KT-28235: Make sure array access produces unique elements

This requires generating calls on-demand in
LValueWithGetterAndSetterCalls.

compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/AssignmentGenerator.kt

@@ -263,19 +263,20 @@ class AssignmentGenerator(statementGenerator: StatementGenerator) : StatementGen
         ktLeft: KtArrayAccessExpression,
         origin: IrStatementOrigin
     ): ArrayAccessAssignmentReceiver {
-        val irArray = ktLeft.arrayExpression!!.genExpr()
-        val irIndexExpressions = ktLeft.indexExpressions.map { it.genExpr() }
-
         val indexedGetResolvedCall = get(BindingContext.INDEXED_LVALUE_GET, ktLeft)
-        val indexedGetCall = indexedGetResolvedCall?.let { statementGenerator.pregenerateCallReceivers(it) }
-
         val indexedSetResolvedCall = get(BindingContext.INDEXED_LVALUE_SET, ktLeft)
-        val indexedSetCall = indexedSetResolvedCall?.let { statementGenerator.pregenerateCallReceivers(it) }
 
         return ArrayAccessAssignmentReceiver(
-            irArray, irIndexExpressions, indexedGetCall, indexedSetCall,
+            ktLeft.arrayExpression!!.genExpr(),
+            ktLeft.indexExpressions.map { it.genExpr() },
+            indexedGetResolvedCall,
+            indexedSetResolvedCall,
+            { indexedGetResolvedCall?.let { statementGenerator.pregenerateCallReceivers(it) } },
+            { indexedSetResolvedCall?.let { statementGenerator.pregenerateCallReceivers(it) } },
             CallGenerator(statementGenerator),
-            ktLeft.startOffsetSkippingComments, ktLeft.endOffset, origin
+            ktLeft.startOffsetSkippingComments,
+            ktLeft.endOffset,
+            origin
         )
     }
 

compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/intermediate/ArrayAccessAssignmentReceiver.kt

@@ -16,31 +16,40 @@
 
 package org.jetbrains.kotlin.psi2ir.intermediate
 
+import org.jetbrains.kotlin.descriptors.FunctionDescriptor
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrStatementOrigin
 import org.jetbrains.kotlin.ir.expressions.impl.IrBlockImpl
 import org.jetbrains.kotlin.ir.expressions.impl.inlineStatement
 import org.jetbrains.kotlin.ir.expressions.isAssignmentOperatorWithResult
 import org.jetbrains.kotlin.psi2ir.generators.CallGenerator
+import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall
 import org.jetbrains.kotlin.types.KotlinType
-import java.lang.AssertionError
 
 class ArrayAccessAssignmentReceiver(
     private val irArray: IrExpression,
     private val irIndices: List<IrExpression>,
-    private val indexedGetCall: CallBuilder?,
-    private val indexedSetCall: CallBuilder?,
+    private val indexedGetResolvedCall: ResolvedCall<FunctionDescriptor>?,
+    private val indexedSetResolvedCall: ResolvedCall<FunctionDescriptor>?,
+    private val indexedGetCall: () -> CallBuilder?,
+    private val indexedSetCall: () -> CallBuilder?,
     private val callGenerator: CallGenerator,
     private val startOffset: Int,
     private val endOffset: Int,
     private val origin: IrStatementOrigin
 ) : AssignmentReceiver {
 
-    private val kotlinType: KotlinType =
-        indexedGetCall?.run { descriptor.returnType!! } ?: indexedSetCall?.run { descriptor.valueParameters.last().type }
-        ?: throw AssertionError("Array access should have either indexed-get call or indexed-set call")
+    private val descriptor =
+        indexedGetResolvedCall?.resultingDescriptor
+            ?: indexedSetResolvedCall?.resultingDescriptor
+            ?: throw AssertionError("Array access should have either indexed-get call or indexed-set call")
 
     override fun assign(withLValue: (LValue) -> IrExpression): IrExpression {
+        val kotlinType: KotlinType =
+            indexedGetResolvedCall?.run { resultingDescriptor.returnType!! }
+                ?: indexedSetResolvedCall?.run { resultingDescriptor.valueParameters.last().type }
+                ?: throw AssertionError("Array access should have either indexed-get call or indexed-set call")
+
         val hasResult = origin.isAssignmentOperatorWithResult()
         val resultType = if (hasResult) kotlinType else callGenerator.context.builtIns.unitType
         val irResultType = callGenerator.translateType(resultType)
@@ -52,11 +61,11 @@ class ArrayAccessAssignmentReceiver(
             callGenerator.scope.createTemporaryVariableInBlock(callGenerator.context, irIndex, irBlock, "index$i")
         }
 
