data class MultipleFailuresResult(val failures: List<SingleFailureResult>) :
    FailingResult // TODO: should this exist at all?


sealed interface UnsupportedLanguageFeature {
    data object PackageHeader : UnsupportedLanguageFeature
    data object TypeDeclaration : UnsupportedLanguageFeature
    data object CollectionLiteral : UnsupportedLanguageFeature
    data object SupertypeUsage : UnsupportedLanguageFeature

            codeFailures = collectFailures(statements)
        )
    }

    private
    fun packageHeader(tree: CachingLightTree, node: LighterASTNode): List<FailingResult> =
        when {
            tree.children(node).isNotEmpty() -> listOf(tree.unsupportedNoOffset(node, node, UnsupportedLanguageFeature.PackageHeader))
            else -> listOf()
        }

    private

    @Test
    fun `rejects explicit package declaration`() {
        val code = "package com.example"
        val expected =
            """
            UnsupportedConstruct(
                languageFeature = PackageHeader,
                potentialElementSource = indexes: 0..19, line/column: 1/1..1/20, file: test,
                erroneousSource = indexes: 0..19, line/column: 1/1..1/20, file: test
            )
            """.trimIndent()