Thread toolchain through to error message

In the component-unavailable error case, we need to report the
full toolchain rather than just the component and target name.
This threads it through and reports it in the error message.

Fixes: #1596

Signed-off-by: Daniel Silverstone <dsilvers@digital-scurf.org>

Author: kinnison

src/rustup-dist/src/dist.rs

@@ -556,6 +556,7 @@ pub fn update_from_dist_<'a>(
                 force_update,
                 &download,
                 download.notify_handler.clone(),
+                &toolchain.manifest_name(),
             )? {
                 UpdateStatus::Unchanged => Ok(None),
                 UpdateStatus::Changed => Ok(Some(hash)),

src/rustup-dist/src/errors.rs

@@ -107,9 +107,9 @@ error_chain! {
             description("missing package for the target of a rename")
             display("server sent a broken manifest: missing package for the target of a rename {}", name)
         }
-        RequestedComponentsUnavailable(c: Vec<Component>, manifest: Manifest) {
+        RequestedComponentsUnavailable(c: Vec<Component>, manifest: Manifest, toolchain: String) {
             description("some requested components are unavailable to download")
-            display("{}", component_unavailable_msg(&c, &manifest))
+            display("{} for channel '{}'", component_unavailable_msg(&c, &manifest), toolchain)
         }
     }
 }

src/rustup-dist/src/manifestation.rs

@@ -111,6 +111,7 @@ impl Manifestation {
         force_update: bool,
         download_cfg: &DownloadCfg<'_>,
         notify_handler: &dyn Fn(Notification<'_>),
+        toolchain_str: &str,
     ) -> Result<UpdateStatus> {
         // Some vars we're going to need a few times
         let temp_cfg = download_cfg.temp_cfg;
@@ -126,10 +127,10 @@ impl Manifestation {
         }
 
         // Make sure we don't accidentally uninstall the essential components! (see #1297)
-        update.missing_essential_components(&self.target_triple, new_manifest)?;
+        update.missing_essential_components(&self.target_triple, new_manifest, toolchain_str)?;
 
         // Validate that the requested components are available
-        match update.unavailable_components(new_manifest) {
+        match update.unavailable_components(new_manifest, toolchain_str) {
             Ok(_) => {}
             _ if force_update => {}
             Err(e) => return Err(e),
@@ -594,6 +595,7 @@ impl Update {
         &self,
         target_triple: &TargetTriple,
         manifest: &Manifest,
+        toolchain_str: &str,
     ) -> Result<()> {
         let missing_essential_components = ["rustc", "cargo"]
             .iter()
@@ -614,14 +616,15 @@ impl Update {
             return Err(ErrorKind::RequestedComponentsUnavailable(
                 missing_essential_components,
                 manifest.clone(),
+                toolchain_str.to_owned(),
             )
             .into());
         }
 
         Ok(())
     }
 
-    fn unavailable_components(&self, new_manifest: &Manifest) -> Result<()> {
+    fn unavailable_components(&self, new_manifest: &Manifest, toolchain_str: &str) -> Result<()> {
         let mut unavailable_components: Vec<Component> = self
             .components_to_install
             .iter()
@@ -642,6 +645,7 @@ impl Update {
             return Err(ErrorKind::RequestedComponentsUnavailable(
                 unavailable_components,
                 new_manifest.clone(),
+                toolchain_str.to_owned(),
             )
             .into());
         }

src/rustup-dist/tests/dist.rs

@@ -422,6 +422,7 @@ fn update_from_dist_(
         force_update,
         download_cfg,
         download_cfg.notify_handler.clone(),
+        &toolchain.to_string(),
     )
 }
 

src/rustup/toolchain.rs

@@ -594,6 +594,7 @@ impl<'a> Toolchain<'a> {
                 false,
                 &self.download_cfg(),
                 self.download_cfg().notify_handler.clone(),
+                &toolchain.manifest_name(),
             )?;
 
             Ok(())
@@ -663,6 +664,7 @@ impl<'a> Toolchain<'a> {
                 false,
                 &self.download_cfg(),
                 self.download_cfg().notify_handler.clone(),
+                &toolchain.manifest_name(),
             )?;
 
             Ok(())

tests/cli-v2.rs

@@ -836,8 +836,8 @@ fn update_unavailable_std() {
             config,
             &["rustup", "update", "nightly", "--no-self-update"],
             &format!(
-                "component 'rust-std' for target '{}' is unavailable for download",
-                trip
+                "component 'rust-std' for target '{}' is unavailable for download for channel 'nightly'",
+                trip,
             ),
         );
     });
@@ -864,8 +864,8 @@ fn update_unavailable_force() {
             config,
             &["rustup", "update", "nightly", "--no-self-update"],
             &format!(
-                "component 'rls' for target '{}' is unavailable for download",
-                trip
+                "component 'rls' for target '{}' is unavailable for download for channel 'nightly'",
+                trip,
             ),
         );
         expect_ok(