feature: Add support for spoiler formatting & attachments (#1255)

Resolves #1216.

* Add support for spoiler formatting

* Implement support for sending message attachments that are spoilers

* use consistent naming

* update docstring for new isSpoiler param

* move extension method to be under core project, make spoiler prefix a const

* typo fix

* update missing xmldocs

* move SpoilerPrefix const outside of interface

* Add isSpoiler support to webhook client

adds the isSpoiler field to uploading files with a webhook, which will only
insert "SPOILER_" to the start of the filename. This does not include other
fields in the payload, as this is not in the documentation, and was not observed
like in the regular client

src/Discord.Net.Core/Entities/Channels/IMessageChannel.cs

@@ -54,11 +54,12 @@ namespace Discord
         /// <param name="isTTS">Whether the message should be read aloud by Discord or not.</param>
         /// <param name="embed">The <see cref="Discord.EmbedType.Rich" /> <see cref="Embed" /> to be sent.</param>
         /// <param name="options">The options to be used when sending the request.</param>
+        /// <param name="isSpoiler">Whether the message attachment should be hidden as a spoiler.</param>
         /// <returns>
         ///     A task that represents an asynchronous send operation for delivering the message. The task result
         ///     contains the sent message.
         /// </returns>
-        Task<IUserMessage> SendFileAsync(string filePath, string text = null, bool isTTS = false, Embed embed = null, RequestOptions options = null);
+        Task<IUserMessage> SendFileAsync(string filePath, string text = null, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false);
         /// <summary>
         ///     Sends a file to this message channel with an optional caption.
         /// </summary>
@@ -82,11 +83,12 @@ namespace Discord
         /// <param name="isTTS">Whether the message should be read aloud by Discord or not.</param>
         /// <param name="embed">The <see cref="Discord.EmbedType.Rich"/> <see cref="Embed"/> to be sent.</param>
         /// <param name="options">The options to be used when sending the request.</param>
+        /// <param name="isSpoiler">Whether the message attachment should be hidden as a spoiler.</param>
         /// <returns>
         ///     A task that represents an asynchronous send operation for delivering the message. The task result
         ///     contains the sent message.
         /// </returns>
-        Task<IUserMessage> SendFileAsync(Stream stream, string filename, string text = null, bool isTTS = false, Embed embed = null, RequestOptions options = null);
+        Task<IUserMessage> SendFileAsync(Stream stream, string filename, string text = null, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false);
 
         /// <summary>
         ///     Gets a message from this message channel.

src/Discord.Net.Core/Extensions/AttachmentExtensions.cs

@@ -0,0 +1,15 @@
+namespace Discord
+{
+    public static class AttachmentExtensions
+    {
+        /// <summary>
+        ///     The prefix applied to files to indicate that it is a spoiler.
+        /// </summary>
+        public const string SpoilerPrefix = "SPOILER_";
+        /// <summary>
+        ///     Gets whether the message's attachments are spoilers or not.
+        /// </summary>
+        public static bool IsSpoiler(this IAttachment attachment)
+            => attachment.Filename.StartsWith(SpoilerPrefix);
+    }
+}

src/Discord.Net.Core/Format.cs

@@ -4,7 +4,7 @@ namespace Discord
     public static class Format
     {
         // Characters which need escaping
-        private static readonly string[] SensitiveCharacters = { "\\", "*", "_", "~", "`" };
+        private static readonly string[] SensitiveCharacters = { "\\", "*", "_", "~", "`", "|" };
 
