FIR IDE: resolve by-name-parameter call

idea/idea-fir/tests/org/jetbrains/kotlin/idea/resolve/FirReferenceResolveTestGenerated.java

@@ -279,6 +279,11 @@ public class FirReferenceResolveTestGenerated extends AbstractFirReferenceResolv
         runTest("idea/testData/resolve/references/PackageReferenceInImport.kt");
     }
 
+    @TestMetadata("parameterByName.kt")
+    public void testParameterByName() throws Exception {
+        runTest("idea/testData/resolve/references/parameterByName.kt");
+    }
+
     @TestMetadata("PropertyPlaceInClassObjectInObject.kt")
     public void testPropertyPlaceInClassObjectInObject() throws Exception {
         runTest("idea/testData/resolve/references/PropertyPlaceInClassObjectInObject.kt");

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

@@ -24,6 +24,7 @@ import org.jetbrains.kotlin.fir.types.FirResolvedTypeRef
 import org.jetbrains.kotlin.fir.types.classId
 import org.jetbrains.kotlin.idea.fir.*
 import org.jetbrains.kotlin.idea.fir.low.level.api.api.getOrBuildFir
+import org.jetbrains.kotlin.idea.fir.low.level.api.api.getOrBuildFirSafe
 import org.jetbrains.kotlin.idea.frontend.api.fir.KtFirAnalysisSession
 import org.jetbrains.kotlin.idea.frontend.api.fir.KtSymbolByFirBuilder
 import org.jetbrains.kotlin.idea.frontend.api.fir.buildSymbol
@@ -35,6 +36,7 @@ import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi.psiUtil.collectDescendantsOfType
 import org.jetbrains.kotlin.psi.psiUtil.getNonStrictParentOfType
 import org.jetbrains.kotlin.psi.psiUtil.getQualifiedExpressionForSelector
+import org.jetbrains.kotlin.utils.addToStdlib.firstNotNullResult
 
 internal object FirReferenceResolveHelper {
     fun FirResolvedTypeRef.toTargetSymbol(session: FirSession, symbolBuilder: KtSymbolByFirBuilder): KtSymbol? {
@@ -155,10 +157,32 @@ internal object FirReferenceResolveHelper {
             is FirReturnExpression -> getSymbolsByReturnExpression(expression, fir, symbolBuilder)
             is FirErrorNamedReference -> getSymbolsByErrorNamedReference(fir, symbolBuilder)
             is FirResolvable -> getSymbolsByResolvable(fir, expression, session, symbolBuilder)
+            is FirNamedArgumentExpression -> getSymbolsByNameArgumentExpression(expression, analysisSession, symbolBuilder)
             else -> handleUnknownFirElement(expression, analysisSession, session, symbolBuilder)
         }
     }
 
+    private fun getSymbolsByNameArgumentExpression(
+        expression: KtSimpleNameExpression,
+        analysisSession: KtFirAnalysisSession,
+        symbolBuilder: KtSymbolByFirBuilder
+    ): Collection<KtSymbol> {
+        val ktValueArgumentName = expression.parent as? KtValueArgumentName ?: return emptyList()
+        val ktValueArgument = ktValueArgumentName.parent as? KtValueArgument ?: return emptyList()
+        val ktValueArgumentList = ktValueArgument.parent as? KtValueArgumentList ?: return emptyList()
+        val ktCallExpression = ktValueArgumentList.parent as? KtCallExpression ?: return emptyList()
+
+        val firCall = ktCallExpression.getOrBuildFirSafe<FirFunctionCall>(analysisSession.firResolveState) ?: return emptyList()
+        val parameter = firCall.findCorrespondingParameter(ktValueArgument) ?: return emptyList()
+        return listOfNotNull(parameter.buildSymbol(symbolBuilder))
+    }
+
+    private fun FirFunctionCall.findCorrespondingParameter(ktValueArgument: KtValueArgument): FirValueParameter? =
+        argumentMapping?.entries?.firstNotNullResult { (firArgument, firParameter) ->
+            if (firArgument.psi == ktValueArgument) firParameter
+            else null
+        }
+
     private fun handleUnknownFirElement(
         expression: KtSimpleNameExpression,
         analysisSession: KtFirAnalysisSession,

idea/testData/resolve/references/JavaParameter.kt

@@ -1,5 +1,3 @@
-// IGNORE_FIR
-
 lateinit var x: java.lang.Readable
 lateinit var y: java.nio.CharBuffer
 

idea/testData/resolve/references/parameterByName.kt

@@ -0,0 +1,7 @@
+fun sum(aa: Int, bb: Int) = a + b
+
+fun main() {
+    println(sum(b<caret>b = 1, aa = 2))
+}
+
+// REF: bb

idea/tests/org/jetbrains/kotlin/idea/resolve/ReferenceResolveTestGenerated.java

@@ -279,6 +279,11 @@ public class ReferenceResolveTestGenerated extends AbstractReferenceResolveTest
         runTest("idea/testData/resolve/references/PackageReferenceInImport.kt");
     }
 
+    @TestMetadata("parameterByName.kt")
+    public void testParameterByName() throws Exception {
+        runTest("idea/testData/resolve/references/parameterByName.kt");
+    }
+
     @TestMetadata("PropertyPlaceInClassObjectInObject.kt")
     public void testPropertyPlaceInClassObjectInObject() throws Exception {
         runTest("idea/testData/resolve/references/PropertyPlaceInClassObjectInObject.kt");