dist: clarify when update_hash is available

Author: djc

src/dist/manifestation.rs

@@ -361,7 +361,7 @@ impl Manifestation {
     pub(crate) async fn update_v1(
         &self,
         new_manifest: &[String],
-        update_hash: Option<&Path>,
+        update_hash: &Path,
         dl_cfg: &DownloadCfg<'_>,
     ) -> Result<Option<String>> {
         // If there's already a v2 installation then something has gone wrong
@@ -387,7 +387,7 @@ impl Manifestation {
 
         let status = dl_cfg.status_for("rust");
         let dl = dl_cfg
-            .download_and_check(&url, update_hash, Some(&status), ".tar.gz")
+            .download_and_check(&url, Some(update_hash), Some(&status), ".tar.gz")
             .await?;
         if dl.is_none() {
             return Ok(None);

src/dist/mod.rs

@@ -880,7 +880,7 @@ pub(crate) struct DistOptions<'a> {
     pub(crate) cfg: &'a Cfg<'a>,
     pub(crate) toolchain: &'a ToolchainDesc,
     pub(crate) profile: Profile,
-    pub(crate) update_hash: Option<&'a Path>,
+    pub(crate) update_hash: &'a Path,
     pub(crate) dl_cfg: DownloadCfg<'a>,
     /// --force bool is whether to force an update/install
     pub(crate) force: bool,
@@ -907,15 +907,13 @@ pub(crate) async fn update_from_dist(
     opts: &DistOptions<'_>,
 ) -> Result<Option<String>> {
     let fresh_install = !prefix.path().exists();
-    if let Some(hash) = opts.update_hash {
-        // fresh_install means the toolchain isn't present, but hash_exists means there is a stray hash file
-        if fresh_install && Path::exists(hash) {
-            warn!(
-                "removing stray hash file in order to continue: {}",
-                hash.display()
-            );
-            std::fs::remove_file(hash)?;
-        }
+    // fresh_install means the toolchain isn't present, but hash_exists means there is a stray hash file
+    if fresh_install && Path::exists(opts.update_hash) {
+        warn!(
+            "removing stray hash file in order to continue: {}",
+            opts.update_hash.display()
+        );
+        std::fs::remove_file(opts.update_hash)?;
     }
 
     let mut fetched = String::new();
@@ -1068,7 +1066,7 @@ pub(crate) async fn update_from_dist(
 #[allow(clippy::too_many_arguments)]
 async fn try_update_from_dist_(
     download: &DownloadCfg<'_>,
-    update_hash: Option<&Path>,
+    update_hash: &Path,
     toolchain: &ToolchainDesc,
     profile: Option<Profile>,
     prefix: &InstallPrefix,
@@ -1090,7 +1088,7 @@ async fn try_update_from_dist_(
         // So if components or targets is not empty, we skip passing `update_hash` so that
         // we essentially degenerate to `rustup component add` / `rustup target add`
         if components.is_empty() && targets.is_empty() {
-            update_hash
+            Some(update_hash)
         } else {
             None
         },

src/install.rs

@@ -107,10 +107,7 @@ impl InstallMethod<'_> {
                 let maybe_new_hash = dist::update_from_dist(prefix, opts).await?;
 
                 if let Some(hash) = maybe_new_hash {
-                    if let Some(hash_file) = opts.update_hash {
-                        utils::write_file("update hash", hash_file, &hash)?;
-                    }
-
+                    utils::write_file("update hash", opts.update_hash, &hash)?;
                     Ok(true)
                 } else {
                     Ok(false)

src/toolchain/distributable.rs

@@ -1,6 +1,6 @@
 #[cfg(windows)]
 use std::fs;
-use std::{convert::Infallible, env::consts::EXE_SUFFIX, ffi::OsStr, path::Path, process::Command};
+use std::{convert::Infallible, env::consts::EXE_SUFFIX, ffi::OsStr, process::Command};
 
 #[cfg(windows)]
 use anyhow::Context;
@@ -346,13 +346,11 @@ impl<'a> DistributableToolchain<'a> {
         force: bool,
     ) -> anyhow::Result<(UpdateStatus, DistributableToolchain<'a>)> {
         let hash_path = cfg.get_hash_file(toolchain, true)?;
-        let update_hash = Some(&hash_path as &Path);
-
         let status = InstallMethod::Dist(DistOptions {
             cfg,
             toolchain,
             profile,
-            update_hash,
+            update_hash: &hash_path,
             dl_cfg: DownloadCfg::new(cfg),
             force,
             allow_downgrade: false,
@@ -404,13 +402,11 @@ impl<'a> DistributableToolchain<'a> {
 
         let cfg = self.toolchain.cfg;
         let hash_path = cfg.get_hash_file(&self.desc, true)?;
-        let update_hash = Some(&hash_path as &Path);
-
         InstallMethod::Dist(DistOptions {
             cfg,
             toolchain: &self.desc,
             profile,
-            update_hash,
+            update_hash: &hash_path,
             dl_cfg: DownloadCfg::new(cfg),
             force,
             allow_downgrade,