muc::History::disabled() and muc::Muc::without_history() disable legacy history on MUC join (#77)

parsers/ChangeLog

@@ -9,6 +9,8 @@ xxx
         - Presence::with_payload builds a payload into the presence (#79)
         - Message now has constructors for each type ; Message::new still builds a Chat type (#78)
         - Message::with_body builder method appends a body in a given language to the message (#78)
+        - muc::History::disabled method requests 0 maxchars history from MUC (#77)
+        - muc::Muc::without_history builder method requests 0 maxchars history from MUC (#77)
     * Breaking changes:
         - Removed the 'serde' feature. Add it directly by using 'jid'.
         `jid = { version = "*", features = ["serde"] }`.

parsers/src/muc/muc.rs

@@ -33,6 +33,11 @@ impl History {
         History::default()
     }
 
+    /// Don't request history from MUC
+    pub fn disabled() -> Self {
+        Self::new().with_maxchars(0)
+    }
+
     /// Set how many characters of history to send.
     pub fn with_maxchars(mut self, maxchars: u32) -> Self {
         self.maxchars = Some(maxchars);
@@ -89,6 +94,12 @@ impl Muc {
         self.history = Some(history);
         self
     }
+
+    /// Join a room without history.
+    pub fn without_history(mut self) -> Self {
+        self.history = Some(History::disabled());
+        self
+    }
 }
 
 #[cfg(test)]