no need to forward all env vars

Author: RalfJung

src/tools/miri/miri-script/src/commands.rs

@@ -6,7 +6,7 @@ use std::ops::Not;
 use anyhow::{anyhow, bail, Context, Result};
 use path_macro::path;
 use walkdir::WalkDir;
-use xshell::cmd;
+use xshell::{cmd, Shell};
 
 use crate::util::*;
 use crate::Command;
@@ -91,7 +91,7 @@ impl Command {
         // Make sure rustup-toolchain-install-master is installed.
         which::which("rustup-toolchain-install-master")
             .context("Please install rustup-toolchain-install-master by running 'cargo install rustup-toolchain-install-master'")?;
-        let sh = shell()?;
+        let sh = Shell::new()?;
         sh.change_dir(miri_dir()?);
         let new_commit = Some(sh.read_file("rust-version")?.trim().to_owned());
         let current_commit = {
@@ -130,7 +130,7 @@ impl Command {
     }
 
     fn rustc_pull(commit: Option<String>) -> Result<()> {
-        let sh = shell()?;
+        let sh = Shell::new()?;
         sh.change_dir(miri_dir()?);
         let commit = commit.map(Result::Ok).unwrap_or_else(|| {
             let rust_repo_head =
@@ -177,7 +177,7 @@ impl Command {
     }
 
     fn rustc_push(github_user: String, branch: String) -> Result<()> {
-        let sh = shell()?;
+        let sh = Shell::new()?;
         sh.change_dir(miri_dir()?);
         let base = sh.read_file("rust-version")?.trim().to_owned();
         // Make sure the repo is clean.
@@ -265,7 +265,7 @@ impl Command {
         let Some((command_name, trailing_args)) = command.split_first() else {
             bail!("expected many-seeds command to be non-empty");
         };
-        let sh = shell()?;
+        let sh = Shell::new()?;
         for seed in seed_start..seed_end {
             println!("Trying seed: {seed}");
             let mut miriflags = env::var_os("MIRIFLAGS").unwrap_or_default();
@@ -293,7 +293,7 @@ impl Command {
         // Make sure we have an up-to-date Miri installed and selected the right toolchain.
         Self::install(vec![])?;
 
-        let sh = shell()?;
+        let sh = Shell::new()?;
         sh.change_dir(miri_dir()?);
         let benches_dir = "bench-cargo-miri";
         let benches = if benches.is_empty() {

src/tools/miri/miri-script/src/util.rs

@@ -13,21 +13,12 @@ pub fn miri_dir() -> std::io::Result<PathBuf> {
 
 /// Queries the active toolchain for the Miri dir.
 pub fn active_toolchain() -> Result<String> {
-    let sh = shell()?;
+    let sh = Shell::new()?;
     sh.change_dir(miri_dir()?);
     let stdout = cmd!(sh, "rustup show active-toolchain").read()?;
     Ok(stdout.split_whitespace().next().context("Could not obtain active Rust toolchain")?.into())
 }
 
-pub fn shell() -> Result<Shell> {
-    let sh = Shell::new()?;
-    // xshell does not propagate parent's env variables by default.
-    for (k, v) in std::env::vars_os() {
-        sh.set_var(k, v);
-    }
-    Ok(sh)
-}
-
 pub fn flagsplit(flags: &str) -> Vec<String> {
     // This code is taken from `RUSTFLAGS` handling in cargo.
     flags.split(' ').map(str::trim).filter(|s| !s.is_empty()).map(str::to_string).collect()
@@ -50,7 +41,7 @@ pub struct MiriEnv {
 impl MiriEnv {
     pub fn new() -> Result<Self> {
         let toolchain = active_toolchain()?;
-        let sh = shell()?; // we are preserving the current_dir on this one, so paths resolve properly!
+        let sh = Shell::new()?; // we are preserving the current_dir on this one, so paths resolve properly!
         let miri_dir = miri_dir()?;
 
         let sysroot = cmd!(sh, "rustc +{toolchain} --print sysroot").read()?.into();