override fun doTestByMainFile(mainFile: KtFile, mainModule: KtTestModule, testServices: TestServices) {
        val actual = buildString {
            mainFile.accept(object : KtTreeVisitor<Int>() {
                override fun visitDeclaration(declaration: KtDeclaration, indent: Int): Void? {
                    if (declaration is KtTypeParameter) return null
                    append(" ".repeat(indent))