Fix swapped parameters in ArgumentException, ArgumentNullException cstrs (#1139)

* Fix swapped parameters in ArgumentException and ArgumentNullException cstrs

The constructors of ArgumentException and ArgumentNullException are inconsistent with each other, which results in their parameters being swapped here and there.

* Use named parameters for ArgumentException constructors

Cleans up some of the methods of EmbedBuilder to use simpler syntax as well

src/Discord.Net.Core/Entities/Emotes/Emote.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Globalization;
 
 namespace Discord
@@ -58,7 +58,7 @@ namespace Discord
         {
             if (TryParse(text, out Emote result))
                 return result;
-            throw new ArgumentException("Invalid emote format", nameof(text));
+            throw new ArgumentException(message: "Invalid emote format", paramName: nameof(text));
         }
 
         public static bool TryParse(string text, out Emote result)

src/Discord.Net.Core/Entities/Messages/EmbedBuilder.cs

@@ -29,7 +29,7 @@ namespace Discord
             get => _title;
             set
             {
-                if (value?.Length > MaxTitleLength) throw new ArgumentException($"Title length must be less than or equal to {MaxTitleLength}.", nameof(Title));
+                if (value?.Length > MaxTitleLength) throw new ArgumentException(message: $"Title length must be less than or equal to {MaxTitleLength}.", paramName: nameof(Title));
                 _title = value;
             }
         }
@@ -38,7 +38,7 @@ namespace Discord
             get => _description;
             set
             {
-                if (value?.Length > MaxDescriptionLength) throw new ArgumentException($"Description length must be less than or equal to {MaxDescriptionLength}.", nameof(Description));
+                if (value?.Length > MaxDescriptionLength) throw new ArgumentException(message: $"Description length must be less than or equal to {MaxDescriptionLength}.", paramName: nameof(Description));
                 _description = value;
             }
         }
@@ -48,7 +48,7 @@ namespace Discord
             get => _url;
             set
             {
-                if (!value.IsNullOrUri()) throw new ArgumentException("Url must be a well-formed URI", nameof(Url));
+                if (!value.IsNullOrUri()) throw new ArgumentException(message: "Url must be a well-formed URI", paramName: nameof(Url));
                 _url = value;
             }
         }
@@ -57,7 +57,7 @@ namespace Discord
             get => _thumbnail?.Url;
             set
             {
-                if (!value.IsNullOrUri()) throw new ArgumentException("Url must be a well-formed URI", nameof(ThumbnailUrl));
+                if (!value.IsNullOrUri()) throw new ArgumentException(message: "Url must be a well-formed URI", paramName: nameof(ThumbnailUrl));
                 _thumbnail = new EmbedThumbnail(value, null, null, null);
             }
         }
@@ -66,7 +66,7 @@ namespace Discord
             get => _image?.Url;
             set
             {
-                if (!value.IsNullOrUri()) throw new ArgumentException("Url must be a well-formed URI", nameof(ImageUrl));
+                if (!value.IsNullOrUri()) throw new ArgumentException(message: "Url must be a well-formed URI", paramName: nameof(ImageUrl));
                 _image = new EmbedImage(value, null, null, null);
             }
         }
@@ -75,8 +75,8 @@ namespace Discord
             get => _fields;
             set
             {
-                if (value == null) throw new ArgumentNullException("Cannot set an embed builder's fields collection to null", nameof(Fields));
-                if (value.Count > MaxFieldCount) throw new ArgumentException($"Field count must be less than or equal to {MaxFieldCount}.", nameof(Fields));
+                if (value == null) throw new ArgumentNullException(paramName: nameof(Fields), message: "Cannot set an embed builder's fields collection to null");
+                if (value.Count > MaxFieldCount) throw new ArgumentException(message: $"Field count must be less than or equal to {MaxFieldCount}.", paramName: nameof(Fields));
                 _fields = value;
             }
         }
@@ -200,7 +200,7 @@ namespace Discord
         {
             if (Fields.Count >= MaxFieldCount)
             {
-                throw new ArgumentException($"Field count must be less than or equal to {MaxFieldCount}.", nameof(field));
+                throw new ArgumentException(message: $"Field count must be less than or equal to {MaxFieldCount}.", paramName: nameof(field));
             }
 
