feat(rustup-mode): install the active toolchain by default on rustup toolchain install

src/cli/rustup_mode.rs

@@ -100,14 +100,14 @@ fn plus_toolchain_value_parser(s: &str) -> clap::error::Result<ResolvableToolcha
 #[derive(Debug, Subcommand)]
 #[command(name = "rustup", bin_name = "rustup[EXE]")]
 enum RustupSubcmd {
-    /// Update Rust toolchains
+    /// Install or update the given toolchains, or by default the active toolchain
     #[command(hide = true, after_help = INSTALL_HELP)]
     Install {
         #[command(flatten)]
         opts: UpdateOpts,
     },
 
-    /// Uninstall Rust toolchains
+    /// Uninstall the given toolchains
     #[command(hide = true)]
     Uninstall {
         #[command(flatten)]
@@ -302,14 +302,14 @@ enum ToolchainSubcmd {
         quiet: bool,
     },
 
-    /// Install or update a given toolchain
+    /// Install or update the given toolchains, or by default the active toolchain
     #[command(aliases = ["update", "add"] )]
     Install {
         #[command(flatten)]
         opts: UpdateOpts,
     },
 
-    /// Uninstall a toolchain
+    /// Uninstall the given toolchains
     #[command(alias = "remove")]
     Uninstall {
         #[command(flatten)]
@@ -330,7 +330,6 @@ enum ToolchainSubcmd {
 #[derive(Debug, Default, Args)]
 struct UpdateOpts {
     #[arg(
-        required = true,
         help = OFFICIAL_TOOLCHAIN_ARG_HELP,
         num_args = 1..,
     )]
@@ -584,7 +583,7 @@ pub async fn main(current_dir: PathBuf, process: &Process) -> Result<utils::Exit
 
     match subcmd {
         RustupSubcmd::DumpTestament => common::dump_testament(process),
-        RustupSubcmd::Install { opts } => update(cfg, opts).await,
+        RustupSubcmd::Install { opts } => update(cfg, opts, true).await,
         RustupSubcmd::Uninstall { opts } => toolchain_remove(cfg, opts),
         RustupSubcmd::Show { verbose, subcmd } => handle_epipe(match subcmd {
             None => show(cfg, verbose),
@@ -610,11 +609,12 @@ pub async fn main(current_dir: PathBuf, process: &Process) -> Result<utils::Exit
                     force_non_host,
                     ..UpdateOpts::default()
                 },
+                false,
             )
             .await
         }
         RustupSubcmd::Toolchain { subcmd } => match subcmd {
-            ToolchainSubcmd::Install { opts } => update(cfg, opts).await,
+            ToolchainSubcmd::Install { opts } => update(cfg, opts, true).await,
             ToolchainSubcmd::List { verbose, quiet } => {
                 handle_epipe(common::list_toolchains(cfg, verbose, quiet))
             }
@@ -791,7 +791,11 @@ async fn check_updates(cfg: &Cfg<'_>) -> Result<utils::ExitCode> {
     Ok(utils::ExitCode(0))
 }
 
-async fn update(cfg: &mut Cfg<'_>, opts: UpdateOpts) -> Result<utils::ExitCode> {
+async fn update(
+    cfg: &mut Cfg<'_>,
+    opts: UpdateOpts,
+    ensure_active_toolchain: bool,
+) -> Result<utils::ExitCode> {
     let mut exit_code = utils::ExitCode(0);
 
     common::warn_if_host_is_emulated(cfg.process);
@@ -861,6 +865,13 @@ async fn update(cfg: &mut Cfg<'_>, opts: UpdateOpts) -> Result<utils::ExitCode>
         if self_update {
             exit_code &= common::self_update(|| Ok(()), cfg.process).await?;
         }
+    } else if ensure_active_toolchain {
+        let (toolchain, reason) = cfg.find_or_install_active_toolchain(true).await?;
+        info!(
+            "the active toolchain `{}` has been installed",
+            toolchain.name()
+        );
+        info!("it's active because: {reason}");
     } else {
         exit_code &= common::update_all_channels(cfg, self_update, opts.force).await?;
         info!("cleaning up downloads & tmp directories");

src/config.rs

@@ -510,7 +510,7 @@ impl<'a> Cfg<'a> {
                     LocalToolchainName::Named(ToolchainName::Official(desc)),
                 )?)
             }
-            None => Ok(self.find_or_install_active_toolchain().await?.0),
+            None => Ok(self.find_or_install_active_toolchain(false).await?.0),
         }
     }
 
@@ -718,7 +718,7 @@ impl<'a> Cfg<'a> {
                 let desc = name.resolve(&self.get_default_host_triple()?)?;
                 Toolchain::new(self, desc.into())?
             }
-            None => self.find_or_install_active_toolchain().await?.0,
+            None => self.find_or_install_active_toolchain(false).await?.0,
         })
     }
 
@@ -732,12 +732,15 @@ impl<'a> Cfg<'a> {
 
         Ok(match local {
             Some(tc) => Toolchain::from_local(tc, false, self).await?,
-            None => self.find_or_install_active_toolchain().await?.0,
+            None => self.find_or_install_active_toolchain(false).await?.0,
         })
     }
 
