replace MessageSender interfaces with Session

channel.go

@@ -251,7 +251,7 @@ func (c *Channel) CopyOverTo(other interface{}) (err error) {
 }
 
 // SendMsgString same as SendMsg, however this only takes the message content (string) as a argument for the message
-func (c *Channel) SendMsgString(ctx context.Context, client MessageSender, content string) (msg *Message, err error) {
+func (c *Channel) SendMsgString(ctx context.Context, s Session, content string) (msg *Message, err error) {
 	if c.ID.IsZero() {
 		err = newErrorMissingSnowflake("snowflake ID not set for channel")
 		return
@@ -260,12 +260,12 @@ func (c *Channel) SendMsgString(ctx context.Context, client MessageSender, conte
 		Content: content,
 	}
 
-	msg, err = client.CreateMessage(ctx, c.ID, params)
+	msg, err = s.Channel(c.ID).WithContext(ctx).CreateMessage(params)
 	return
 }
 
 // SendMsg sends a message to a channel
-func (c *Channel) SendMsg(ctx context.Context, client MessageSender, message *Message) (msg *Message, err error) {
+func (c *Channel) SendMsg(ctx context.Context, s Session, message *Message) (msg *Message, err error) {
 	if c.ID.IsZero() {
 		err = newErrorMissingSnowflake("snowflake ID not set for channel")
 		return
@@ -286,7 +286,7 @@ func (c *Channel) SendMsg(ctx context.Context, client MessageSender, message *Me
 		params.Embed = message.Embeds[0]
 	}
 
-	msg, err = client.CreateMessage(ctx, c.ID, params)
+	msg, err = s.Channel(c.ID).WithContext(ctx).CreateMessage(params)
 	return
 }
 

message.go

@@ -254,13 +254,8 @@ func (m *Message) CopyOverTo(other interface{}) (err error) {
 	return
 }
 
-// MessageSender is an interface which only holds the method needed for creating a channel message
-type MessageSender interface {
-	CreateMessage(ctx context.Context, channelID Snowflake, params *CreateMessageParams, flags ...Flag) (ret *Message, err error)
-}
-
 // Send sends this message to discord.
-func (m *Message) Send(ctx context.Context, client MessageSender, flags ...Flag) (msg *Message, err error) {
+func (m *Message) Send(ctx context.Context, s Session, flags ...Flag) (msg *Message, err error) {
 	nonce := fmt.Sprint(m.Nonce)
 	if len(nonce) > 25 {
 		return nil, errors.New("nonce can not be more than 25 characters")
@@ -280,7 +275,7 @@ func (m *Message) Send(ctx context.Context, client MessageSender, flags ...Flag)
 	}
 	channelID := m.ChannelID
 
-	msg, err = client.CreateMessage(ctx, channelID, params, flags...)
+	msg, err = s.Channel(channelID).WithContext(ctx).CreateMessage(params, flags...)
 	return
 }