diff --git a/compiler/frontend/src/org/jetbrains/kotlin/psi/KtOperationReferenceExpression.kt b/compiler/frontend/src/org/jetbrains/kotlin/psi/KtOperationReferenceExpression.kt
index 861418b0e54..f5580b8161d 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/psi/KtOperationReferenceExpression.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/psi/KtOperationReferenceExpression.kt
@@ -20,10 +20,7 @@ import com.intellij.lang.ASTNode
 import com.intellij.psi.PsiElement
 import com.intellij.psi.impl.source.tree.TreeElement
 import org.jetbrains.kotlin.lexer.KtSingleValueToken
-import org.jetbrains.kotlin.lexer.KtToken
-import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.parsing.KotlinExpressionParsing
-import org.jetbrains.kotlin.resolve.constants.evaluate.binaryOperations
 import org.jetbrains.kotlin.types.expressions.OperatorConventions
 
 class KtOperationReferenceExpression(node: ASTNode) : KtSimpleNameExpressionImpl(node) {
@@ -31,4 +28,9 @@ class KtOperationReferenceExpression(node: ASTNode) : KtSimpleNameExpressionImpl
 
     val operationSignTokenType: KtSingleValueToken?
         get() = (firstChild as? TreeElement)?.elementType as? KtSingleValueToken
+
+    fun isConventionOperator(): Boolean {
+        val tokenType = operationSignTokenType ?: return false
+        return OperatorConventions.getNameForOperationSymbol(tokenType) != null
+    }
 }
diff --git a/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/CallResolverUtil.kt b/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/CallResolverUtil.kt
index 1bc8b1c6c24..d165f0ebdb9 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/CallResolverUtil.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/CallResolverUtil.kt
@@ -131,7 +131,7 @@ fun isConventionCall(call: Call): Boolean {
     val callElement = call.callElement
     if (callElement is KtArrayAccessExpression || callElement is KtDestructuringDeclarationEntry) return true
     val calleeExpression = call.calleeExpression as? KtOperationReferenceExpression ?: return false
-    return calleeExpression.operationSignTokenType != null
+    return calleeExpression.isConventionOperator()
 }
 
 fun isInfixCall(call: Call): Boolean {
diff --git a/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/checkers/OperatorCallChecker.kt b/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/checkers/OperatorCallChecker.kt
index 3a032690b5b..4fb68b77f58 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/checkers/OperatorCallChecker.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/checkers/OperatorCallChecker.kt
@@ -57,7 +57,7 @@ class OperatorCallChecker : CallChecker {
             return
         }
 
-        val isConventionOperator = element is KtOperationReferenceExpression && element.operationSignTokenType != null
+        val isConventionOperator = element is KtOperationReferenceExpression && element.isConventionOperator()
         if (isConventionOperator || element is KtArrayAccessExpression) {
             if (!functionDescriptor.isOperator) {
                 report(reportOn, functionDescriptor, context.trace)
diff --git a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/references/KtSimpleNameReference.kt b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/references/KtSimpleNameReference.kt
index 633e5b3a1e0..62d83187d45 100644
--- a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/references/KtSimpleNameReference.kt
+++ b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/references/KtSimpleNameReference.kt
@@ -213,16 +213,15 @@ class KtSimpleNameReference(expression: KtSimpleNameExpression) : KtSimpleRefere
                 val tokenType = element.operationSignTokenType
                 if (tokenType != null) {
                     val name = OperatorConventions.getNameForOperationSymbol(
-                            tokenType, element.parent is KtUnaryExpression, element.parent is KtBinaryExpression)
-                    if (name != null) { // can it be null ever?
-                        val counterpart = OperatorConventions.ASSIGNMENT_OPERATION_COUNTERPARTS[tokenType]
-                        if (counterpart != null) {
-                            val counterpartName = OperatorConventions.getNameForOperationSymbol(counterpart, false, true)!!
-                            return listOf(name, counterpartName)
-                        }
-                        else {
-                            return listOf(name)
-                        }
+                            tokenType, element.parent is KtUnaryExpression, element.parent is KtBinaryExpression
+                    ) ?: return emptyList()
+                    val counterpart = OperatorConventions.ASSIGNMENT_OPERATION_COUNTERPARTS[tokenType]
+                    if (counterpart != null) {
+                        val counterpartName = OperatorConventions.getNameForOperationSymbol(counterpart, false, true)!!
+                        return listOf(name, counterpartName)
+                    }
+                    else {
+                        return listOf(name)
                     }
                 }
             }