add strip-ansi-escape utility to wezterm package

I've been meaning to do this for a while: the intended purpose
is to use this to filter ansi escape sequences out of the prompt
in the shell pre-command hook.

Cargo.toml

@@ -4,6 +4,7 @@ name = "wezterm"
 version = "0.1.0"
 edition = "2018"
 build = "build.rs"
+default-run = "wezterm"
 
 [build-dependencies]
 vergen = "3"
@@ -11,6 +12,10 @@ vergen = "3"
 [target.'cfg(windows)'.build-dependencies]
 embed-resource = "1.3"
 
+[[bin]]
+name = "strip-ansi-escapes"
+path = "src/bin/strip-ansi-escapes.rs"
+
 [dependencies]
 allsorts = "0.1"
 async-task = "1.2"

ci/appimage.sh

@@ -4,6 +4,7 @@ rm -rf AppDir *.AppImage *.zsync
 mkdir AppDir
 
 install -Dsm755 -t AppDir/usr/bin target/release/wezterm
+install -Dsm755 -t AppDir/usr/bin target/release/strip-ansi-escapes
 install -Dm644 assets/icon/terminal.png AppDir/usr/share/icons/hicolor/128x128/apps/org.wezfurlong.wezterm.png
 install -Dm644 -t AppDir/usr/share/wezterm/colors assets/colors/*
 install -Dm644 assets/wezterm.desktop AppDir/usr/share/applications/org.wezfurlong.wezterm.desktop

ci/deploy.sh

@@ -27,6 +27,7 @@ case $OSTYPE in
     mkdir $zipdir
     cp -r assets/macos/WezTerm.app $zipdir/
     cp $TARGET_DIR/release/wezterm $zipdir/WezTerm.app
+    cp $TARGET_DIR/release/strip-ansi-escapes $zipdir/WezTerm.app
     cp -r assets/colors $zipdir/WezTerm.app/Contents/Resources/
     zip -r $zipname $zipdir
     ;;
@@ -40,6 +41,7 @@ case $OSTYPE in
     rm -rf $zipdir $zipname
     mkdir $zipdir
     cp $TARGET_DIR/release/wezterm.exe \
+      $TARGET_DIR/release/strip-ansi-escapes.exe \
       $TARGET_DIR/release/wezterm.pdb \
       assets/windows/conhost/conpty.dll \
       assets/windows/conhost/OpenConsole.exe \
@@ -76,6 +78,7 @@ set -x
 cd ${HERE}
 mkdir -p %{buildroot}/usr/bin %{buildroot}/usr/share/wezterm/colors %{buildroot}/usr/share/applications
 install -Dsm755 target/release/wezterm %{buildroot}/usr/bin
+install -Dsm755 target/release/strip-ansi-escapes %{buildroot}/usr/bin
 install -Dm644 assets/icon/terminal.png %{buildroot}/usr/share/icons/hicolor/128x128/apps/org.wezfurlong.wezterm.png
 install -Dm644 -t %{buildroot}/usr/share/wezterm/colors assets/colors/*
 install -Dm644 assets/wezterm.desktop %{buildroot}/usr/share/applications/org.wezfurlong.wezterm.desktop
@@ -83,6 +86,7 @@ install -Dm644 assets/wezterm.appdata.xml %{buildroot}/usr/share/metainfo/org.we
 
 %files
 /usr/bin/wezterm
+/usr/bin/strip-ansi-escapes
 /usr/share/icons/hicolor/128x128/apps/org.wezfurlong.wezterm.png
 /usr/share/wezterm/colors/*
 /usr/share/applications/org.wezfurlong.wezterm.desktop
@@ -110,6 +114,7 @@ Description: Wez's Terminal Emulator.
 Depends: libc6, libegl-mesa0, libxcb-icccm4, libxcb-ewmh2, libxcb-keysyms1, libxcb-xkb1, libxkbcommon0, libxkbcommon-x11-0, libfontconfig1, xdg-utils, libxcb-render0, libxcb-shape0, libx11-6, libegl1
 EOF
         install -Dsm755 -t pkg/debian/usr/bin target/release/wezterm
+        install -Dsm755 -t pkg/debian/usr/bin target/release/strip-ansi-escapes
         install -Dm644 assets/icon/terminal.png pkg/debian/usr/share/icons/hicolor/128x128/apps/org.wezfurlong.wezterm.png
         install -Dm644 -t pkg/debian/usr/share/wezterm/colors assets/colors/*
         install -Dm644 assets/wezterm.desktop pkg/debian/usr/share/applications/org.wezfurlong.wezterm.desktop

src/bin/strip-ansi-escapes.rs

@@ -0,0 +1,42 @@
+use std::io::{Read, Result};
+use structopt::StructOpt;
+use termwiz::escape::parser::Parser;
+use termwiz::escape::{Action, ControlCode};
+
+#[derive(Debug, StructOpt)]
+#[structopt(
+    global_setting = structopt::clap::AppSettings::ColoredHelp,
+)]
+/// This is a little utility that strips escape sequences from
+/// stdin and prints the result on stdout.
+/// It preserves only printable characters and CL, LF and HT.
+///
+/// This utility is part of WezTerm.
+///
+/// https://github.com/wez/wezterm
+struct Opt {}
+
+fn main() -> Result<()> {
+    let _ = Opt::from_args();
+    let mut buf = [0u8; 4096];
+
+    let mut parser = Parser::new();
+
+    loop {
+        let len = std::io::stdin().read(&mut buf)?;
+        if len == 0 {
+            return Ok(());
+        }
+
+        parser.parse(&buf[0..len], |action| match action {
+            Action::Print(c) => print!("{}", c),
+            Action::Control(c) => match c {
+                ControlCode::HorizontalTab
+                | ControlCode::LineFeed
+                | ControlCode::CarriageReturn => print!("{}", c as u8 as char),
+                _ => {}
+            },
+            _ => {}
+        });
+    }
+}