             Fields.Add(field);
@@ -239,8 +239,8 @@ namespace Discord
             get => _name;
             set
             {
-                if (string.IsNullOrWhiteSpace(value)) throw new ArgumentException("Field name must not be null, empty or entirely whitespace.", nameof(Name));
-                if (value.Length > MaxFieldNameLength) throw new ArgumentException($"Field name length must be less than or equal to {MaxFieldNameLength}.", nameof(Name));
+                if (string.IsNullOrWhiteSpace(value)) throw new ArgumentException(message: "Field name must not be null, empty or entirely whitespace.", paramName: nameof(Name));
+                if (value.Length > MaxFieldNameLength) throw new ArgumentException(message: $"Field name length must be less than or equal to {MaxFieldNameLength}.", paramName: nameof(Name));
                 _name = value;
             }
         }
@@ -251,8 +251,8 @@ namespace Discord
             set
             {
                 var stringValue = value?.ToString();
-                if (string.IsNullOrEmpty(stringValue)) throw new ArgumentException("Field value must not be null or empty.", nameof(Value));
-                if (stringValue.Length > MaxFieldValueLength) throw new ArgumentException($"Field value length must be less than or equal to {MaxFieldValueLength}.", nameof(Value));
+                if (string.IsNullOrEmpty(stringValue)) throw new ArgumentException(message: "Field value must not be null or empty.", paramName: nameof(Value));
+                if (stringValue.Length > MaxFieldValueLength) throw new ArgumentException(message: $"Field value length must be less than or equal to {MaxFieldValueLength}.", paramName: nameof(Value));
                 _value = stringValue;
             }
         }
@@ -290,7 +290,7 @@ namespace Discord
             get => _name;
             set
             {
-                if (value?.Length > MaxAuthorNameLength) throw new ArgumentException($"Author name length must be less than or equal to {MaxAuthorNameLength}.", nameof(Name));
+                if (value?.Length > MaxAuthorNameLength) throw new ArgumentException(message: $"Author name length must be less than or equal to {MaxAuthorNameLength}.", paramName: nameof(Name));
                 _name = value;
             }
         }
@@ -299,7 +299,7 @@ namespace Discord
             get => _url;
             set
             {
-                if (!value.IsNullOrUri()) throw new ArgumentException("Url must be a well-formed URI", nameof(Url));
+                if (!value.IsNullOrUri()) throw new ArgumentException(message: "Url must be a well-formed URI", paramName: nameof(Url));
                 _url = value;
             }
         }
@@ -308,7 +308,7 @@ namespace Discord
             get => _iconUrl;
             set
             {
-                if (!value.IsNullOrUri()) throw new ArgumentException("Url must be a well-formed URI", nameof(IconUrl));
+                if (!value.IsNullOrUri()) throw new ArgumentException(message: "Url must be a well-formed URI", paramName: nameof(IconUrl));
                 _iconUrl = value;
             }
         }
@@ -345,7 +345,7 @@ namespace Discord
             get => _text;
             set
             {
-                if (value?.Length > MaxFooterTextLength) throw new ArgumentException($"Footer text length must be less than or equal to {MaxFooterTextLength}.", nameof(Text));
+                if (value?.Length > MaxFooterTextLength) throw new ArgumentException(message: $"Footer text length must be less than or equal to {MaxFooterTextLength}.", paramName: nameof(Text));
                 _text = value;
             }
         }
@@ -354,7 +354,7 @@ namespace Discord
             get => _iconUrl;
             set
             {
-                if (!value.IsNullOrUri()) throw new ArgumentException("Url must be a well-formed URI", nameof(IconUrl));
+                if (!value.IsNullOrUri()) throw new ArgumentException(message: "Url must be a well-formed URI", paramName: nameof(IconUrl));
                 _iconUrl = value;
             }
         }

src/Discord.Net.Core/Entities/Permissions/ChannelPermissions.cs

@@ -29,7 +29,7 @@ namespace Discord
                 case ICategoryChannel _: return Category;
                 case IDMChannel _: return DM;
                 case IGroupChannel _: return Group;
-                default: throw new ArgumentException("Unknown channel type", nameof(channel));
+                default: throw new ArgumentException(message: "Unknown channel type", paramName: nameof(channel));
             }
         }
 