         /// <summary> Returns a markdown-formatted string with bold formatting. </summary>
         public static string Bold(string text) => $"**{text}**";
@@ -14,6 +14,8 @@ namespace Discord
         public static string Underline(string text) => $"__{text}__";
         /// <summary> Returns a markdown-formatted string with strikethrough formatting. </summary>
         public static string Strikethrough(string text) => $"~~{text}~~";
+        /// <summary> Returns a string with spoiler formatting. </summary>
+        public static string Spoiler(string text) => $"||{text}||";
         /// <summary> Returns a markdown-formatted URL. Only works in <see cref="EmbedBuilder"/> descriptions and fields. </summary>
         public static string Url(string text, string url) => $"[{text}]({url})";
         /// <summary> Escapes a URL so that a preview is not generated. </summary>

src/Discord.Net.Rest/API/Rest/UploadFileParams.cs

@@ -19,6 +19,7 @@ namespace Discord.API.Rest
         public Optional<string> Nonce { get; set; }
         public Optional<bool> IsTTS { get; set; }
         public Optional<Embed> Embed { get; set; }
+        public bool IsSpoiler { get; set; } = false;
 
         public UploadFileParams(Stream file)
         {
@@ -28,7 +29,10 @@ namespace Discord.API.Rest
         public IReadOnlyDictionary<string, object> ToDictionary()
         {
             var d = new Dictionary<string, object>();
-            d["file"] = new MultipartFile(File, Filename.GetValueOrDefault("unknown.dat"));
+            var filename = Filename.GetValueOrDefault("unknown.dat");
+            if (IsSpoiler && !filename.StartsWith(AttachmentExtensions.SpoilerPrefix))
+                filename = filename.Insert(0, AttachmentExtensions.SpoilerPrefix);
+            d["file"] = new MultipartFile(File, filename);
 
             var payload = new Dictionary<string, object>();
             if (Content.IsSpecified)
@@ -39,6 +43,8 @@ namespace Discord.API.Rest
                 payload["nonce"] = Nonce.Value;
             if (Embed.IsSpecified)
                 payload["embed"] = Embed.Value;
+            if (IsSpoiler)
+                payload["hasSpoiler"] = IsSpoiler.ToString();
 
             var json = new StringBuilder();
             using (var text = new StringWriter(json))

src/Discord.Net.Rest/API/Rest/UploadWebhookFileParams.cs

@@ -22,6 +22,8 @@ namespace Discord.API.Rest
         public Optional<string> AvatarUrl { get; set; }
         public Optional<Embed[]> Embeds { get; set; }
 
+        public bool IsSpoiler { get; set; } = false;
+
         public UploadWebhookFileParams(Stream file)
         {
             File = file;
@@ -30,7 +32,11 @@ namespace Discord.API.Rest
         public IReadOnlyDictionary<string, object> ToDictionary()
         {
             var d = new Dictionary<string, object>();
-            d["file"] = new MultipartFile(File, Filename.GetValueOrDefault("unknown.dat"));
+            var filename = Filename.GetValueOrDefault("unknown.dat");
+            if (IsSpoiler && !filename.StartsWith(AttachmentExtensions.SpoilerPrefix))
+                filename = filename.Insert(0, AttachmentExtensions.SpoilerPrefix);
+
+            d["file"] = new MultipartFile(File, filename);
 
             var payload = new Dictionary<string, object>();
             if (Content.IsSpecified)

src/Discord.Net.Rest/Entities/Channels/ChannelHelper.cs

@@ -199,18 +199,18 @@ namespace Discord.Rest
         /// <exception cref="IOException">An I/O error occurred while opening the file.</exception>
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
         public static async Task<RestUserMessage> SendFileAsync(IMessageChannel channel, BaseDiscordClient client,
-            string filePath, string text, bool isTTS, Embed embed, RequestOptions options)
+            string filePath, string text, bool isTTS, Embed embed, RequestOptions options, bool isSpoiler)
         {
             string filename = Path.GetFileName(filePath);
             using (var file = File.OpenRead(filePath))
-                return await SendFileAsync(channel, client, file, filename, text, isTTS, embed, options).ConfigureAwait(false);
+                return await SendFileAsync(channel, client, file, filename, text, isTTS, embed, options, isSpoiler).ConfigureAwait(false);
         }
 
