Make publicly exported types implement Debug trait

It seems to have become common practice for publicly exported types in a
library to implement the Debug trait. Doing so potentially simplifies
trouble shooting in client code directly but it also is a requirement in
case said client code embeds such objects and wants the wrappers to
implement this trait. For a deeper discussion of this topic please refer
to rust-lang/rust#32054

To that end, this change adjust all publicly exported types to derive
from Debug. It also adds a crate wide lint enforcing this constraint.

src/async.rs

@@ -30,6 +30,7 @@ pub fn async_stdin() -> AsyncReader {
 ///
 /// This acts as any other stream, with the exception that reading from it won't block. Instead,
 /// the buffer will only be partially updated based on how much the internal buffer holds.
+#[derive(Debug)]
 pub struct AsyncReader {
     /// The underlying mpsc receiver.
     recv: mpsc::Receiver<io::Result<u8>>,

src/cursor.rs

@@ -29,7 +29,7 @@ derive_csi_sequence!("Save the cursor.", Save, "s");
 ///     print!("{}{}Stuff", termion::clear::All, termion::cursor::Goto(5, 3));
 /// }
 /// ```
-#[derive(Copy, Clone, PartialEq, Eq)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub struct Goto(pub u16, pub u16);
 
 impl Default for Goto {
@@ -47,7 +47,7 @@ impl fmt::Display for Goto {
 }
 
 /// Move cursor left.
-#[derive(Copy, Clone, PartialEq, Eq)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub struct Left(pub u16);
 
 impl fmt::Display for Left {
@@ -57,7 +57,7 @@ impl fmt::Display for Left {
 }
 
 /// Move cursor right.
-#[derive(Copy, Clone, PartialEq, Eq)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub struct Right(pub u16);
 
 impl fmt::Display for Right {
@@ -67,7 +67,7 @@ impl fmt::Display for Right {
 }
 
 /// Move cursor up.
-#[derive(Copy, Clone, PartialEq, Eq)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub struct Up(pub u16);
 
 impl fmt::Display for Up {
@@ -77,7 +77,7 @@ impl fmt::Display for Up {
 }
 
 /// Move cursor down.
-#[derive(Copy, Clone, PartialEq, Eq)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub struct Down(pub u16);
 
 impl fmt::Display for Down {

src/input.rs

@@ -7,6 +7,7 @@ use event::{self, Event, Key};
 use raw::IntoRawMode;
 
 /// An iterator over input keys.
+#[derive(Debug)]
 pub struct Keys<R> {
     iter: Events<R>,
 }
@@ -27,6 +28,7 @@ impl<R: Read> Iterator for Keys<R> {
 }
 
 /// An iterator over input events.
+#[derive(Debug)]
 pub struct Events<R>  {
     inner: EventsAndRaw<R>
 }
@@ -40,6 +42,7 @@ impl<R: Read> Iterator for Events<R> {
 }
 
 /// An iterator over input events and the bytes that define them.
+#[derive(Debug)]
 pub struct EventsAndRaw<R> {
     source: R,
     leftover: Option<u8>,
@@ -182,6 +185,7 @@ const EXIT_MOUSE_SEQUENCE: &'static str = csi!("?1006l\x1b[?1015l\x1b[?1002l\x1b
 /// A terminal with added mouse support.
 ///
 /// This can be obtained through the `From` implementations.
+#[derive(Debug)]
 pub struct MouseTerminal<W: Write> {
     term: W,
 }

src/lib.rs

@@ -9,6 +9,7 @@
 //! Supports Redox, Mac OS X, and Linux (or, in general, ANSI terminals).
 //!
 //! For more information refer to the [README](https://github.com/ticki/termion).
+#![deny(missing_debug_implementations)]
 #![warn(missing_docs)]
 
 #[cfg(target_os = "redox")]

src/macros.rs

@@ -7,7 +7,7 @@ macro_rules! csi {
 macro_rules! derive_csi_sequence {
     ($doc:expr, $name:ident, $value:expr) => {
         #[doc = $doc]
-        #[derive(Copy, Clone)]
+        #[derive(Copy, Clone, Debug)]
         pub struct $name;
 
         impl fmt::Display for $name {

src/raw.rs

@@ -22,27 +22,47 @@
 //! }
 //! ```
 
+use std::fmt;
 use std::io::{self, Write};
 use std::ops;
 
-use sys::Termios;
+use sys::Termios as SysTermios;
 use sys::attr::{get_terminal_attr, raw_terminal_attr, set_terminal_attr};
 
 /// The timeout of an escape code control sequence, in milliseconds.
 pub const CONTROL_SEQUENCE_TIMEOUT: u64 = 100;
 
+/// A wrapper around sys::Termios that implements std::fmt::Debug.
+struct Termios(SysTermios);
+
+impl fmt::Debug for Termios {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "termion::sys::Termios")
+    }
+}
+
+impl ops::Deref for Termios {
+    type Target = SysTermios;
+
+    fn deref(&self) -> &SysTermios {
+        &self.0
+    }
+
+}
+
 /// A terminal restorer, which keeps the previous state of the terminal, and restores it, when
 /// dropped.
 ///
 /// Restoring will entirely bring back the old TTY state.
+#[derive(Debug)]
 pub struct RawTerminal<W: Write> {
     prev_ios: Termios,
     output: W,
 }
 
 impl<W: Write> Drop for RawTerminal<W> {
     fn drop(&mut self) {
-        set_terminal_attr(&self.prev_ios).unwrap();
+        set_terminal_attr(&*self.prev_ios).unwrap();
     }
 }
 
@@ -95,7 +115,7 @@ impl<W: Write> IntoRawMode for W {
         set_terminal_attr(&ios)?;
 
         Ok(RawTerminal {
-            prev_ios: prev_ios,
+            prev_ios: Termios(prev_ios),
             output: self,
         })
     }

src/screen.rs

@@ -24,6 +24,7 @@ use std::ops;
 use std::fmt;
 
 /// Switch to the main screen buffer of the terminal.
+#[derive(Debug)]
 pub struct ToMainScreen;
 
 impl fmt::Display for ToMainScreen {
@@ -33,6 +34,7 @@ impl fmt::Display for ToMainScreen {
 }
 
 /// Switch to the alternate screen buffer of the terminal.
+#[derive(Debug)]
 pub struct ToAlternateScreen;
 
 impl fmt::Display for ToAlternateScreen {
@@ -46,6 +48,7 @@ impl fmt::Display for ToAlternateScreen {
 ///
 /// This is achieved by switching the terminal to the alternate screen on creation and
 /// automatically switching it back to the original screen on drop.
+#[derive(Debug)]
 pub struct AlternateScreen<W: Write> {
     /// The output target.
     output: W,

src/scroll.rs

@@ -3,7 +3,7 @@
 use std::fmt;
 
 /// Scroll up.
-#[derive(Copy, Clone, PartialEq, Eq)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub struct Up(pub u16);
 
 impl fmt::Display for Up {
@@ -13,7 +13,7 @@ impl fmt::Display for Up {
 }
 
 /// Scroll down.
-#[derive(Copy, Clone, PartialEq, Eq)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub struct Down(pub u16);
 
 impl fmt::Display for Down {