ci: update to Rust 1.76 and fix clippy warnings

.github/workflows/ci.yml

@@ -24,7 +24,7 @@ jobs:
     name: Lint Rust
     runs-on: ubuntu-latest
     env:
-      RUSTUP_TOOLCHAIN: 1.75.0
+      RUSTUP_TOOLCHAIN: 1.76.0
     steps:
       - uses: actions/checkout@v4
         with:
@@ -83,11 +83,11 @@ jobs:
       matrix:
         include:
           - os: ubuntu-latest
-            rust: 1.75.0
+            rust: 1.76.0
           - os: windows-latest
-            rust: 1.75.0
+            rust: 1.76.0
           - os: macos-latest
-            rust: 1.75.0
+            rust: 1.76.0
 
           # Minimum Supported Rust Version = 1.70.0
           - os: ubuntu-latest

src/key.rs

@@ -79,7 +79,7 @@ pub(crate) trait DcKey: Serialize + Deserializable + KeyTrait + Clone {
 }
 
 pub(crate) async fn load_self_public_key(context: &Context) -> Result<SignedPublicKey> {
-    match context
+    let public_key = context
         .sql
         .query_row_optional(
             "SELECT public_key
@@ -91,8 +91,8 @@ pub(crate) async fn load_self_public_key(context: &Context) -> Result<SignedPubl
                 Ok(bytes)
             },
         )
-        .await?
-    {
+        .await?;
+    match public_key {
         Some(bytes) => SignedPublicKey::from_slice(&bytes),
         None => {
             let keypair = generate_keypair(context).await?;
@@ -102,7 +102,7 @@ pub(crate) async fn load_self_public_key(context: &Context) -> Result<SignedPubl
 }
 
 pub(crate) async fn load_self_secret_key(context: &Context) -> Result<SignedSecretKey> {
-    match context
+    let private_key = context
         .sql
         .query_row_optional(
             "SELECT private_key
@@ -114,8 +114,8 @@ pub(crate) async fn load_self_secret_key(context: &Context) -> Result<SignedSecr
                 Ok(bytes)
             },
         )
-        .await?
-    {
+        .await?;
+    match private_key {
         Some(bytes) => SignedSecretKey::from_slice(&bytes),
         None => {
             let keypair = generate_keypair(context).await?;

src/smtp.rs

@@ -804,7 +804,7 @@ async fn send_mdn(context: &Context, smtp: &mut Smtp) -> Result<bool> {
         .sql
         .execute("DELETE FROM smtp_mdns WHERE retries > 6", [])
         .await?;
-    let msg_row = match context
+    let Some(msg_row) = context
         .sql
         .query_row_optional(
             "SELECT msg_id, from_id FROM smtp_mdns ORDER BY retries LIMIT 1",
@@ -816,9 +816,8 @@ async fn send_mdn(context: &Context, smtp: &mut Smtp) -> Result<bool> {
             },
         )
         .await?
-    {
-        Some(msg_row) => msg_row,
-        None => return Ok(false),
+    else {
+        return Ok(false);
     };
     let (msg_id, contact_id) = msg_row;