@Nullable
 private static PsiType guessElementTypeFromReference(
     MethodPatternMap methodPatternMap, PsiElement ref, TextRange rangeToIgnore) {
   PsiElement refParent = ref.getParent();
   if (refParent instanceof PsiReferenceExpression) {
     PsiReferenceExpression parentExpr = (PsiReferenceExpression) refParent;
     if (ref.equals(parentExpr.getQualifierExpression())
         && parentExpr.getParent() instanceof PsiMethodCallExpression) {
       String methodName = parentExpr.getReferenceName();
       PsiMethodCallExpression methodCall = (PsiMethodCallExpression) parentExpr.getParent();
       PsiExpression[] args = methodCall.getArgumentList().getExpressions();
       MethodPattern pattern = methodPatternMap.findPattern(methodName, args.length);
       if (pattern != null) {
         if (pattern.parameterIndex < 0) { // return value
           if (methodCall.getParent() instanceof PsiTypeCastExpression
               && (rangeToIgnore == null || !rangeToIgnore.contains(methodCall.getTextRange()))) {
             return ((PsiTypeCastExpression) methodCall.getParent()).getType();
           }
         } else {
           return args[pattern.parameterIndex].getType();
         }
       }
     }
   }
   return null;
 }