compiler/rustc_feature/src/tests.rs

   1 use super::UnstableFeatures;
   2
   3 #[test]
   4 fn rustc_bootstrap_parsing() {
   5     let is_bootstrap = |env, krate| {
   6         std::env::set_var("RUSTC_BOOTSTRAP", env);
   7         matches!(UnstableFeatures::from_environment(krate), UnstableFeatures::Cheat)
   8     };
   9     assert!(is_bootstrap("1", None));
  10     assert!(is_bootstrap("1", Some("x")));
  11     // RUSTC_BOOTSTRAP allows specifying a specific crate
  12     assert!(is_bootstrap("x", Some("x")));
  13     // RUSTC_BOOTSTRAP allows multiple comma-delimited crates
  14     assert!(is_bootstrap("x,y,z", Some("x")));
  15     assert!(is_bootstrap("x,y,z", Some("y")));
  16     // Crate that aren't specified do not get unstable features
  17     assert!(!is_bootstrap("x", Some("a")));
  18     assert!(!is_bootstrap("x,y,z", Some("a")));
  19     assert!(!is_bootstrap("x,y,z", None));
  20
  21     // this is technically a breaking change, but there are no stability guarantees for RUSTC_BOOTSTRAP
  22     assert!(!is_bootstrap("0", None));
  23 }