Merge #1193

1193: suggest reinstalling the toolchain r=Emilgardis a=Emilgardis

also fixes suggestion when using wrong channel

resolves #1192 

Co-authored-by: Emil Gardström <[email protected]>

Author: bors[bot]

src/lib.rs

@@ -553,10 +553,7 @@ pub fn run(
                     .with_suggestion(|| {
                         format!(
                             "try `cross +{}` instead",
-                            Toolchain {
-                                host: None,
-                                ..picked_toolchain
-                            }
+                            picked_toolchain.remove_host()
                         )
                     }).with_section(|| format!(
 r#"Overriding the toolchain in cross is only possible in CLI by specifying a channel and optional date: `+channel[-YYYY-MM-DD]`.
@@ -574,7 +571,8 @@ To override the toolchain mounted in the image, set `target.{}.image.toolchain =
         let image = image.to_definite_with(&engine, msg_info);
 
         toolchain.replace_host(&image.platform);
-        let maybe_warn = matches!(toolchain.channel.as_str(), "stable" | "beta" | "nightly");
+        let picked_generic_channel =
+            matches!(toolchain.channel.as_str(), "stable" | "beta" | "nightly");
 
         if image.platform.target.is_supported(Some(&target)) {
             if image.platform.architecture != toolchain.host().architecture {
@@ -593,7 +591,9 @@ To override the toolchain mounted in the image, set `target.{}.image.toolchain =
                 rustup::install_toolchain(&toolchain, msg_info)?;
             }
             let available_targets = if !toolchain.is_custom {
-                rustup::available_targets(&toolchain.full, msg_info)?
+                rustup::available_targets(&toolchain.full, msg_info).with_note(|| {
+                    format!("cross would use the toolchain '{toolchain}' for mounting rust")
+                })?
             } else {
                 rustup::AvailableTargets {
                     default: String::new(),
@@ -604,7 +604,7 @@ To override the toolchain mounted in the image, set `target.{}.image.toolchain =
 
             let mut rustc_version = None;
             if let Some((version, channel, commit)) = toolchain.rustc_version()? {
-                if maybe_warn && toolchain.date.is_none() {
+                if picked_generic_channel && toolchain.date.is_none() {
                     warn_host_version_mismatch(
                         &host_version_meta,
                         &toolchain,

src/rustc.rs

@@ -284,6 +284,19 @@ pub struct Toolchain {
     pub full: String,
 }
 
+impl Toolchain {
+    pub fn remove_host(&self) -> Self {
+        let mut new = Self {
+            host: None,
+            ..self.clone()
+        };
+        if let Some(host) = &self.host {
+            new.full = new.full.replace(&format!("-{host}"), "");
+        }
+        new
+    }
+}
+
 impl std::fmt::Display for Toolchain {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         f.write_str(&self.full)

src/rustup.rs

@@ -1,8 +1,6 @@
 use std::path::PathBuf;
 use std::process::Command;
 
-use color_eyre::owo_colors::OwoColorize;
-use color_eyre::SectionExt;
 use rustc_version::{Channel, Version};
 
 use crate::errors::*;
@@ -93,14 +91,22 @@ pub fn available_targets(
         .suggestion("is rustup installed?")?;
 
     if !output.status.success() {
-        if String::from_utf8_lossy(&output.stderr).contains("is a custom toolchain") {
-            return Err(eyre::eyre!("`{toolchain}` is a custom toolchain.").with_section(|| r#"To use this toolchain with cross, you'll need to set the environment variable `CROSS_CUSTOM_TOOLCHAIN=1`
-cross will not attempt to configure the toolchain further so that it can run your binary."#.header("Suggestion".bright_cyan())));
-        }
-        return Err(cmd
+        let mut err = cmd
             .status_result(msg_info, output.status, Some(&output))
             .expect_err("we know the command failed")
-            .to_section_report());
+            .to_section_report();
+        if String::from_utf8_lossy(&output.stderr).contains("is a custom toolchain") {
+            err = err.wrap_err("'{toolchain}' is a custom toolchain.")
+            .suggestion(r#"To use this toolchain with cross, you'll need to set the environment variable `CROSS_CUSTOM_TOOLCHAIN=1`
+cross will not attempt to configure the toolchain further so that it can run your binary."#);
+        } else if String::from_utf8_lossy(&output.stderr).contains("does not support components") {
+            err = err.suggestion(format!(
+                "try reinstalling the '{toolchain}' toolchain
+$ rustup toolchain uninstall {toolchain}
+$ rustup toolchain install {toolchain} --force-non-host"
+            ));
+        }
+        return Err(err);
     }
     let out = output.stdout()?;
     let mut default = String::new();