FIR IDE: introduce KtFirCollectionLiteralReference

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/fir/KtDeclarationAndFirDeclarationEqualityChecker.kt

@@ -16,6 +16,7 @@ import org.jetbrains.kotlin.fir.resolve.ScopeSession
 import org.jetbrains.kotlin.fir.scopes.FirScope
 import org.jetbrains.kotlin.fir.scopes.FirScopeProvider
 import org.jetbrains.kotlin.fir.scopes.FirTypeScope
+import org.jetbrains.kotlin.fir.symbols.StandardClassIds
 import org.jetbrains.kotlin.fir.types.*
 import org.jetbrains.kotlin.psi.KtFunction
 import org.jetbrains.kotlin.psi.KtTypeReference
@@ -89,12 +90,27 @@ object KtDeclarationAndFirDeclarationEqualityChecker {
             else -> error("Invalid type reference $this")
         }
         return if (isVararg) {
-            "kotlin.Array<out $rendered>"
+            rendered.asArrayType()
         } else {
             rendered
         }
     }
 
+    private fun String.asArrayType(): String {
+        classIdToName[this]?.let { return it }
+        return "kotlin.Array<out $this>"
+    }
+
+    @OptIn(ExperimentalStdlibApi::class)
+    private val classIdToName: Map<String, String> = buildList {
+        StandardClassIds.primitiveArrayTypeByElementType.mapTo(this) { (classId, arrayClassId) ->
+            classId.asString().replace('/', '.') to arrayClassId.asString().replace('/', '.')
+        }
+        StandardClassIds.unsignedArrayTypeByElementType.mapTo(this) { (classId, arrayClassId) ->
+            classId.asString().replace('/', '.') to arrayClassId.asString().replace('/', '.')
+        }
+    }.toMap()
+
     private fun FirTypeProjection.renderTypeAsKotlinType() = when (this) {
         is FirStarProjection -> "*"
         is FirTypeProjectionWithVariance -> buildString {

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/references/KotlinFirReferenceContributor.kt

@@ -15,6 +15,7 @@ class KotlinFirReferenceContributor : KotlinReferenceProviderContributor {
             registerProvider(factory = ::KtFirDestructuringDeclarationReference)
             registerProvider(factory = ::KtFirArrayAccessReference)
             registerProvider(factory = ::KtFirConstructorDelegationReference)
+            registerProvider(factory = ::KtFirCollectionLiteralReference)
         }
     }
 }

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/references/KtFirCollectionLiteralReference.kt

@@ -0,0 +1,59 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.idea.references
+
+import org.jetbrains.kotlin.fir.declarations.FirFunction
+import org.jetbrains.kotlin.fir.declarations.FirSimpleFunction
+import org.jetbrains.kotlin.fir.expressions.FirArrayOfCall
+import org.jetbrains.kotlin.fir.resolve.firSymbolProvider
+import org.jetbrains.kotlin.fir.symbols.CallableId
+import org.jetbrains.kotlin.fir.symbols.StandardClassIds
+import org.jetbrains.kotlin.fir.symbols.impl.FirFunctionSymbol
+import org.jetbrains.kotlin.fir.types.ConeClassLikeType
+import org.jetbrains.kotlin.fir.types.coneType
+import org.jetbrains.kotlin.fir.types.coneTypeSafe
+import org.jetbrains.kotlin.idea.fir.low.level.api.api.getOrBuildFirSafe
+import org.jetbrains.kotlin.idea.frontend.api.KtAnalysisSession
+import org.jetbrains.kotlin.idea.frontend.api.fir.KtFirAnalysisSession
+import org.jetbrains.kotlin.idea.frontend.api.symbols.KtSymbol
+import org.jetbrains.kotlin.name.ClassId
+import org.jetbrains.kotlin.name.FqName
+import org.jetbrains.kotlin.name.Name
+import org.jetbrains.kotlin.psi.KtCollectionLiteralExpression
+
+class KtFirCollectionLiteralReference(
+    expression: KtCollectionLiteralExpression
+) : KtCollectionLiteralReference(expression), KtFirReference {
+    override fun KtAnalysisSession.resolveToSymbols(): Collection<KtSymbol> {
+        check(this is KtFirAnalysisSession)
+        val fir = element.getOrBuildFirSafe<FirArrayOfCall>(firResolveState) ?: return emptyList()
+        val type = fir.typeRef.coneTypeSafe<ConeClassLikeType>() ?: return listOfNotNull(arrayOfSymbol(arrayOf))
+        val call = arrayTypeToArrayOfCall[type.lookupTag.classId] ?: arrayOf
+        return listOfNotNull(arrayOfSymbol(call))
+    }
+
+    private fun KtFirAnalysisSession.arrayOfSymbol(identifier: Name): KtSymbol? {
+        val fir = firResolveState.rootModuleSession.firSymbolProvider.getTopLevelCallableSymbols(kotlinPackage, identifier).firstOrNull {
+            /* choose (for byte array)
+             * public fun byteArrayOf(vararg elements: kotlin.Byte): kotlin.ByteArray
+             */
+            (it as? FirFunctionSymbol<*>)?.fir?.valueParameters?.singleOrNull()?.isVararg == true
+        }?.fir as? FirSimpleFunction ?: return null
+        return firSymbolBuilder.buildFunctionSymbol(fir)
+    }
+
+    companion object {
+        private val kotlinPackage = FqName("kotlin")
+        private val arrayOf = Name.identifier("arrayOf")
+        private val arrayTypeToArrayOfCall = run {
+            StandardClassIds.primitiveArrayTypeByElementType.values + StandardClassIds.unsignedArrayTypeByElementType.values
+        }.associateWith { it.correspondingArrayOfCallFqName() }
+
+        private fun ClassId.correspondingArrayOfCallFqName(): Name =
+            Name.identifier("${shortClassName.identifier.decapitalize()}Of")
+
+    }
+}

idea/testData/resolve/references/CollectionLiteralLeft.kt

@@ -1,5 +1,3 @@
-// IGNORE_FIR
-
 val abc = <caret>[1, 2, 3]
 
 // REF: (kotlin).arrayOf(vararg T)

idea/testData/resolve/references/CollectionLiteralRight.kt

@@ -1,5 +1,3 @@
-// IGNORE_FIR
-
 val abc: IntArray = [1, 2, 3<caret>]
 
 // REF: (kotlin).intArrayOf(vararg kotlin.Int)