Improve CI debugability

The call count assertion is binary; the failure explanation could be
varied

download/tests/read-proxy-env.rs

@@ -72,8 +72,12 @@ async fn socks_proxy_request() {
 
     if let Err(e) = res {
         let s = e.source().unwrap();
+        assert!(
+            s.to_string().contains("socks connect error"),
+            "Expected socks connect error, got: {}",
+            s.to_string()
+        );
         assert_eq!(CALL_COUNT.load(Ordering::SeqCst), 1);
-        assert!(s.to_string().contains("socks connect error"));
     } else {
         panic!("Socks proxy was ignored")
     }

src/bin/rustup-init.rs

@@ -117,7 +117,7 @@ async fn run_rustup_inner() -> Result<utils::ExitCode> {
             // name. Browsers rename duplicates to
             // e.g. rustup-setup(2), and this allows all variations
             // to work.
-            setup_mode::main()
+            setup_mode::main().await
         }
         Some(n) if n.starts_with("rustup-gc-") => {
             // This is the final uninstallation stage on windows where

src/cli/setup_mode.rs

@@ -14,7 +14,7 @@ use crate::{
 };
 
 #[cfg_attr(feature = "otel", tracing::instrument)]
-pub fn main() -> Result<utils::ExitCode> {
+pub async fn main() -> Result<utils::ExitCode> {
     let args: Vec<_> = process().args().collect();
     let arg1 = args.get(1).map(|a| &**a);
 
@@ -157,5 +157,5 @@ pub fn main() -> Result<utils::ExitCode> {
         warn!("{}", common::WARN_COMPLETE_PROFILE);
     }
 
-    utils::run_future(self_update::install(no_prompt, verbose, quiet, opts))
+    self_update::install(no_prompt, verbose, quiet, opts).await
 }