Order can be important if cargo tests are run inside the rustc build system

Author: oli-obk

src/cargo/core/features.rs

@@ -354,14 +354,14 @@ impl CliUnstable {
 }
 
 fn channel() -> String {
+    if let Ok(override_channel) = env::var("__CARGO_TEST_CHANNEL_OVERRIDE_DO_NOT_USE_THIS") {
+        return override_channel;
+    }
     if let Ok(staging) = env::var("RUSTC_BOOTSTRAP") {
         if staging == "1" {
             return "dev".to_string();
         }
     }
-    if let Ok(override_channel) = env::var("__CARGO_TEST_CHANNEL_OVERRIDE_DO_NOT_USE_THIS") {
-        return override_channel;
-    }
     ::version()
         .cfg_info
         .map(|c| c.release_channel)