDataClassConverters.kt

@@ -3447,6 +3447,12 @@ internal val KT_DIAGNOSTIC_CONVERTER = KtDiagnosticConverterBuilder.buildConvert
             token,
         )
     }
+    add(FirJvmErrors.UPPER_BOUND_CANNOT_BE_ARRAY) { firDiagnostic ->
+        UpperBoundCannotBeArrayImpl(
+            firDiagnostic as FirPsiDiagnostic,
+            token,
+        )
+    }
     add(FirJvmErrors.STRICTFP_ON_CLASS) { firDiagnostic ->
         StrictfpOnClassImpl(
             firDiagnostic as FirPsiDiagnostic,

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/frontend/api/fir/diagnostics/KtFirDiagnostics.kt

@@ -2404,6 +2404,10 @@ sealed class KtFirDiagnostic<PSI : PsiElement> : KtDiagnosticWithPsi<PSI> {
         abstract val actualType: KtType
     }
 
+    abstract class UpperBoundCannotBeArray : KtFirDiagnostic<PsiElement>() {
+        override val diagnosticClass get() = UpperBoundCannotBeArray::class
+    }
+
     abstract class StrictfpOnClass : KtFirDiagnostic<KtAnnotationEntry>() {
         override val diagnosticClass get() = StrictfpOnClass::class
     }

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/frontend/api/fir/diagnostics/KtFirDiagnosticsImpl.kt

@@ -3887,6 +3887,13 @@ internal class JavaTypeMismatchImpl(
     override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
 }
 
+internal class UpperBoundCannotBeArrayImpl(
+    firDiagnostic: FirPsiDiagnostic,
+    override val token: ValidityToken,
+) : KtFirDiagnostic.UpperBoundCannotBeArray(), KtAbstractFirDiagnostic<PsiElement> {
+    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
+}
+
 internal class StrictfpOnClassImpl(
     firDiagnostic: FirPsiDiagnostic,
     override val token: ValidityToken,