Handle vi redo last command

src/keymap.rs

@@ -83,6 +83,7 @@ pub struct EditState {
     insert: bool, // vi only ?
     // numeric arguments: http://web.mit.edu/gnu/doc/html/rlman_1.html#SEC7
     num_args: i16,
+    last_cmd: Cmd, // vi only
 }
 
 #[derive(Debug, Clone, PartialEq)]
@@ -103,6 +104,7 @@ impl EditState {
             mode: config.edit_mode(),
             insert: true,
             num_args: 0,
+            last_cmd: Cmd::Noop,
         }
     }
 
@@ -274,6 +276,7 @@ impl EditState {
         let cmd = match key {
             KeyPress::Char('$') |
             KeyPress::End => Cmd::EndOfLine,
+            KeyPress::Char('.') => self.last_cmd.clone(), // vi-redo
             // TODO KeyPress::Char('%') => Cmd::???, Move to the corresponding opening/closing bracket
             KeyPress::Char('0') => Cmd::BeginningOfLine, // vi-zero: Vi move to the beginning of line.
             KeyPress::Char('^') => Cmd::BeginningOfLine, // vi-first-print TODO Move to the first non-blank character of line.
@@ -388,6 +391,9 @@ impl EditState {
             _ => self.common(key, n, true),
         };
         debug!(target: "rustyline", "Vi command: {:?}", cmd);
+        if key != KeyPress::Char('.') {
+            self.last_cmd = cmd.clone();
+        }
         Ok(cmd)
     }
 
@@ -406,6 +412,7 @@ impl EditState {
             _ => self.common(key, 1, true),
         };
         debug!(target: "rustyline", "Vi insert: {:?}", cmd);
+        self.last_cmd = cmd.clone();
         Ok(cmd)
     }