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
         public static async Task<RestUserMessage> SendFileAsync(IMessageChannel channel, BaseDiscordClient client,
-            Stream stream, string filename, string text, bool isTTS, Embed embed, RequestOptions options)
+            Stream stream, string filename, string text, bool isTTS, Embed embed, RequestOptions options, bool isSpoiler)
         {
-            var args = new UploadFileParams(stream) { Filename = filename, Content = text, IsTTS = isTTS, Embed = embed != null ? embed.ToModel() : Optional<API.Embed>.Unspecified };
+            var args = new UploadFileParams(stream) { Filename = filename, Content = text, IsTTS = isTTS, Embed = embed != null ? embed.ToModel() : Optional<API.Embed>.Unspecified, IsSpoiler = isSpoiler };
             var model = await client.ApiClient.UploadFileAsync(channel.Id, args, options).ConfigureAwait(false);
             return RestUserMessage.Create(client, channel, client.CurrentUser, model);
         }

src/Discord.Net.Rest/Entities/Channels/IRestMessageChannel.cs

@@ -42,12 +42,12 @@ namespace Discord.Rest
         ///     A task that represents an asynchronous send operation for delivering the message. The task result
         ///     contains the sent message.
         /// </returns>
-        new Task<RestUserMessage> SendFileAsync(string filePath, string text = null, bool isTTS = false, Embed embed = null, RequestOptions options = null);
+        new Task<RestUserMessage> SendFileAsync(string filePath, string text = null, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false);
         /// <summary>
         ///     Sends a file to this message channel with an optional caption.
         /// </summary>
         /// <remarks>
-        ///     This method follows the same behavior as described in <see cref="IMessageChannel.SendFileAsync(Stream, string, string, bool, Embed, RequestOptions)"/>.
+        ///     This method follows the same behavior as described in <see cref="IMessageChannel.SendFileAsync(Stream, string, string, bool, Embed, RequestOptions, bool)"/>.
         ///     Please visit its documentation for more details on this method.
         /// </remarks>
         /// <param name="stream">The <see cref="Stream" /> of the file to be sent.</param>
@@ -60,7 +60,7 @@ namespace Discord.Rest
         ///     A task that represents an asynchronous send operation for delivering the message. The task result
         ///     contains the sent message.
         /// </returns>
-        new Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text = null, bool isTTS = false, Embed embed = null, RequestOptions options = null);
+        new Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text = null, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false);
 
         /// <summary>
         ///     Gets a message from this message channel.

src/Discord.Net.Rest/Entities/Channels/RestDMChannel.cs

@@ -121,12 +121,12 @@ namespace Discord.Rest
         /// <exception cref="NotSupportedException"><paramref name="filePath" /> is in an invalid format.</exception>
         /// <exception cref="IOException">An I/O error occurred while opening the file.</exception>
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null)
-            => ChannelHelper.SendFileAsync(this, Discord, filePath, text, isTTS, embed, options);
+        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false)
+            => ChannelHelper.SendFileAsync(this, Discord, filePath, text, isTTS, embed, options, isSpoiler);
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null)
-            => ChannelHelper.SendFileAsync(this, Discord, stream, filename, text, isTTS, embed, options);
+        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false)
+            => ChannelHelper.SendFileAsync(this, Discord, stream, filename, text, isTTS, embed, options, isSpoiler);
 
         /// <inheritdoc />
         public Task DeleteMessageAsync(ulong messageId, RequestOptions options = null)
@@ -200,11 +200,11 @@ namespace Discord.Rest
         async Task<IReadOnlyCollection<IMessage>> IMessageChannel.GetPinnedMessagesAsync(RequestOptions options)
             => await GetPinnedMessagesAsync(options).ConfigureAwait(false);
         /// <inheritdoc />
-        async Task<IUserMessage> IMessageChannel.SendFileAsync(string filePath, string text, bool isTTS, Embed embed, RequestOptions options)
-            => await SendFileAsync(filePath, text, isTTS, embed, options).ConfigureAwait(false);
+        async Task<IUserMessage> IMessageChannel.SendFileAsync(string filePath, string text, bool isTTS, Embed embed, RequestOptions options, bool isSpoiler)
+            => await SendFileAsync(filePath, text, isTTS, embed, options, isSpoiler).ConfigureAwait(false);
         /// <inheritdoc />
-        async Task<IUserMessage> IMessageChannel.SendFileAsync(Stream stream, string filename, string text, bool isTTS, Embed embed, RequestOptions options)
-            => await SendFileAsync(stream, filename, text, isTTS, embed, options).ConfigureAwait(false);
+        async Task<IUserMessage> IMessageChannel.SendFileAsync(Stream stream, string filename, string text, bool isTTS, Embed embed, RequestOptions options, bool isSpoiler)
+            => await SendFileAsync(stream, filename, text, isTTS, embed, options, isSpoiler).ConfigureAwait(false);
         /// <inheritdoc />
         async Task<IUserMessage> IMessageChannel.SendMessageAsync(string text, bool isTTS, Embed embed, RequestOptions options)
             => await SendMessageAsync(text, isTTS, embed, options).ConfigureAwait(false);

