Escape control characters.

2 files changed, 36 insertions, 13 deletions

diff --git a/src/main.rs b/src/main.rs
index 0cc9ad4..3663052 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -21,7 +21,7 @@ fn line_offset(stdin: &mut Reader, line: &Rope, col: u16) -> Result<usize, Box<d
             return Ok(i);
         }
         let c = line.byte(i);
-        if c > 127 {
+        if !(c == b'\t' || b' ' <= c && c <= b'~') {
             break;
         }
         if n == col {
@@ -231,12 +231,12 @@ impl State {
     }
 
     fn keypress(&mut self, key: Key) -> Result<bool, Box<dyn Error>> {
-        const CTRL_Q: char = (b'Q' - b'@') as char;
-        const CTRL_S: char = (b'S' - b'@') as char;
-        const CTRL_Y: char = (b'Y' - b'@') as char;
-        const CTRL_Z: char = (b'Z' - b'@') as char;
-        const BACKSPACE: char = (b'H' - b'@') as char;
-        const OTHER_BACKSPACE: char = '\x7f';
+        const CTRL_Q: char = (b'Q' ^ b'@') as char;
+        const CTRL_S: char = (b'S' ^ b'@') as char;
+        const CTRL_Y: char = (b'Y' ^ b'@') as char;
+        const CTRL_Z: char = (b'Z' ^ b'@') as char;
+        const BACKSPACE: char = (b'H' ^ b'@') as char;
+        const OTHER_BACKSPACE: char = (b'?' ^ b'@') as char;
 
         let inserting = self.inserting;
         self.inserting = false;
@@ -448,7 +448,7 @@ impl State {
             }
             Key::Char(CTRL_S) => {
                 let mut f = File::create(&self.path)?;
-                self.buf.print(&mut f)?;
+                self.buf.write(&mut f)?;
                 f.sync_all()?;
             }
             Key::Char(CTRL_Z) => {
@@ -546,15 +546,15 @@ impl State {
                     .line_start(self.row_start + usize::from(self.cursor_row))
                     + self.line_offset;
                 let mut buf = [0; 4];
-                let s = c.encode_utf8(&mut buf);
+                let r = Rope::new(c.encode_utf8(&mut buf));
                 self.buf = self
                     .buf
                     .slice(0, offset)
-                    .concat(&Rope::new(s))
+                    .concat(&r)
                     .concat(&self.buf.slice(offset, self.buf.len()));
-                self.line_offset += s.len();
+                self.line_offset += r.len();
                 self.need_repaint_line = true;
-                stdout().write_all(s.as_bytes())?;
+                r.print(&mut stdout())?;
                 stdout().flush()?;
             }
         }
diff --git a/src/rope.rs b/src/rope.rs
index ab9a7bc..ec25f61 100644
--- a/src/rope.rs
+++ b/src/rope.rs
@@ -342,7 +342,16 @@ impl Rope {
     pub fn print(&self, w: &mut dyn Write) -> Result<(), std::io::Error> {
         match self {
             Rope(Node::Leaf(l)) => {
-                w.write_all(l.buf().as_bytes())?;
+                for c in l.buf().chars() {
+                    if c < ' ' || c == '\x7f' {
+                        let b = u8::try_from(c).expect("c should be less than \\x7f");
+                        write!(w, "\x1b[36m^{}\x1b[m", char::from(b ^ 0x40))?;
+                    } else if '\u{80}' <= c && c <= '\u{9f}' {
+                        write!(w, "\x1b[36m<{:x}>\x1b[m", u32::from(c))?;
+                    } else {
+                        write!(w, "{}", c)?;
+                    }
+                }
                 Ok(())
             }
             Rope(Node::Branch(b)) => {
@@ -354,6 +363,20 @@ impl Rope {
         }
     }
 
+    pub fn write(&self, w: &mut dyn Write) -> Result<(), std::io::Error> {
+        match self {
+            Rope(Node::Leaf(l)) => {
+                w.write_all(l.buf().as_bytes())?;
+            }
+            Rope(Node::Branch(b)) => {
+                for c in b.children.iter() {
+                    c.write(w)?;
+                }
+            }
+        }
+        Ok(())
+    }
+
     pub fn slice(&self, start: usize, end: usize) -> Rope {
         if start > self.len() {
             panic!(