update code as per comments

Author: bentongxyz

.devcontainer/Dockerfile

@@ -437,12 +437,11 @@ impl<'a> ShouldRun<'a> {
 
     // single alias, which does not correspond to any on-disk path
     pub fn alias(mut self, alias: &str) -> Self {
-        // exceptional case for `Kind::Setup` because its `library` 
+        // exceptional case for `Kind::Setup` because its `library`
         // and `compiler` options would otherwise naively match with
         // `compiler` and `library` folders respectively.
         assert!(
-            self.kind == Kind::Setup 
-            || !self.builder.src.join(alias).exists(),
+            self.kind == Kind::Setup || !self.builder.src.join(alias).exists(),
             "use `builder.path()` for real paths: {}",
             alias
         );

.devcontainer/devcontainer.json

@@ -10,6 +10,7 @@ use getopts::Options;
 use crate::builder::{Builder, Kind};
 use crate::config::{Config, TargetSelection};
 use crate::setup::Profile;
+use crate::util::t;
 use crate::{Build, DocTests};
 
 #[derive(Copy, Clone)]
@@ -543,7 +544,7 @@ Arguments:
             Kind::Bench | Kind::Clean | Kind::Dist | Kind::Install => {}
         };
         // Get any optional paths which occur after the subcommand
-        let paths = matches.free[1..].iter().map(|p| p.into()).collect::<Vec<PathBuf>>();
+        let mut paths = matches.free[1..].iter().map(|p| p.into()).collect::<Vec<PathBuf>>();
 
         let verbose = matches.opt_present("verbose");
 
@@ -614,7 +615,26 @@ Arguments:
                 }
                 Subcommand::Run { paths }
             }
-            Kind::Setup => Subcommand::Setup { paths },
+            Kind::Setup => {
+                let profile = if paths.len() > 1 {
+                    println!("\nat most one profile can be passed to setup\n");
+                    usage(1, &opts, verbose, &subcommand_help)
+                } else if let Some(path) = paths.pop() {
+                    let profile_string = t!(path.into_os_string().into_string().map_err(
+                        |path| format!("{} is not a valid UTF8 string", path.to_string_lossy())
+                    ));
+
+                    profile_string.parse().unwrap_or_else(|err| {
+                        eprintln!("error: {}", err);
+                        eprintln!("help: the available profiles are:");
+                        eprint!("{}", Profile::all_for_help("- "));
+                        crate::detail_exit(1);
+                    })
+                } else {
+                    t!(crate::setup::interactive_path())
+                };
+                Subcommand::Setup { paths: vec![PathBuf::from(profile.as_str())] }
+            }
         };
 
         Flags {