1 files changed, 10 insertions, 0 deletions

diff --git a/src/linebuf.rs b/src/linebuf.rs
index 15a8182..1d28549 100644
--- a/src/linebuf.rs
+++ b/src/linebuf.rs
@@ -4,6 +4,7 @@ use std::io::Write;
 pub struct LineBuf {
     pre: Vec<u8>,
     post: Vec<u8>,
+    dirty: bool,
 }
 
 #[allow(unused)]
@@ -12,14 +13,17 @@ impl LineBuf {
         Self {
             pre: Vec::new(),
             post: Vec::new(),
+            dirty: false,
         }
     }
 
     pub fn del_left(&mut self) -> Option<u8> {
+        self.dirty = true;
         self.pre.pop()
     }
 
     pub fn del_right(&mut self) -> Option<u8> {
+        self.dirty = true;
         self.post.pop()
     }
 
@@ -42,6 +46,7 @@ impl LineBuf {
     }
 
     pub fn add(&mut self, chr: u8) {
+        self.dirty = true;
         self.pre.push(chr);
     }
 
@@ -49,6 +54,10 @@ impl LineBuf {
         self.pre.is_empty() && self.post.is_empty()
     }
 
+    pub fn is_dirty(&self) -> bool {
+        self.dirty
+    }
+
     /// sets content all to the left
     pub fn set_content(&mut self, buf: Vec<u8>) {
         self.pre = buf;
@@ -60,6 +69,7 @@ impl LineBuf {
         while self.right() {}
         let mut buf = Vec::new();
         core::mem::swap(&mut self.pre, &mut buf);
+        self.dirty = false;
         buf
     }