src/Discord.Net.Core/Utils/ConcurrentHashSet.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
@@ -160,23 +160,23 @@ namespace Discord
         public ConcurrentHashSet(IEnumerable<T> collection, IEqualityComparer<T> comparer) 
             : this(comparer)
         {
-            if (collection == null) throw new ArgumentNullException(nameof(collection));
+            if (collection == null) throw new ArgumentNullException(paramName: nameof(collection));
             InitializeFromCollection(collection);
         }
         public ConcurrentHashSet(int concurrencyLevel, IEnumerable<T> collection, IEqualityComparer<T> comparer)
             : this(concurrencyLevel, DefaultCapacity, false, comparer)
         {
-            if (collection == null) throw new ArgumentNullException(nameof(collection));
-            if (comparer == null) throw new ArgumentNullException(nameof(comparer));
+            if (collection == null) throw new ArgumentNullException(paramName: nameof(collection));
+            if (comparer == null) throw new ArgumentNullException(paramName: nameof(comparer));
             InitializeFromCollection(collection);
         }        
         public ConcurrentHashSet(int concurrencyLevel, int capacity, IEqualityComparer<T> comparer)
             : this(concurrencyLevel, capacity, false, comparer) { }
         internal ConcurrentHashSet(int concurrencyLevel, int capacity, bool growLockArray, IEqualityComparer<T> comparer)
         {
-            if (concurrencyLevel < 1) throw new ArgumentOutOfRangeException(nameof(concurrencyLevel));
-            if (capacity < 0) throw new ArgumentOutOfRangeException(nameof(capacity));
-            if (comparer == null) throw new ArgumentNullException(nameof(comparer));
+            if (concurrencyLevel < 1) throw new ArgumentOutOfRangeException(paramName: nameof(concurrencyLevel));
+            if (capacity < 0) throw new ArgumentOutOfRangeException(paramName: nameof(capacity));
+            if (comparer == null) throw new ArgumentNullException(paramName: nameof(comparer));
                         
             if (capacity < concurrencyLevel)
                 capacity = concurrencyLevel;
@@ -197,7 +197,7 @@ namespace Discord
         {
             foreach (var value in collection)
             {
-                if (value == null) throw new ArgumentNullException("key");
+                if (value == null) throw new ArgumentNullException(paramName: "key");
 
                 if (!TryAddInternal(value, _comparer.GetHashCode(value), false))
                     throw new ArgumentException();
@@ -209,7 +209,7 @@ namespace Discord
         
         public bool ContainsKey(T value)
         {
-            if (value == null) throw new ArgumentNullException("key");
+            if (value == null) throw new ArgumentNullException(paramName: "key");
             return ContainsKeyInternal(value, _comparer.GetHashCode(value));
         }
         private bool ContainsKeyInternal(T value, int hashcode)
@@ -232,7 +232,7 @@ namespace Discord
 
         public bool TryAdd(T value)
         {
-            if (value == null)  throw new ArgumentNullException("key");
+            if (value == null) throw new ArgumentNullException(paramName: "key");
             return TryAddInternal(value, _comparer.GetHashCode(value), true);
         }
         private bool TryAddInternal(T value, int hashcode, bool acquireLock)
@@ -281,7 +281,7 @@ namespace Discord
 
         public bool TryRemove(T value)
         {
-            if (value == null) throw new ArgumentNullException("key");
+            if (value == null) throw new ArgumentNullException(paramName: "key");
             return TryRemoveInternal(value);
         }        
         private bool TryRemoveInternal(T value)
@@ -467,4 +467,4 @@ namespace Discord
                 Monitor.Exit(_tables._locks[i]);
         }                
     }
-}
+}

