clippy: deal with let bindings

In the auth code we rather #[allow] the binding, because in
this case we explicitly want to assert the type.

In fact, it would make more sense for clippy to not warn
about a unit type if the unit type is explicitly spelled
out.

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

src/api2/access/mod.rs

@@ -105,6 +105,7 @@ fn authenticate_user(
         }
     }
 
+    #[allow(clippy::let_unit_value)]
     let _: () = crate::auth::authenticate_user(userid, password)?;
 
     Ok(match crate::config::tfa::login_challenge(userid)? {
@@ -122,6 +123,7 @@ fn authenticate_2nd(
         .verify_with_time_frame(public_auth_key(), "PBS", Some(userid.as_str()), -60..600)?
         .require_partial()?;
 
+    #[allow(clippy::let_unit_value)]
     let _: () = crate::config::tfa::verify_challenge(userid, &challenge, response.parse()?)?;
 
     Ok(AuthResult::CreateTicket)

src/api2/access/tfa.rs

@@ -29,6 +29,7 @@ fn tfa_update_auth(
 
     if authid.user() != Userid::root_userid() {
         let password = password.ok_or_else(|| http_err!(UNAUTHORIZED, "missing password"))?;
+        #[allow(clippy::let_unit_value)]
         let _: () = crate::auth::authenticate_user(authid.user(), &password)
             .map_err(|err| http_err!(UNAUTHORIZED, "{}", err))?;
     }

src/api2/admin/datastore.rs

@@ -883,14 +883,13 @@ pub fn verify(
                 }
                 res
             } else if let Some(backup_group) = backup_group {
-                let failed_dirs = verify_backup_group(
+                verify_backup_group(
                     &verify_worker,
                     &backup_group,
                     &mut StoreProgress::new(1),
                     worker.upid(),
                     Some(&move |manifest| verify_filter(ignore_verified, outdated_after, manifest)),
-                )?;
-                failed_dirs
+                )?
             } else {
                 let owner = if owner_check_required {
                     Some(&auth_id)

src/api2/node/certificates.rs

@@ -373,7 +373,7 @@ async fn order_certificate(
             );
         }
 
-        let _: () = result?;
+        result?;
     }
 
     task_log!(worker, "All domains validated");

src/api2/pull.rs

@@ -280,12 +280,10 @@ async fn pull(
             );
 
             let pull_future = pull_store(&worker, &client, pull_params);
-            let future = select! {
+            (select! {
                 success = pull_future.fuse() => success,
                 abort = worker.abort_future().map(|_| Err(format_err!("pull aborted"))) => abort,
-            };
-
-            let _ = future?;
+            })?;
 
             task_log!(worker, "pull datastore '{}' end", store);