Merge #833

833: Fix error message with cross-util with invalid command. r=Emilgardis a=Alexhuszagh

Changes the error message to properly report the invalid command, when an invalid command is provided.

Co-authored-by: Alex Huszagh <[email protected]>

Author: bors[bot]

src/bin/cross-util.rs

@@ -1,6 +1,6 @@
 #![deny(missing_debug_implementations, rust_2018_idioms)]
 
-use clap::{Parser, Subcommand};
+use clap::{CommandFactory, Parser, Subcommand};
 
 mod commands;
 
@@ -14,6 +14,13 @@ struct Cli {
     command: Commands,
 }
 
+// hidden implied parser so we can get matches without recursion.
+#[derive(Parser, Debug)]
+struct CliHidden {
+    #[clap(subcommand)]
+    command: Commands,
+}
+
 #[derive(Subcommand, Debug)]
 enum Commands {
     /// List cross images in local storage.
@@ -25,7 +32,8 @@ fn is_toolchain(toolchain: &str) -> cross::Result<String> {
     if toolchain.starts_with('+') {
         Ok(toolchain.chars().skip(1).collect())
     } else {
-        eyre::bail!("not a toolchain")
+        let _ = <CliHidden as CommandFactory>::command().get_matches();
+        unreachable!();
     }
 }
 

xtask/src/main.rs

@@ -10,7 +10,7 @@ pub mod util;
 use std::path::PathBuf;
 
 use ci::CiJob;
-use clap::{Parser, Subcommand};
+use clap::{CommandFactory, Parser, Subcommand};
 use util::ImageTarget;
 
 use self::build_docker_image::BuildDockerImage;
@@ -28,6 +28,13 @@ struct Cli {
     command: Commands,
 }
 
+// hidden implied parser so we can get matches without recursion.
+#[derive(Parser, Debug)]
+struct CliHidden {
+    #[clap(subcommand)]
+    command: Commands,
+}
+
 #[derive(Subcommand, Debug)]
 enum Commands {
     /// Extract and print info for targets.
@@ -49,7 +56,8 @@ fn is_toolchain(toolchain: &str) -> cross::Result<String> {
     if toolchain.starts_with('+') {
         Ok(toolchain.chars().skip(1).collect())
     } else {
-        eyre::bail!("not a toolchain")
+        let _ = <CliHidden as CommandFactory>::command().get_matches();
+        unreachable!();
     }
 }