src/Discord.Net.Rest/Entities/Channels/RestGroupChannel.cs

@@ -123,12 +123,12 @@ namespace Discord.Rest
         /// <exception cref="NotSupportedException"><paramref name="filePath" /> is in an invalid format.</exception>
         /// <exception cref="IOException">An I/O error occurred while opening the file.</exception>
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null)
-            => ChannelHelper.SendFileAsync(this, Discord, filePath, text, isTTS, embed, options);
+        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false)
+            => ChannelHelper.SendFileAsync(this, Discord, filePath, text, isTTS, embed, options, isSpoiler);
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null)
-            => ChannelHelper.SendFileAsync(this, Discord, stream, filename, text, isTTS, embed, options);
+        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false)
+            => ChannelHelper.SendFileAsync(this, Discord, stream, filename, text, isTTS, embed, options, isSpoiler);
 
         /// <inheritdoc />
         public Task TriggerTypingAsync(RequestOptions options = null)
@@ -178,11 +178,11 @@ namespace Discord.Rest
         async Task<IReadOnlyCollection<IMessage>> IMessageChannel.GetPinnedMessagesAsync(RequestOptions options)
             => await GetPinnedMessagesAsync(options).ConfigureAwait(false);
 
-        async Task<IUserMessage> IMessageChannel.SendFileAsync(string filePath, string text, bool isTTS, Embed embed, RequestOptions options)
-            => await SendFileAsync(filePath, text, isTTS, embed, options).ConfigureAwait(false);
+        async Task<IUserMessage> IMessageChannel.SendFileAsync(string filePath, string text, bool isTTS, Embed embed, RequestOptions options, bool isSpoiler)
+            => await SendFileAsync(filePath, text, isTTS, embed, options, isSpoiler).ConfigureAwait(false);
 
-        async Task<IUserMessage> IMessageChannel.SendFileAsync(Stream stream, string filename, string text, bool isTTS, Embed embed, RequestOptions options)
-            => await SendFileAsync(stream, filename, text, isTTS, embed, options).ConfigureAwait(false);
+        async Task<IUserMessage> IMessageChannel.SendFileAsync(Stream stream, string filename, string text, bool isTTS, Embed embed, RequestOptions options, bool isSpoiler)
+            => await SendFileAsync(stream, filename, text, isTTS, embed, options, isSpoiler).ConfigureAwait(false);
         async Task<IUserMessage> IMessageChannel.SendMessageAsync(string text, bool isTTS, Embed embed, RequestOptions options)
             => await SendMessageAsync(text, isTTS, embed, options).ConfigureAwait(false);
 

src/Discord.Net.Rest/Entities/Channels/RestTextChannel.cs

@@ -129,13 +129,13 @@ namespace Discord.Rest
         /// <exception cref="NotSupportedException"><paramref name="filePath" /> is in an invalid format.</exception>
         /// <exception cref="IOException">An I/O error occurred while opening the file.</exception>
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null)
-            => ChannelHelper.SendFileAsync(this, Discord, filePath, text, isTTS, embed, options);
+        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false)
+            => ChannelHelper.SendFileAsync(this, Discord, filePath, text, isTTS, embed, options, isSpoiler);
 
