Favor error from alias resolution over trailing args

Author: weihanglo

src/bin/cargo/cli.rs

@@ -231,26 +231,25 @@ fn expand_aliases(
 ) -> Result<(ArgMatches, GlobalArgs), CliError> {
     if let Some((cmd, args)) = args.subcommand() {
         let exec = commands::builtin_exec(cmd);
-        let aliased_cmd = super::aliased_command(config, cmd).or_else(|e| {
-            // HACK: `cargo version` must always work even with malformed configs.
-            // Here we treat the error as the aliased command not found,
-            // so it falls back to call builtin `cargo version`
-            if cmd == "version" {
-                Ok(None)
-            } else {
-                Err(e)
-            }
-        })?;
+        let aliased_cmd = super::aliased_command(config, cmd);
 
         match (exec, aliased_cmd) {
-            (Some(_), Some(_)) => {
+            (_, Err(e)) => {
+                // HACK: `cargo version` must always work even with malformed configs.
+                // so when cmd is exactly `version`, it ignores the error
+                // and falls back to call builtin `cargo version` then.
+                if cmd != "version" {
+                    return Err(e.into());
+                }
+            }
+            (Some(_), Ok(Some(_))) => {
                 // User alias conflicts with a built-in subcommand
                 config.shell().warn(format!(
                     "user-defined alias `{}` is ignored, because it is shadowed by a built-in command",
                     cmd,
                 ))?;
             }
-            (Some(_), None) => {
+            (Some(_), Ok(None)) => {
                 // Command is built-in and is not conflicting with alias, but contains ignored values.
                 if let Some(mut values) = args.get_many::<String>("") {
                     return Err(anyhow::format_err!(
@@ -264,8 +263,8 @@ To pass the arguments to the subcommand, remove `--`",
                     .into());
                 }
             }
-            (None, None) => {}
-            (_, Some(mut alias)) => {
+            (None, Ok(None)) => {}
+            (None, Ok(Some(mut alias))) => {
                 // Check if this alias is shadowing an external subcommand
                 // (binary of the form `cargo-<subcommand>`)
                 // Currently this is only a warning, but after a transition period this will become