Generate parameter name in assertion for lateinit properties

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/LateinitLowering.kt

@@ -18,22 +18,26 @@ package org.jetbrains.kotlin.backend.common.lower
 
 import org.jetbrains.kotlin.backend.common.CommonBackendContext
 import org.jetbrains.kotlin.backend.common.FileLoweringPass
-import org.jetbrains.kotlin.descriptors.CallableMemberDescriptor
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.ir.IrStatement
+import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.builders.*
 import org.jetbrains.kotlin.ir.declarations.IrFile
 import org.jetbrains.kotlin.ir.declarations.IrFunction
 import org.jetbrains.kotlin.ir.declarations.IrProperty
 import org.jetbrains.kotlin.ir.expressions.IrBlock
 import org.jetbrains.kotlin.ir.expressions.impl.IrBlockImpl
+import org.jetbrains.kotlin.ir.expressions.impl.IrConstImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrExpressionBodyImpl
 import org.jetbrains.kotlin.ir.symbols.IrFieldSymbol
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
 import org.jetbrains.kotlin.types.KotlinType
 
-class LateinitLowering(val context: CommonBackendContext): FileLoweringPass {
+class LateinitLowering(
+    val context: CommonBackendContext,
+    private val generateParameterNameInAssertion: Boolean = false
+) : FileLoweringPass {
     override fun lower(irFile: IrFile) {
         irFile.transformChildrenVoid(object : IrElementTransformerVoid() {
             override fun visitProperty(declaration: IrProperty): IrStatement {
@@ -54,10 +58,12 @@ class LateinitLowering(val context: CommonBackendContext): FileLoweringPass {
                         irGetField(getter.dispatchReceiverParameter?.let { irGet(it.symbol) }, backingFieldSymbol)
                     )
                     block.statements.add(resultVar)
-                    val throwIfNull = irIfThenElse(context.builtIns.nothingType,
+                    val throwIfNull = irIfThenElse(
+                        context.builtIns.nothingType,
                         irNotEquals(irGet(resultVar.symbol), irNull()),
                         irReturn(irGet(resultVar.symbol)),
-                            irCall(throwErrorFunction))
+                        throwUninitializedPropertyAccessException(backingFieldSymbol)
+                    )
                     block.statements.add(throwIfNull)
                     getter.body = IrExpressionBodyImpl(startOffset, endOffset, block)
                 }
@@ -65,9 +71,23 @@ class LateinitLowering(val context: CommonBackendContext): FileLoweringPass {
         })
     }
 
+    private fun IrBuilderWithScope.throwUninitializedPropertyAccessException(backingFieldSymbol: IrFieldSymbol) =
+        irCall(throwErrorFunction).apply {
+            if (generateParameterNameInAssertion) {
+                putValueArgument(
+                    0,
+                    IrConstImpl.string(
+                        UNDEFINED_OFFSET,
+                        UNDEFINED_OFFSET,
+                        context.builtIns.stringType,
+                        backingFieldSymbol.descriptor.name.asString()
+                    )
+                )
+            }
+        }
+
     private val throwErrorFunction = context.ir.symbols.ThrowUninitializedPropertyAccessException
 
-    private fun IrBuilderWithScope.irBlock(type: KotlinType): IrBlock
+    private fun IrBuilderWithScope.irBlock(type: KotlinType): IrBlock = IrBlockImpl(startOffset, endOffset, type)
-            = IrBlockImpl(startOffset, endOffset, type)
 
 }

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmLower.kt

@@ -28,7 +28,9 @@ class JvmLower(val context: JvmBackendContext) {
         // TODO run lowering passes as callbacks in bottom-up visitor
         FileClassLowering(context).lower(irFile)
         KCallableNamePropertyLowering(context).lower(irFile)
-        LateinitLowering(context).lower(irFile)
+
+        LateinitLowering(context, true).lower(irFile)
+
         ConstAndJvmFieldPropertiesLowering().lower(irFile)
         PropertiesLowering().lower(irFile)