-        indexedGetCall?.fillArrayAndIndexArguments(irArrayValue, irIndexValues)
-        indexedSetCall?.fillArrayAndIndexArguments(irArrayValue, irIndexValues)
         val irLValue = LValueWithGetterAndSetterCalls(
             callGenerator,
-            indexedGetCall, indexedSetCall,
+            descriptor,
+            { indexedGetCall()?.fillArrayAndIndexArguments(irArrayValue, irIndexValues) },
+            { indexedSetCall()?.fillArrayAndIndexArguments(irArrayValue, irIndexValues) },
             callGenerator.translateType(kotlinType),
             startOffset, endOffset, origin
         )
@@ -66,16 +75,16 @@ class ArrayAccessAssignmentReceiver(
     }
 
     override fun assign(value: IrExpression): IrExpression {
-        if (indexedSetCall == null) throw AssertionError("Array access without indexed-get call")
-        indexedSetCall.setExplicitReceiverValue(OnceExpressionValue(irArray))
+        val call = indexedSetCall() ?: throw AssertionError("Array access without indexed-get call")
+        call.setExplicitReceiverValue(OnceExpressionValue(irArray))
         irIndices.forEachIndexed { i, irIndex ->
-            indexedSetCall.irValueArgumentsByIndex[i] = irIndex
+            call.irValueArgumentsByIndex[i] = irIndex
         }
-        indexedSetCall.lastArgument = value
-        return callGenerator.generateCall(startOffset, endOffset, indexedSetCall, IrStatementOrigin.EQ)
+        call.lastArgument = value
+        return callGenerator.generateCall(startOffset, endOffset, call, IrStatementOrigin.EQ)
     }
 
-    private fun CallBuilder.fillArrayAndIndexArguments(arrayValue: IntermediateValue, indexValues: List<IntermediateValue>) {
+    private fun CallBuilder.fillArrayAndIndexArguments(arrayValue: IntermediateValue, indexValues: List<IntermediateValue>) = apply {
         setExplicitReceiverValue(arrayValue)
         indexValues.forEachIndexed { i, irIndexValue ->
             irValueArgumentsByIndex[i] = irIndexValue.load()

compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/intermediate/LValueWithGetterAndSetterCalls.kt

@@ -21,31 +21,27 @@ import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrStatementOrigin
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.psi2ir.generators.CallGenerator
-import org.jetbrains.kotlin.types.KotlinType
 
 class LValueWithGetterAndSetterCalls(
     val callGenerator: CallGenerator,
-    val getterCall: CallBuilder?,
-    val setterCall: CallBuilder?,
+    val descriptor: CallableDescriptor,
+    val getterCall: () -> CallBuilder?,
+    val setterCall: () -> CallBuilder?,
     override val type: IrType,
     val startOffset: Int,
     val endOffset: Int,
     val origin: IrStatementOrigin? = null
 ) : LValue {
 
-    private val descriptor: CallableDescriptor =
-        getterCall?.descriptor ?: setterCall?.descriptor
-        ?: throw AssertionError("Call-based LValue should have either a getter or a setter call")
-
     override fun load(): IrExpression {
-        if (getterCall == null) throw AssertionError("No getter call for $descriptor")
-        return callGenerator.generateCall(startOffset, endOffset, getterCall, origin)
+        val call = getterCall() ?: throw AssertionError("No getter call for $descriptor")
+        return callGenerator.generateCall(startOffset, endOffset, call, origin)
     }
 
     override fun store(irExpression: IrExpression): IrExpression {
-        if (setterCall == null) throw AssertionError("No setter call for $descriptor")
-        setterCall.irValueArgumentsByIndex[setterCall.argumentsCount - 1] = irExpression
-        return callGenerator.generateCall(startOffset, endOffset, setterCall, origin)
+        val call = setterCall() ?: throw AssertionError("No setter call for $descriptor")
+        call.irValueArgumentsByIndex[call.argumentsCount - 1] = irExpression
+        return callGenerator.generateCall(startOffset, endOffset, call, origin)
     }
 
 }

compiler/tests-common/tests/org/jetbrains/kotlin/ir/AbstractIrTextTestCase.kt

@@ -136,8 +136,18 @@ abstract class AbstractIrTextTestCase : AbstractIrGeneratorTestCase() {
             }
         }
 
+        private val elementsAreUniqueChecker = object : IrElementVisitorVoid {
+            private val elements = HashSet<IrElement>()
+
+            override fun visitElement(element: IrElement) {
+                require(elements.add(element)) { "Non-unique element: ${element.render()}" }
+                element.acceptChildrenVoid(this)
+            }
+        }
+
         fun verifyWithAssert(irFile: IrFile) {
             irFile.acceptChildrenVoid(this)
+            irFile.acceptChildrenVoid(elementsAreUniqueChecker)
             TestCase.assertFalse(errorsAsMessage + "\n\n\n" + irFile.dump(), hasErrors)
         }