src/Discord.Net.Core/Utils/MentionUtils.cs

@@ -21,7 +21,7 @@ namespace Discord
         {
             if (TryParseUser(text, out ulong id))
                 return id;
-            throw new ArgumentException("Invalid mention format", nameof(text));
+            throw new ArgumentException(message: "Invalid mention format", paramName: nameof(text));
         }
         /// <summary> Tries to parse a provided user mention string. </summary>
         public static bool TryParseUser(string text, out ulong userId)
@@ -45,7 +45,7 @@ namespace Discord
         {
             if (TryParseChannel(text, out ulong id))
                 return id;
-            throw new ArgumentException("Invalid mention format", nameof(text));
+            throw new ArgumentException(message: "Invalid mention format", paramName: nameof(text));
         }
         /// <summary>Tries to parse a provided channel mention string. </summary>
         public static bool TryParseChannel(string text, out ulong channelId)
@@ -66,7 +66,7 @@ namespace Discord
         {
             if (TryParseRole(text, out ulong id))
                 return id;
-            throw new ArgumentException("Invalid mention format", nameof(text));
+            throw new ArgumentException(message: "Invalid mention format", paramName: nameof(text));
         }
         /// <summary>Tries to parse a provided role mention string. </summary>
         public static bool TryParseRole(string text, out ulong roleId)

src/Discord.Net.Core/Utils/Preconditions.cs

@@ -10,8 +10,8 @@ namespace Discord
 
         private static ArgumentNullException CreateNotNullException(string name, string msg)
         {
-            if (msg == null) return new ArgumentNullException(name);
-            else return new ArgumentNullException(name, msg);
+            if (msg == null) return new ArgumentNullException(paramName: name);
+            else return new ArgumentNullException(paramName: name, message: msg);
         }
 
         //Strings
@@ -45,10 +45,7 @@ namespace Discord
         }        
 
         private static ArgumentException CreateNotEmptyException(string name, string msg)
-        {
-            if (msg == null) return new ArgumentException("Argument cannot be blank", name);
-            else return new ArgumentException(name, msg);
-        }
+            => new ArgumentException(message: msg ?? "Argument cannot be blank.", paramName: name);
 
         //Numerics
         public static void NotEqual(sbyte obj, sbyte value, string name, string msg = null) { if (obj == value) throw CreateNotEqualException(name, msg, value); }
@@ -85,11 +82,8 @@ namespace Discord
         public static void NotEqual(Optional<ulong?> obj, ulong value, string name, string msg = null) { if (obj.IsSpecified && obj.Value == value) throw CreateNotEqualException(name, msg, value); }
 
         private static ArgumentException CreateNotEqualException<T>(string name, string msg, T value)
-        {
-            if (msg == null) return new ArgumentException($"Value may not be equal to {value}", name);
-            else return new ArgumentException(msg, name);
-        }
-
+            => new ArgumentException(message: msg ?? $"Value may not be equal to {value}", paramName: name);
+        
         public static void AtLeast(sbyte obj, sbyte value, string name, string msg = null) { if (obj < value) throw CreateAtLeastException(name, msg, value); }
         public static void AtLeast(byte obj, byte value, string name, string msg = null) { if (obj < value) throw CreateAtLeastException(name, msg, value); }
         public static void AtLeast(short obj, short value, string name, string msg = null) { if (obj < value) throw CreateAtLeastException(name, msg, value); }
@@ -108,10 +102,7 @@ namespace Discord
         public static void AtLeast(Optional<ulong> obj, ulong value, string name, string msg = null) { if (obj.IsSpecified && obj.Value < value) throw CreateAtLeastException(name, msg, value); }
 
         private static ArgumentException CreateAtLeastException<T>(string name, string msg, T value)
-        {
-            if (msg == null) return new ArgumentException($"Value must be at least {value}", name);
-            else return new ArgumentException(msg, name);
-        }
+            => new ArgumentException(message: msg ?? $"Value must be at least {value}", paramName: name);
 
         public static void GreaterThan(sbyte obj, sbyte value, string name, string msg = null) { if (obj <= value) throw CreateGreaterThanException(name, msg, value); }
         public static void GreaterThan(byte obj, byte value, string name, string msg = null) { if (obj <= value) throw CreateGreaterThanException(name, msg, value); }
@@ -131,10 +122,7 @@ namespace Discord
         public static void GreaterThan(Optional<ulong> obj, ulong value, string name, string msg = null) { if (obj.IsSpecified && obj.Value <= value) throw CreateGreaterThanException(name, msg, value); }
 
