1 files changed, 165 insertions, 0 deletions

diff --git a/xtask/src/not_bash.rs b/xtask/src/not_bash.rs
new file mode 100644
index 000000000..3e30e7279
--- /dev/null
+++ b/xtask/src/not_bash.rs
@@ -0,0 +1,165 @@
+//! A bad shell -- small cross platform module for writing glue code
+use std::{
+    cell::RefCell,
+    env,
+    ffi::OsStr,
+    fs,
+    path::{Path, PathBuf},
+    process::{Command, Stdio},
+};
+
+use anyhow::{bail, Context, Result};
+
+pub mod fs2 {
+    use std::{fs, path::Path};
+
+    use anyhow::{Context, Result};
+
+    pub fn read_dir<P: AsRef<Path>>(path: P) -> Result<fs::ReadDir> {
+        let path = path.as_ref();
+        fs::read_dir(path).with_context(|| format!("Failed to read {}", path.display()))
+    }
+
+    pub fn write<P: AsRef<Path>, C: AsRef<[u8]>>(path: P, contents: C) -> Result<()> {
+        let path = path.as_ref();
+        fs::write(path, contents).with_context(|| format!("Failed to write {}", path.display()))
+    }
+
+    pub fn copy<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> Result<u64> {
+        let from = from.as_ref();
+        let to = to.as_ref();
+        fs::copy(from, to)
+            .with_context(|| format!("Failed to copy {} to {}", from.display(), to.display()))
+    }
+
+    pub fn remove_file<P: AsRef<Path>>(path: P) -> Result<()> {
+        let path = path.as_ref();
+        fs::remove_file(path).with_context(|| format!("Failed to remove file {}", path.display()))
+    }
+
+    pub fn remove_dir_all<P: AsRef<Path>>(path: P) -> Result<()> {
+        let path = path.as_ref();
+        fs::remove_dir_all(path).with_context(|| format!("Failed to remove dir {}", path.display()))
+    }
+}
+
+macro_rules! _run {
+    ($($expr:expr),*) => {
+        run!($($expr),*; echo = true)
+    };
+    ($($expr:expr),* ; echo = $echo:expr) => {
+        $crate::not_bash::run_process(format!($($expr),*), $echo)
+    };
+}
+pub(crate) use _run as run;
+
+pub struct Pushd {
+    _p: (),
+}
+
+pub fn pushd(path: impl Into<PathBuf>) -> Pushd {
+    Env::with(|env| env.pushd(path.into()));
+    Pushd { _p: () }
+}
+
+impl Drop for Pushd {
+    fn drop(&mut self) {
+        Env::with(|env| env.popd())
+    }
+}
+
+pub fn rm(glob: &str) -> Result<()> {
+    let cwd = Env::with(|env| env.cwd());
+    ls(glob)?.into_iter().try_for_each(|it| fs::remove_file(cwd.join(it)))?;
+    Ok(())
+}
+
+pub fn rm_rf(path: impl AsRef<Path>) -> Result<()> {
+    let path = path.as_ref();
+    if path.is_file() {
+        fs2::remove_file(path)
+    } else {
+        fs2::remove_dir_all(path)
+    }
+}
+
+pub fn ls(glob: &str) -> Result<Vec<PathBuf>> {
+    let cwd = Env::with(|env| env.cwd());
+    let mut res = Vec::new();
+    for entry in fs::read_dir(&cwd)? {
+        let entry = entry?;
+        if matches(&entry.file_name(), glob) {
+            let path = entry.path();
+            let path = path.strip_prefix(&cwd).unwrap();
+            res.push(path.to_path_buf())
+        }
+    }
+    return Ok(res);
+
+    fn matches(file_name: &OsStr, glob: &str) -> bool {
+        assert!(glob.starts_with('*'));
+        file_name.to_string_lossy().ends_with(&glob[1..])
+    }
+}
+
+#[doc(hidden)]
+pub fn run_process(cmd: String, echo: bool) -> Result<String> {
+    run_process_inner(&cmd, echo).with_context(|| format!("process `{}` failed", cmd))
+}
+
+fn run_process_inner(cmd: &str, echo: bool) -> Result<String> {
+    let cwd = Env::with(|env| env.cwd());
+    let mut args = shelx(cmd);
+    let binary = args.remove(0);
+
+    if echo {
+        println!("> {}", cmd)
+    }
+
+    let output = Command::new(binary)
+        .args(args)
+        .current_dir(cwd)
+        .stdin(Stdio::null())
+        .stderr(Stdio::inherit())
+        .output()?;
+    let stdout = String::from_utf8(output.stdout)?;
+
+    if echo {
+        print!("{}", stdout)
+    }
+
+    if !output.status.success() {
+        bail!("{}", output.status)
+    }
+
+    Ok(stdout.trim().to_string())
+}
+
+// FIXME: some real shell lexing here
+fn shelx(cmd: &str) -> Vec<String> {
+    cmd.split_whitespace().map(|it| it.to_string()).collect()
+}
+
+#[derive(Default)]
+struct Env {
+    pushd_stack: Vec<PathBuf>,
+}
+
+impl Env {
+    fn with<F: FnOnce(&mut Env) -> T, T>(f: F) -> T {
+        thread_local! {
+            static ENV: RefCell<Env> = Default::default();
+        }
+        ENV.with(|it| f(&mut *it.borrow_mut()))
+    }
+
+    fn pushd(&mut self, dir: PathBuf) {
+        self.pushd_stack.push(dir)
+    }
+    fn popd(&mut self) {
+        self.pushd_stack.pop().unwrap();
+    }
+    fn cwd(&self) -> PathBuf {
+        self.pushd_stack.last().cloned().unwrap_or_else(|| env::current_dir().unwrap())
+    }
+}