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null)
-            => ChannelHelper.SendFileAsync(this, Discord, stream, filename, text, isTTS, embed, options);
+        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false)
+            => ChannelHelper.SendFileAsync(this, Discord, stream, filename, text, isTTS, embed, options, isSpoiler);
 
         /// <inheritdoc />
         public Task DeleteMessageAsync(ulong messageId, RequestOptions options = null)
@@ -266,12 +266,12 @@ namespace Discord.Rest
             => await GetPinnedMessagesAsync(options).ConfigureAwait(false);
 
         /// <inheritdoc />
-        async Task<IUserMessage> IMessageChannel.SendFileAsync(string filePath, string text, bool isTTS, Embed embed, RequestOptions options)
-            => await SendFileAsync(filePath, text, isTTS, embed, options).ConfigureAwait(false);
+        async Task<IUserMessage> IMessageChannel.SendFileAsync(string filePath, string text, bool isTTS, Embed embed, RequestOptions options, bool isSpoiler)
+            => await SendFileAsync(filePath, text, isTTS, embed, options, isSpoiler).ConfigureAwait(false);
 
         /// <inheritdoc />
-        async Task<IUserMessage> IMessageChannel.SendFileAsync(Stream stream, string filename, string text, bool isTTS, Embed embed, RequestOptions options)
-            => await SendFileAsync(stream, filename, text, isTTS, embed, options).ConfigureAwait(false);
+        async Task<IUserMessage> IMessageChannel.SendFileAsync(Stream stream, string filename, string text, bool isTTS, Embed embed, RequestOptions options, bool isSpoiler)
+            => await SendFileAsync(stream, filename, text, isTTS, embed, options, isSpoiler).ConfigureAwait(false);
         /// <inheritdoc />
         async Task<IUserMessage> IMessageChannel.SendMessageAsync(string text, bool isTTS, Embed embed, RequestOptions options)
             => await SendMessageAsync(text, isTTS, embed, options).ConfigureAwait(false);

src/Discord.Net.WebSocket/Entities/Channels/ISocketMessageChannel.cs

@@ -38,7 +38,7 @@ namespace Discord.WebSocket
         ///     Sends a file to this message channel with an optional caption.
         /// </summary>
         /// <remarks>
-        ///     This method follows the same behavior as described in <see cref="IMessageChannel.SendFileAsync(string, string, bool, Embed, RequestOptions)"/>.
+        ///     This method follows the same behavior as described in <see cref="IMessageChannel.SendFileAsync(string, string, bool, Embed, RequestOptions, bool)"/>.
         ///     Please visit its documentation for more details on this method.
         /// </remarks>
         /// <param name="filePath">The file path of the file.</param>
@@ -46,11 +46,12 @@ namespace Discord.WebSocket
         /// <param name="isTTS">Whether the message should be read aloud by Discord or not.</param>
         /// <param name="embed">The <see cref="Discord.EmbedType.Rich" /> <see cref="Embed" /> to be sent.</param>
         /// <param name="options">The options to be used when sending the request.</param>
+        /// <param name="isSpoiler">Whether the message attachment should be hidden as a spoiler.</param>
         /// <returns>
         ///     A task that represents an asynchronous send operation for delivering the message. The task result
         ///     contains the sent message.
         /// </returns>
-        new Task<RestUserMessage> SendFileAsync(string filePath, string text = null, bool isTTS = false, Embed embed = null, RequestOptions options = null);
+        new Task<RestUserMessage> SendFileAsync(string filePath, string text = null, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false);
         /// <summary>
         ///     Sends a file to this message channel with an optional caption.
         /// </summary>
@@ -64,11 +65,12 @@ namespace Discord.WebSocket
         /// <param name="isTTS">Whether the message should be read aloud by Discord or not.</param>
         /// <param name="embed">The <see cref="Discord.EmbedType.Rich"/> <see cref="Embed"/> to be sent.</param>
         /// <param name="options">The options to be used when sending the request.</param>
+        /// <param name="isSpoiler">Whether the message attachment should be hidden as a spoiler.</param>
         /// <returns>
         ///     A task that represents an asynchronous send operation for delivering the message. The task result
         ///     contains the sent message.
         /// </returns>
-        new Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text = null, bool isTTS = false, Embed embed = null, RequestOptions options = null);
+        new Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text = null, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false);
 