         private static ArgumentException CreateGreaterThanException<T>(string name, string msg, T value)
-        {
-            if (msg == null) return new ArgumentException($"Value must be greater than {value}", name);
-            else return new ArgumentException(msg, name);
-        }
+            => new ArgumentException(message: msg ?? $"Value must be greater than {value}", paramName: name);
 
         public static void AtMost(sbyte obj, sbyte value, string name, string msg = null) { if (obj > value) throw CreateAtMostException(name, msg, value); }
         public static void AtMost(byte obj, byte value, string name, string msg = null) { if (obj > value) throw CreateAtMostException(name, msg, value); }
@@ -154,10 +142,7 @@ namespace Discord
         public static void AtMost(Optional<ulong> obj, ulong value, string name, string msg = null) { if (obj.IsSpecified && obj.Value > value) throw CreateAtMostException(name, msg, value); }
 
         private static ArgumentException CreateAtMostException<T>(string name, string msg, T value)
-        {
-            if (msg == null) return new ArgumentException($"Value must be at most {value}", name);
-            else return new ArgumentException(msg, name);
-        }
+            => new ArgumentException(message: msg ?? $"Value must be at most {value}", paramName: name);
 
         public static void LessThan(sbyte obj, sbyte value, string name, string msg = null) { if (obj >= value) throw CreateLessThanException(name, msg, value); }
         public static void LessThan(byte obj, byte value, string name, string msg = null) { if (obj >= value) throw CreateLessThanException(name, msg, value); }
@@ -177,10 +162,7 @@ namespace Discord
         public static void LessThan(Optional<ulong> obj, ulong value, string name, string msg = null) { if (obj.IsSpecified && obj.Value >= value) throw CreateLessThanException(name, msg, value); }
 
         private static ArgumentException CreateLessThanException<T>(string name, string msg, T value)
-        {
-            if (msg == null) return new ArgumentException($"Value must be less than {value}", name);
-            else return new ArgumentException(msg, name);
-        }
+            => new ArgumentException(message: msg ?? $"Value must be less than {value}", paramName: name);
 
         // Bulk Delete
         public static void YoungerThanTwoWeeks(ulong[] collection, string name)
@@ -198,7 +180,7 @@ namespace Discord
             for (var i = 0; i < roles.Length; i++)
             {
                 if (roles[i] == guildId)
-                    throw new ArgumentException("The everyone role cannot be assigned to a user", name);
+                    throw new ArgumentException(message: "The everyone role cannot be assigned to a user", paramName: name);
             }
         }
     }

src/Discord.Net.Core/Utils/TokenUtils.cs

@@ -19,7 +19,7 @@ namespace Discord
         {
             // A Null or WhiteSpace token of any type is invalid.
             if (string.IsNullOrWhiteSpace(token))
-                throw new ArgumentNullException("A token cannot be null, empty, or contain only whitespace.", nameof(token));
+                throw new ArgumentNullException(paramName: nameof(token), message: "A token cannot be null, empty, or contain only whitespace.");
 
             switch (tokenType)
             {
@@ -34,11 +34,11 @@ namespace Discord
                     // this value was determined by referencing examples in the discord documentation, and by comparing with
                     // pre-existing tokens
                     if (token.Length < 59)
-                        throw new ArgumentException("A Bot token must be at least 59 characters in length.", nameof(token));
+                        throw new ArgumentException(message: "A Bot token must be at least 59 characters in length.", paramName: nameof(token));
                     break;
                 default:
                     // All unrecognized TokenTypes (including User tokens) are considered to be invalid.
-                    throw new ArgumentException("Unrecognized TokenType.", nameof(token));
+                    throw new ArgumentException(message: "Unrecognized TokenType.", paramName: nameof(token));
             }
         }
 

