)


sealed interface ErrorReason {
    data class AmbiguousImport(val fqName: FqName) : ErrorReason
    data class UnresolvedReference(val reference: Expr) : ErrorReason
    data class NonReadableProperty(val property: DataProperty) : ErrorReason
    data class ReadOnlyPropertyAssignment(val property: DataProperty) : ErrorReason
    data class UnresolvedFunctionCallArguments(val functionCall: FunctionCall) : ErrorReason

            is ErrorReason.ValReassignment,
            is ErrorReason.AmbiguousFunctions,
            is ErrorReason.AmbiguousImport,
            ErrorReason.DanglingPureExpression,
            is ErrorReason.NonReadableProperty,
            ErrorReason.UnitAssignment, // TODO: should we still check for this?
            ErrorReason.AccessOnCurrentReceiverOnlyViolation -> error("not expected here")
        }
    }.distinct()

        assertTrue { result.errors.any { it.errorReason is ErrorReason.UnresolvedAssignmentRhs } }
        val nonReadablePropertyError = result.errors.mapNotNull { it.errorReason as? ErrorReason.NonReadableProperty }.single()
        assertEquals("z", nonReadablePropertyError.property.name)
    }

    @Test
    fun `if multiple property extractors have properties with the same name, first wins`() {

                    checkAccessOnCurrentReceiver(result)
                    if (result.property.isWriteOnly) {
                        errorCollector.collect(ResolutionError(result.originElement, ErrorReason.NonReadableProperty(result.property)))
                        return null
                    } else {
                        return result
                    }
                } else {
                    return result

        ErrorReason.AccessOnCurrentReceiverOnlyViolation -> "this member can only be accessed on a current receiver"
        is ErrorReason.NonReadableProperty -> "property cannot be used as a value: '${errorReason.property.name}'"
    }

    private
    fun describedUnassignedValueUsage(unassigned: AssignmentTraceElement.FailedToRecordAssignment): String {