bchavez/Bogus · error · ArgumentException

There are no values after exclusion to choose from.

Error message

There are no values after exclusion to choose from.

What it means

Thrown by Randomizer.Enum<T> when, after applying the exclude list, no enum names remain in the selection. The method computes selection = Enum.GetNames(T).Except(exclude) and rejects an empty result because there is nothing to pick.

Source

Thrown at Source/Bogus/Randomizer.cs:671

   /// <typeparam name="T">Must be an Enum</typeparam>
   /// <param name="exclude">Exclude enum values from being returned</param>
   public T Enum<T>(params T[] exclude) where T : struct, Enum
   {
      var e = typeof(T);
      if( !e.IsEnum() )
         throw new ArgumentException("When calling Enum<T>() with no parameters T must be an enum.");

      var selection = System.Enum.GetNames(e);

      if( exclude.Any() )
      {
         var excluded = exclude.Select(ex => System.Enum.GetName(e, ex));
         selection = selection.Except(excluded).ToArray();
      }

      if( !selection.Any() )
      {
         throw new ArgumentException("There are no values after exclusion to choose from.");
      }

      var val = this.ArrayElement(selection);

      System.Enum.TryParse(val, out T picked);
      return picked;
   }

   /// <summary>
   /// Picks a random subset of enum values in T:Enum.
   /// </summary>
   /// <typeparam name="T">The enum.</typeparam>
   /// <param name="count">The number of enums to pick.</param>
   /// <param name="exclude">Any enums that should be excluded before picking.</param>
   public T[] EnumValues<T>(int? count = null, params T[] exclude) where T : Enum
   {
      T[] enums;
      if( exclude.Length > 0)

View on GitHub (pinned to 6ece18c5c2)

Solutions

1. Ensure at least one enum member is not in the exclude list.
2. Validate before calling: var remaining = Enum.GetValues<T>().Except(exclude); require remaining.Any().
3. Reconsider the exclude set if it matches all members.

Example fix

// before
var v = f.Random.Enum(Enum.GetValues<MyEnum>().ToArray());
// after
var pool = Enum.GetValues<MyEnum>().Except(new[]{MyEnum.None}).ToArray();
var v = pool.Length > 0 ? f.Random.Enum(pool) : MyEnum.None;

static T SafeEnum<T>(Bogus.Randomizer r, params T[] exclude) where T : struct, Enum {
    var remaining = System.Enum.GetValues<T>().Except(exclude).ToArray();
    if (remaining.Length == 0) throw new InvalidOperationException("all enum values excluded");
    return r.Enum(exclude);
}

bool HasRemaining<T>(params T[] exclude) where T : struct, Enum => System.Enum.GetValues<T>().Except(exclude).Any();

try { return r.Enum(exclude); }
catch (ArgumentException ex) when (ex.Message.Contains("no values after exclusion")) {
    return System.Enum.GetValues<T>()[0]; // default first member
}

When it happens

Trigger: Calling f.Random.Enum(exclude: everyValue) i.e. excluding all members of the enum, or excluding the sole member of a single-value enum.

Common situations: Building exclude lists dynamically and accidentally covering the whole enum; enums with one value where the caller excludes it.

Related errors

• When calling Enum<T>() with no parameters T must be an enum.
• max digit can't be lager than 9 or smaller than 0
• The min/max range is invalid. The minimum value '{min}' is g
• The specified range does not contain any even numbers.
• The specified range does not contain any odd numbers.

AI-assisted analysis of bchavez/Bogus@6ece18c5c2 (2026-08-13). Data as JSON: /api/errors/5adcaced7916730b. Report an issue: GitHub.