src/Discord.Net.Rest/DiscordRestApiClient.cs

@@ -78,7 +78,7 @@ namespace Discord.API
                 case TokenType.Bearer:
                     return $"Bearer {token}";
                 default:
-                    throw new ArgumentException("Unknown OAuth token type", nameof(tokenType));
+                    throw new ArgumentException(message: "Unknown OAuth token type", paramName: nameof(tokenType));
             }
         }
         internal virtual void Dispose(bool disposing)
@@ -473,7 +473,7 @@ namespace Discord.API
                 Preconditions.NotNullOrEmpty(args.Content, nameof(args.Content));
 
             if (args.Content?.Length > DiscordConfig.MaxMessageSize)
-                throw new ArgumentException($"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.", nameof(args.Content));
+                throw new ArgumentException(message: $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.", paramName: nameof(args.Content));
             options = RequestOptions.CreateOrClone(options);
 
             var ids = new BucketIds(channelId: channelId);
@@ -490,7 +490,7 @@ namespace Discord.API
                 Preconditions.NotNullOrEmpty(args.Content, nameof(args.Content));
 
             if (args.Content?.Length > DiscordConfig.MaxMessageSize)
-                throw new ArgumentException($"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.", nameof(args.Content));
+                throw new ArgumentException(message: $"Message content is too long, length must be less or equal to {DiscordConfig.MaxMessageSize}.", paramName: nameof(args.Content));
             options = RequestOptions.CreateOrClone(options);
 
             return await SendJsonAsync<Message>("POST", () => $"webhooks/{webhookId}/{AuthToken}?wait=true", args, new BucketIds(), clientBucket: ClientBucketType.SendEdit, options: options).ConfigureAwait(false);

src/Discord.Net.Rest/Entities/Guilds/GuildHelper.cs

@@ -147,7 +147,7 @@ namespace Discord.Rest
         public static async Task<RestTextChannel> CreateTextChannelAsync(IGuild guild, BaseDiscordClient client,
             string name, RequestOptions options, Action<TextChannelProperties> func = null)
         {
-            if (name == null) throw new ArgumentNullException(nameof(name));
+            if (name == null) throw new ArgumentNullException(paramName: nameof(name));
 
             var props = new TextChannelProperties();
             func?.Invoke(props);
@@ -164,7 +164,7 @@ namespace Discord.Rest
         public static async Task<RestVoiceChannel> CreateVoiceChannelAsync(IGuild guild, BaseDiscordClient client,
             string name, RequestOptions options, Action<VoiceChannelProperties> func = null)
         {
-            if (name == null) throw new ArgumentNullException(nameof(name));
+            if (name == null) throw new ArgumentNullException(paramName: nameof(name));
 
             var props = new VoiceChannelProperties();
             func?.Invoke(props);
@@ -181,7 +181,7 @@ namespace Discord.Rest
         public static async Task<RestCategoryChannel> CreateCategoryChannelAsync(IGuild guild, BaseDiscordClient client,
             string name, RequestOptions options)
         {
-            if (name == null) throw new ArgumentNullException(nameof(name));
+            if (name == null) throw new ArgumentNullException(paramName: nameof(name));
 
             var args = new CreateGuildChannelParams(name, ChannelType.Category);
             var model = await client.ApiClient.CreateGuildChannelAsync(guild.Id, args, options).ConfigureAwait(false);
@@ -221,7 +221,7 @@ namespace Discord.Rest
         public static async Task<RestRole> CreateRoleAsync(IGuild guild, BaseDiscordClient client,
             string name, GuildPermissions? permissions, Color? color, bool isHoisted, RequestOptions options)
         {
-            if (name == null) throw new ArgumentNullException(nameof(name));
+            if (name == null) throw new ArgumentNullException(paramName: nameof(name));
 
             var model = await client.ApiClient.CreateGuildRoleAsync(guild.Id, options).ConfigureAwait(false);
             var role = RestRole.Create(client, guild, model);
@@ -356,7 +356,7 @@ namespace Discord.Rest
         public static async Task<GuildEmote> ModifyEmoteAsync(IGuild guild, BaseDiscordClient client, ulong id, Action<EmoteProperties> func, 
             RequestOptions options)
         {
-            if (func == null) throw new ArgumentNullException(nameof(func));
+            if (func == null) throw new ArgumentNullException(paramName: nameof(func));
 
             var props = new EmoteProperties();
             func(props);