kotlin-fork/idea/testData/findUsages/stdlibUsages/LibraryMemberFunctionUsagesInStdlib.0.kt

// PSI_ELEMENT: org.jetbrains.kotlin.psi.KtNamedFunction
// OPTIONS: usages
// FIND_BY_REF
// WITH_FILE_NAME
// FIR_IGNORE

package usages

fun test() {
    val f = mapOf(Pair("1","2")).keys.<caret>single( { true } )
}