[Frontend, Ir] Equality test passes

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/ConversionUtils.kt

@@ -621,7 +621,7 @@ fun Fir2IrComponents.createTemporaryVariableForSafeCallConstruction(
 
 // TODO: implement inlineClassRepresentation in FirRegularClass instead.
 fun Fir2IrComponents.computeInlineClassRepresentation(klass: FirRegularClass): InlineClassRepresentation<IrSimpleType>? {
-    if (!klass.isInline) return null
+    if (!(klass.isInline && klass.primaryConstructorIfAny(session)?.valueParameterSymbols?.size == 1)) return null
     val parameter = klass.getInlineClassUnderlyingParameter(session) ?: error("Inline class has no underlying parameter: ${klass.render()}")
     val underlyingType = parameter.returnTypeRef.toIrType(typeConverter)
     return InlineClassRepresentation(

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrClassifierStorage.kt

@@ -26,7 +26,10 @@ import org.jetbrains.kotlin.ir.builders.declarations.UNDEFINED_PARAMETER_INDEX
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.declarations.impl.IrExternalPackageFragmentImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrEnumConstructorCallImpl
-import org.jetbrains.kotlin.ir.symbols.*
+import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
+import org.jetbrains.kotlin.ir.symbols.IrEnumEntrySymbol
+import org.jetbrains.kotlin.ir.symbols.IrTypeAliasSymbol
+import org.jetbrains.kotlin.ir.symbols.IrTypeParameterSymbol
 import org.jetbrains.kotlin.ir.symbols.impl.*
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.types.impl.IrSimpleTypeImpl
@@ -284,7 +287,7 @@ class Fir2IrClassifierStorage(
                     isInner = regularClass.isInner,
                     isData = regularClass.isData,
                     isExternal = regularClass.isExternal,
-                    isInline = regularClass.isInline,
+                    isInline = regularClass.isInline && regularClass.primaryConstructorIfAny(session)?.valueParameterSymbols?.size == 1,
                     isExpect = regularClass.isExpect,
                     isFun = regularClass.isFun
                 ).apply {

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/lazy/Fir2IrLazyClass.kt

@@ -11,6 +11,7 @@ import org.jetbrains.kotlin.fir.backend.*
 import org.jetbrains.kotlin.fir.declarations.FirDeclarationOrigin
 import org.jetbrains.kotlin.fir.declarations.FirRegularClass
 import org.jetbrains.kotlin.fir.declarations.FirSimpleFunction
+import org.jetbrains.kotlin.fir.declarations.primaryConstructorIfAny
 import org.jetbrains.kotlin.fir.declarations.utils.*
 import org.jetbrains.kotlin.fir.dispatchReceiverClassOrNull
 import org.jetbrains.kotlin.fir.isNewPlaceForBodyGeneration
@@ -94,7 +95,7 @@ class Fir2IrLazyClass(
         get() = fir.isExternal
 
     override val isInline: Boolean
-        get() = fir.isInline
+        get() = fir.isInline && fir.primaryConstructorIfAny(session)?.valueParameterSymbols?.size == 1
 
     override val isExpect: Boolean
         get() = fir.isExpect

compiler/testData/codegen/box/valueClasses/equality.kt

@@ -159,15 +159,15 @@ fun box(): String {
     assert(b.toString() == b.toString())
     assert(b.hashCode() == b.hashCode())
 
-    assert(f1.toString() == "to be replaced")
-    assert(f2.toString() == "to be replaced")
-    assert(f3.toString() == "to be replaced")
-    assert(f4.toString() == "to be replaced")
-    assert(f5.toString() == "to be replaced")
-    assert(f6.toString() == "to be replaced")
-    assert(a1.toString() == "to be replaced")
-    assert(a2.toString() == "to be replaced")
-    assert(b.toString() == "to be replaced")
+    assert(f1.toString() == "F1(x=1)") { f1.toString() }
+    assert(f2.toString() == "F2(x=4294967295)") { f2.toString() }
+    assert(f3.toString().startsWith("F3@")) { f3.toString() } // not data class yet
+    assert(f4.toString() == "F4(x=5)") { f4.toString() }
+    assert(f5.toString() == "F5(x=4294967294)") { f5.toString() }
+    assert(f6.toString() == "F6(x=678)") { f6.toString() }
+    assert(a1.toString().startsWith("A@")) { a1.toString() } // not data class yet
+    assert(a2.toString().startsWith("A@")) { a2.toString() } // not data class yet
+    assert(b.toString().let { it.startsWith("OverridenBToString(a1 = A@") && ", a2 = A@" in it }) { b.toString() } // not data class yet
 
     return "OK"
 }

core/descriptors/src/org/jetbrains/kotlin/resolve/inlineClassesUtils.kt

@@ -8,7 +8,10 @@ package org.jetbrains.kotlin.resolve
 import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.name.ClassId
 import org.jetbrains.kotlin.name.FqName
-import org.jetbrains.kotlin.types.*
+import org.jetbrains.kotlin.types.KotlinType
+import org.jetbrains.kotlin.types.TypeSubstitutor
+import org.jetbrains.kotlin.types.TypeUtils
+import org.jetbrains.kotlin.types.Variance
 import org.jetbrains.kotlin.utils.addToStdlib.safeAs
 
 val JVM_INLINE_ANNOTATION_FQ_NAME = FqName("kotlin.jvm.JvmInline")
@@ -16,7 +19,8 @@ val JVM_INLINE_ANNOTATION_CLASS_ID = ClassId.topLevel(JVM_INLINE_ANNOTATION_FQ_N
 
 // FIXME: DeserializedClassDescriptor in reflection do not have @JvmInline annotation, that we
 // FIXME: would like to check as well.
-fun DeclarationDescriptor.isInlineClass(): Boolean = this is ClassDescriptor && (isInline || isValue)
+fun DeclarationDescriptor.isInlineClass(): Boolean =
+    this is ClassDescriptor && (isInline || isValue) && unsubstitutedPrimaryConstructor?.valueParameters?.size == 1
 
 fun KotlinType.unsubstitutedUnderlyingType(): KotlinType? =
     constructor.declarationDescriptor.safeAs<ClassDescriptor>()?.inlineClassRepresentation?.underlyingType