private static @Nullable Couple<String> getCallDescriptor(PsiExpression expression) {
    if (expression instanceof PsiMethodCallExpression) {
      PsiReferenceExpression methodExpression = ((PsiMethodCallExpression)expression).getMethodExpression();
      PsiExpression qualifierExpression = methodExpression.getQualifierExpression();
      String qualifiedName = qualifierExpression != null ? qualifierExpression.getText() : null;
      String methodName = methodExpression.getReferenceName();
      if (methodName == null) return null;
      
      PsiExpression[] expressions = ((PsiMethodCallExpression)expression).getArgumentList().getExpressions();
      if (expressions.length == 0) {
        return null;
      }
      if (!(expressions[0] instanceof PsiLiteralExpression)) {
        return null;
      }
      return Couple.of(qualifiedName, methodName);
    }
    return null;
  }
private static @Nullable Couple<String> getCallDescriptor(PsiExpression expression)