     #[tracing::instrument(level = "trace", skip_all)]
-    async fn find_or_install_active_toolchain(&'a self) -> Result<(Toolchain<'a>, ActiveReason)> {
+    pub(crate) async fn find_or_install_active_toolchain(
+        &'a self,
+        verbose: bool,
+    ) -> Result<(Toolchain<'a>, ActiveReason)> {
         match self.find_override_config()? {
             Some((override_config, reason)) => match override_config {
                 OverrideCfg::PathBased(path_based_name) => {
@@ -755,7 +758,7 @@ impl<'a> Cfg<'a> {
                     profile,
                 } => {
                     let toolchain = self
-                        .ensure_installed(&toolchain, components, targets, profile, false)
+                        .ensure_installed(&toolchain, components, targets, profile, verbose)
                         .await?
                         .1;
                     Ok((toolchain, reason))
@@ -771,7 +774,7 @@ impl<'a> Cfg<'a> {
                 Some(ToolchainName::Official(toolchain_desc)) => {
                     let reason = ActiveReason::Default;
                     let toolchain = self
-                        .ensure_installed(&toolchain_desc, vec![], vec![], None, false)
+                        .ensure_installed(&toolchain_desc, vec![], vec![], None, verbose)
                         .await?
                         .1;
                     Ok((toolchain, reason))

tests/suite/cli-ui/rustup/rustup_toolchain_cmd_help_flag_stdout.toml

@@ -8,8 +8,8 @@ Usage: rustup[EXE] toolchain <COMMAND>
 
 Commands:
   list       List installed toolchains
-  install    Install or update a given toolchain
-  uninstall  Uninstall a toolchain
+  install    Install or update the given toolchains, or by default the active toolchain
+  uninstall  Uninstall the given toolchains
   link       Create a custom toolchain by symlinking to a directory
   help       Print this message or the help of the given subcommand(s)
 

tests/suite/cli-ui/rustup/rustup_toolchain_cmd_install_cmd_help_flag_stdout.toml

@@ -1,13 +1,12 @@
 bin.name = "rustup"
 args = ["toolchain", "install", "--help"]
 stdout = """
-...
-Install or update a given toolchain
+Install or update the given toolchains, or by default the active toolchain
 
-Usage: rustup[EXE] toolchain install [OPTIONS] <TOOLCHAIN>...
+Usage: rustup[EXE] toolchain install [OPTIONS] [TOOLCHAIN]...
 
 Arguments:
-  <TOOLCHAIN>...  Toolchain name, such as 'stable', 'nightly', or '1.8.0'. For more information see
+  [TOOLCHAIN]...  Toolchain name, such as 'stable', 'nightly', or '1.8.0'. For more information see
                   `rustup help toolchain`
 
 Options:

tests/suite/cli-ui/rustup/rustup_toolchain_cmd_uninstall_cmd_help_flag_stdout.toml

@@ -1,8 +1,7 @@
 bin.name = "rustup"
 args = ["toolchain", "uninstall", "--help"]
 stdout = """
-...
-Uninstall a toolchain
+Uninstall the given toolchains
 
 Usage: rustup[EXE] toolchain uninstall <TOOLCHAIN>...
 

tests/suite/cli_rustup.rs

@@ -1450,12 +1450,49 @@ async fn toolchain_install_is_like_update_quiet() {
 }
 
 #[tokio::test]
-async fn toolchain_install_is_like_update_except_that_bare_install_is_an_error() {
-    let cx = CliTestContext::new(Scenario::None).await;
+async fn toolchain_install_without_args_installs_active() {
+    let cx = CliTestContext::new(Scenario::SimpleV2).await;
+
+    let cwd = cx.config.current_dir();
+    let toolchain_file = cwd.join("rust-toolchain.toml");
+    raw::write_file(
+        &toolchain_file,
+        r#"
+[toolchain]
+profile = "minimal"
+channel = "nightly"
+"#,
+    )
+    .unwrap();
+
     cx.config
-        .expect_err(
+        .expect_stderr_ok(
             &["rustup", "toolchain", "install"],
-            "arguments were not provided",
+            &format!(
+                "\
+info: syncing channel updates for 'nightly-{0}'
+info: latest update on 2015-01-02, rust version 1.3.0 (hash-nightly-2)
+info: downloading component 'rustc'
+info: installing component 'rustc'
+info: the active toolchain `nightly-{0}` has been installed
+info: it's active because: overridden by '{1}'",
+                this_host_triple(),
+                toolchain_file.display(),
+            ),
+        )
+        .await;
+
+    cx.config
+        .expect_stderr_ok(
+            &["rustup", "toolchain", "install"],
+            &format!(
+                "\
+info: using existing install for 'nightly-{0}'
+info: the active toolchain `nightly-{0}` has been installed
+info: it's active because: overridden by '{1}'",
+                this_host_triple(),
+                toolchain_file.display(),
+            ),
         )
         .await;
 }
@@ -1494,17 +1531,6 @@ async fn toolchain_uninstall_is_like_uninstall() {
         .await;
 }
 
-#[tokio::test]
-async fn toolchain_update_is_like_update_except_that_bare_install_is_an_error() {
-    let cx = CliTestContext::new(Scenario::None).await;
-    cx.config
-        .expect_err(
-            &["rustup", "toolchain", "update"],
-            "arguments were not provided",
-        )
-        .await;
-}
-
 #[tokio::test]
 async fn proxy_toolchain_shorthand() {
     let mut cx = CliTestContext::new(Scenario::SimpleV2).await;