Merge pull request #280 from Droid00000/crosspost

Add crossposts.

lib/discordrb/api/channel.rb

@@ -142,6 +142,18 @@ def delete_message(token, channel_id, message_id, reason = nil)
     )
   end
 
+  # Crosspost a message
+  # https://discord.com/developers/docs/resources/message#crosspost-message
+  def crosspost_message(token, channel_id, message_id)
+    Discordrb::API.request(
+      :channels_cid_messages_mid,
+      channel_id,
+      :post,
+      "#{Discordrb::API.api_base}/channels/#{channel_id}/messages/#{message_id}/crosspost",
+      Authorization: token
+    )
+  end
+
   # Delete messages in bulk
   # https://discord.com/developers/docs/resources/channel#bulk-delete-messages
   def bulk_delete_messages(token, channel_id, messages = [], reason = nil)

lib/discordrb/data/message.rb

@@ -224,6 +224,12 @@ def unpin(reason = nil)
       nil
     end
 
+    # Crossposts a message in a news channel.
+    def crosspost
+      response = API::Channel.crosspost_message(@bot.token, @channel.id, @id)
+      Message.new(JSON.parse(response), @bot)
+    end
+
     # Add an {Await} for a message with the same user and channel.
     # @see Bot#add_await
     # @deprecated Will be changed to blocking behavior in v4.0. Use {#await!} instead.