         /// <summary>
         ///     Gets a cached message from this channel.

src/Discord.Net.WebSocket/Entities/Channels/SocketDMChannel.cs

@@ -139,12 +139,12 @@ namespace Discord.WebSocket
             => ChannelHelper.SendMessageAsync(this, Discord, text, isTTS, embed, options);
 
         /// <inheritdoc />
-        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null)
-            => ChannelHelper.SendFileAsync(this, Discord, filePath, text, isTTS, embed, options);
+        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false)
+            => ChannelHelper.SendFileAsync(this, Discord, filePath, text, isTTS, embed, options, isSpoiler);
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null)
-            => ChannelHelper.SendFileAsync(this, Discord, stream, filename, text, isTTS, embed, options);
+        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false)
+            => ChannelHelper.SendFileAsync(this, Discord, stream, filename, text, isTTS, embed, options, isSpoiler);
         /// <inheritdoc />
         public Task DeleteMessageAsync(ulong messageId, RequestOptions options = null)
             => ChannelHelper.DeleteMessageAsync(this, messageId, Discord, options);
@@ -229,11 +229,11 @@ namespace Discord.WebSocket
         async Task<IReadOnlyCollection<IMessage>> IMessageChannel.GetPinnedMessagesAsync(RequestOptions options)
             => await GetPinnedMessagesAsync(options).ConfigureAwait(false);
         /// <inheritdoc />
-        async Task<IUserMessage> IMessageChannel.SendFileAsync(string filePath, string text, bool isTTS, Embed embed, RequestOptions options)
-            => await SendFileAsync(filePath, text, isTTS, embed, options).ConfigureAwait(false);
+        async Task<IUserMessage> IMessageChannel.SendFileAsync(string filePath, string text, bool isTTS, Embed embed, RequestOptions options, bool isSpoiler)
+            => await SendFileAsync(filePath, text, isTTS, embed, options, isSpoiler).ConfigureAwait(false);
         /// <inheritdoc />
-        async Task<IUserMessage> IMessageChannel.SendFileAsync(Stream stream, string filename, string text, bool isTTS, Embed embed, RequestOptions options)
-            => await SendFileAsync(stream, filename, text, isTTS, embed, options).ConfigureAwait(false);
+        async Task<IUserMessage> IMessageChannel.SendFileAsync(Stream stream, string filename, string text, bool isTTS, Embed embed, RequestOptions options, bool isSpoiler)
+            => await SendFileAsync(stream, filename, text, isTTS, embed, options, isSpoiler).ConfigureAwait(false);
         /// <inheritdoc />
         async Task<IUserMessage> IMessageChannel.SendMessageAsync(string text, bool isTTS, Embed embed, RequestOptions options)
             => await SendMessageAsync(text, isTTS, embed, options).ConfigureAwait(false);

src/Discord.Net.WebSocket/Entities/Channels/SocketGroupChannel.cs

@@ -167,11 +167,11 @@ namespace Discord.WebSocket
             => ChannelHelper.SendMessageAsync(this, Discord, text, isTTS, embed, options);
 
         /// <inheritdoc />
-        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null)
-            => ChannelHelper.SendFileAsync(this, Discord, filePath, text, isTTS, embed, options);
+        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false)
+            => ChannelHelper.SendFileAsync(this, Discord, filePath, text, isTTS, embed, options, isSpoiler);
         /// <inheritdoc />
-        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null)
-            => ChannelHelper.SendFileAsync(this, Discord, stream, filename, text, isTTS, embed, options);
+        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false)
+            => ChannelHelper.SendFileAsync(this, Discord, stream, filename, text, isTTS, embed, options, isSpoiler);
 
