Workaround rustup env issue when setting toolchain #702

CHANGELOG.md

@@ -1,5 +1,9 @@
 ## CHANGELOG
 
+### v0.36.0
+
+* Enhancement: Workaround rustup env issue when setting toolchain #702
+
 ### v0.35.16 (2022-08-08)
 
 * Enhancement: Create task definition in runtime and invoke it via plugin #677

examples/toolchain.toml

@@ -21,17 +21,27 @@ dependencies = [
   "rustc-version-nightly",
 ]
 
-[tasks.echo-cargo-stable]
-toolchain = "stable"
+[tasks.echo-cargo-env]
 script = '''
-echo ${CARGO}
+echo CARGO=${CARGO}
+echo RUSTC=${RUSTC}
+echo RUSTDOC=${RUSTDOC}
+echo RUSTFLAGS=${RUSTFLAGS}
 '''
 
+[tasks.echo-cargo-stable]
+extend = "echo-cargo-env"
+toolchain = "stable"
+
+[tasks.stable]
+alias = "echo-cargo-stable"
+
 [tasks.echo-cargo-nightly]
+extend = "echo-cargo-env"
 toolchain = "nightly"
-script = '''
-echo ${CARGO}
-'''
+
+[tasks.nightly]
+alias = "echo-cargo-nightly"
 
 [tasks.echo-cargo-all]
 dependencies = ["echo-cargo-stable", "echo-cargo-nightly"]

src/lib/cli.rs

@@ -18,6 +18,7 @@ use crate::profile;
 use crate::recursion_level;
 use crate::runner;
 use crate::time_summary;
+use crate::toolchain;
 use crate::types::{CliArgs, GlobalConfig};
 use crate::version;
 use std::time::SystemTime;
@@ -52,6 +53,9 @@ fn run(cli_args: CliArgs, global_config: &GlobalConfig) {
         version::check();
     }
 
+    // clear env vars (see https://github.com/rust-lang/rustup/issues/3029)
+    toolchain::remove_rust_env_vars();
+
     let cwd_string_option = match cli_args.cwd.clone() {
         Some(value) => Some(value),
         None => match global_config.search_project_root {

src/lib/toolchain.rs

@@ -7,9 +7,9 @@
 #[path = "toolchain_test.rs"]
 mod toolchain_test;
 
-use semver::{Prerelease, Version};
-
 use crate::types::{CommandSpec, ToolchainSpecifier};
+use envmnt;
+use semver::{Prerelease, Version};
 use std::process::{Command, Stdio};
 
 pub(crate) fn wrap_command(
@@ -128,3 +128,7 @@ pub(crate) fn get_cargo_binary_path(toolchain: &ToolchainSpecifier) -> Option<St
         Some(binary_path.to_string())
     }
 }
+
+pub(crate) fn remove_rust_env_vars() {
+    envmnt::remove_all(&vec!["RUSTC", "RUSTDOC", "RUSTFLAGS"]);
+}

src/lib/toolchain_test.rs

@@ -86,3 +86,20 @@ fn get_cargo_binary_path_valid() {
     assert!(binary_path_value.find("bin").is_some());
     assert!(binary_path_value.find("cargo").is_some());
 }
+
+#[test]
+fn remove_rust_env_vars_existed() {
+    envmnt::set("RUSTC", "bad1");
+    envmnt::set("RUSTDOC", "bad2");
+    envmnt::set("RUSTFLAGS", "bad3");
+
+    assert!(envmnt::exits("RUSTC"));
+    assert!(envmnt::exits("RUSTDOC"));
+    assert!(envmnt::exits("RUSTFLAGS"));
+
+    remove_rust_env_vars();
+
+    assert!(!envmnt::exits("RUSTC"));
+    assert!(!envmnt::exits("RUSTDOC"));
+    assert!(!envmnt::exits("RUSTFLAGS"));
+}