Kotlin: Fix array set operator extraction

Author: tamasvajk

java/kotlin-extractor/src/main/kotlin/KotlinFileExtractor.kt

@@ -2208,7 +2208,7 @@ open class KotlinFileExtractor(
                     tw.writeExprsKotlinType(id, type.kotlinResult.id)
                     binopDisp(id)
                 }
-                isFunction(target, "kotlin", "(some array type)", { isArrayType(it) }, "set") && c.origin == IrStatementOrigin.EQ -> {
+                isFunction(target, "kotlin", "(some array type)", { isArrayType(it) }, "set") && c.origin == IrStatementOrigin.EQ && c.dispatchReceiver != null -> {
                     val array = c.dispatchReceiver
                     val arrayIdx = c.getValueArgument(0)
                     val assignedValue = c.getValueArgument(1)

java/ql/test/kotlin/library-tests/operator-overloads/PrintAst.expected

@@ -33,9 +33,21 @@ test.kt:
 #    6|         3: [ExprStmt] <Expr>;
 #    6|           0: [ImplicitCoercionToUnitExpr] <implicit coercion to unit>
 #    6|             0: [TypeAccess] Unit
+#    6|             1: [MethodAccess] set(...)
+#    6|               -1: [TypeAccess] TestKt
+#    6|               0: [VarAccess] arr
+#    6|               1: [IntegerLiteral] 1
+#    6|               2: [IntegerLiteral] 2
+#    6|               3: [IntegerLiteral] 3
 #    7|         4: [ExprStmt] <Expr>;
 #    7|           0: [ImplicitCoercionToUnitExpr] <implicit coercion to unit>
 #    7|             0: [TypeAccess] Unit
+#    7|             1: [MethodAccess] set(...)
+#    7|               -1: [TypeAccess] TestKt
+#    7|               0: [VarAccess] arr
+#    7|               1: [IntegerLiteral] 1
+#    7|               2: [ClassInstanceExpr] new C(...)
+#    7|                 -3: [TypeAccess] C
 #   10|     2: [ExtensionMethod] get
 #   10|       3: [TypeAccess] String
 #-----|       4: (Parameters)

java/ql/test/kotlin/library-tests/operator-overloads/test.expected

@@ -1,2 +0,0 @@
-| test.kt:6:5:6:13 | Unexpected Array.set function signature |
-| test.kt:7:5:7:10 | Unexpected Array.set function signature |