         /// <inheritdoc />
         public Task DeleteMessageAsync(ulong messageId, RequestOptions options = null)
@@ -293,11 +293,11 @@ namespace Discord.WebSocket
             => await GetPinnedMessagesAsync(options).ConfigureAwait(false);
 
         /// <inheritdoc />
-        async Task<IUserMessage> IMessageChannel.SendFileAsync(string filePath, string text, bool isTTS, Embed embed, RequestOptions options)
-            => await SendFileAsync(filePath, text, isTTS, embed, options).ConfigureAwait(false);
+        async Task<IUserMessage> IMessageChannel.SendFileAsync(string filePath, string text, bool isTTS, Embed embed, RequestOptions options, bool isSpoiler)
+            => await SendFileAsync(filePath, text, isTTS, embed, options, isSpoiler).ConfigureAwait(false);
         /// <inheritdoc />
-        async Task<IUserMessage> IMessageChannel.SendFileAsync(Stream stream, string filename, string text, bool isTTS, Embed embed, RequestOptions options)
-            => await SendFileAsync(stream, filename, text, isTTS, embed, options).ConfigureAwait(false);
+        async Task<IUserMessage> IMessageChannel.SendFileAsync(Stream stream, string filename, string text, bool isTTS, Embed embed, RequestOptions options, bool isSpoiler)
+            => await SendFileAsync(stream, filename, text, isTTS, embed, options, isSpoiler).ConfigureAwait(false);
         /// <inheritdoc />
         async Task<IUserMessage> IMessageChannel.SendMessageAsync(string text, bool isTTS, Embed embed, RequestOptions options)
             => await SendMessageAsync(text, isTTS, embed, options).ConfigureAwait(false);

src/Discord.Net.WebSocket/Entities/Channels/SocketTextChannel.cs

@@ -165,13 +165,13 @@ namespace Discord.WebSocket
             => ChannelHelper.SendMessageAsync(this, Discord, text, isTTS, embed, options);
 
         /// <inheritdoc />
-        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null)
-            => ChannelHelper.SendFileAsync(this, Discord, filePath, text, isTTS, embed, options);
+        public Task<RestUserMessage> SendFileAsync(string filePath, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false)
+            => ChannelHelper.SendFileAsync(this, Discord, filePath, text, isTTS, embed, options, isSpoiler);
 
         /// <inheritdoc />
         /// <exception cref="ArgumentOutOfRangeException">Message content is too long, length must be less or equal to <see cref="DiscordConfig.MaxMessageSize"/>.</exception>
-        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null)
-            => ChannelHelper.SendFileAsync(this, Discord, stream, filename, text, isTTS, embed, options);
+        public Task<RestUserMessage> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false, Embed embed = null, RequestOptions options = null, bool isSpoiler = false)
+            => ChannelHelper.SendFileAsync(this, Discord, stream, filename, text, isTTS, embed, options, isSpoiler);
 
         /// <inheritdoc />
         public Task DeleteMessagesAsync(IEnumerable<IMessage> messages, RequestOptions options = null)
@@ -302,11 +302,11 @@ namespace Discord.WebSocket
             => await GetPinnedMessagesAsync(options).ConfigureAwait(false);
 
         /// <inheritdoc />
-        async Task<IUserMessage> IMessageChannel.SendFileAsync(string filePath, string text, bool isTTS, Embed embed, RequestOptions options)
-            => await SendFileAsync(filePath, text, isTTS, embed, options).ConfigureAwait(false);
+        async Task<IUserMessage> IMessageChannel.SendFileAsync(string filePath, string text, bool isTTS, Embed embed, RequestOptions options, bool isSpoiler)
+            => await SendFileAsync(filePath, text, isTTS, embed, options, isSpoiler).ConfigureAwait(false);
         /// <inheritdoc />
-        async Task<IUserMessage> IMessageChannel.SendFileAsync(Stream stream, string filename, string text, bool isTTS, Embed embed, RequestOptions options)
-            => await SendFileAsync(stream, filename, text, isTTS, embed, options).ConfigureAwait(false);
+        async Task<IUserMessage> IMessageChannel.SendFileAsync(Stream stream, string filename, string text, bool isTTS, Embed embed, RequestOptions options, bool isSpoiler)
+            => await SendFileAsync(stream, filename, text, isTTS, embed, options, isSpoiler).ConfigureAwait(false);
         /// <inheritdoc />
         async Task<IUserMessage> IMessageChannel.SendMessageAsync(string text, bool isTTS, Embed embed, RequestOptions options)
             => await SendMessageAsync(text, isTTS, embed, options).ConfigureAwait(false);

src/Discord.Net.Webhook/DiscordWebhookClient.cs

@@ -93,13 +93,13 @@ namespace Discord.Webhook
         /// <summary> Sends a message to the channel for this webhook with an attachment. </summary>
         /// <returns> Returns the ID of the created message. </returns>
         public Task<ulong> SendFileAsync(string filePath, string text, bool isTTS = false,
-            IEnumerable<Embed> embeds = null, string username = null, string avatarUrl = null, RequestOptions options = null)
-            => WebhookClientHelper.SendFileAsync(this, filePath, text, isTTS, embeds, username, avatarUrl, options);
+            IEnumerable<Embed> embeds = null, string username = null, string avatarUrl = null, RequestOptions options = null, bool isSpoiler = false)
+            => WebhookClientHelper.SendFileAsync(this, filePath, text, isTTS, embeds, username, avatarUrl, options, isSpoiler);
         /// <summary> Sends a message to the channel for this webhook with an attachment. </summary>
         /// <returns> Returns the ID of the created message. </returns>
         public Task<ulong> SendFileAsync(Stream stream, string filename, string text, bool isTTS = false,
-            IEnumerable<Embed> embeds = null, string username = null, string avatarUrl = null, RequestOptions options = null)
-            => WebhookClientHelper.SendFileAsync(this, stream, filename, text, isTTS, embeds, username, avatarUrl, options);
+            IEnumerable<Embed> embeds = null, string username = null, string avatarUrl = null, RequestOptions options = null, bool isSpoiler = false)
+            => WebhookClientHelper.SendFileAsync(this, stream, filename, text, isTTS, embeds, username, avatarUrl, options, isSpoiler);
 
         /// <summary> Modifies the properties of this webhook. </summary>
         public Task ModifyWebhookAsync(Action<WebhookProperties> func, RequestOptions options = null)

src/Discord.Net.Webhook/WebhookClientHelper.cs

@@ -35,16 +35,16 @@ namespace Discord.Webhook
             return model.Id;
         }
         public static async Task<ulong> SendFileAsync(DiscordWebhookClient client, string filePath, string text, bool isTTS, 
-            IEnumerable<Embed> embeds, string username, string avatarUrl, RequestOptions options)
+            IEnumerable<Embed> embeds, string username, string avatarUrl, RequestOptions options, bool isSpoiler)
         {
             string filename = Path.GetFileName(filePath);
             using (var file = File.OpenRead(filePath))
-                return await SendFileAsync(client, file, filename, text, isTTS, embeds, username, avatarUrl, options).ConfigureAwait(false);
+                return await SendFileAsync(client, file, filename, text, isTTS, embeds, username, avatarUrl, options, isSpoiler).ConfigureAwait(false);
         }
         public static async Task<ulong> SendFileAsync(DiscordWebhookClient client, Stream stream, string filename, string text, bool isTTS,
-            IEnumerable<Embed> embeds, string username, string avatarUrl, RequestOptions options)
+            IEnumerable<Embed> embeds, string username, string avatarUrl, RequestOptions options, bool isSpoiler)
         {
-            var args = new UploadWebhookFileParams(stream) { Filename = filename, Content = text, IsTTS = isTTS };
+            var args = new UploadWebhookFileParams(stream) { Filename = filename, Content = text, IsTTS = isTTS, IsSpoiler = isSpoiler };
             if (username != null)
                 args.Username = username;
             if (avatarUrl != null)