Make clippy happy

- Applied many of the `clippy` suggestions.

src/crypto.rs

@@ -46,10 +46,7 @@ pub fn get_local_trust_root(cert_store: &CertStore) -> anyhow::Result<Cert> {
                 Ok(mut parser) => {
                     match parser.next() {
                         Some(Ok(cert)) => {
-                            match Cert::from_bytes(cert.as_bytes()) {
-                                Ok(c) => Some(c),
-                                Err(_) => None,
-                            }
+                            Cert::from_bytes(cert.as_bytes()).ok()
                         },
                         Some(Err(_))
                         | None => None
@@ -89,7 +86,7 @@ pub fn get_local_certificates<'hc>(context: &HuskContext<'hc>, email: &str)
     for (fpr, some_userid) in bindings {
         if let Some(userid) = some_userid {
             let paths = n.authenticate(userid, &fpr, wot::FULLY_TRUSTED);
-            if paths.len() > 0 {
+            if !paths.is_empty() {
                 log::debug!("{} authenticated!!!", email);
                 for (path, _) in paths.iter() {
                     if let Ok(cert) = cert_store.lookup_by_cert_fpr(&path.target().fingerprint()) {
@@ -125,34 +122,32 @@ pub async fn lookup_certificates<'hc>(context: &HuskContext<'hc>, email: &str)
     let collect_certs = |certs: Vec<Result<Cert, anyhow::Error>>, email: String, policy: &StandardPolicy| {
         let mut result = Vec::new();
 
-        for cert in certs {
-            if let Ok(c) = cert {
-                if let Ok(vc) = c.with_policy(policy, None) {
+        for cert in certs.into_iter().flatten() {
+            if let Ok(vc) = cert.with_policy(policy, None) {
 
-                    // check if the returned certificate contains a userid with the
-                    // email address in question.
-                    let mut userid_found = false;
-                    for userid in vc.userids() {
-                        if let Ok(Some(u)) = userid.userid().email() {
-                            if u == email {
-                                userid_found = true;
-                            }
+                // check if the returned certificate contains a userid with the
+                // email address in question.
+                let mut userid_found = false;
+                for userid in vc.userids() {
+                    if let Ok(Some(u)) = userid.userid().email() {
+                        if u == email {
+                            userid_found = true;
                         }
                     }
+                }
 
-                    if userid_found {
-                        // check if the certificate can be used (for encryption).
-                        vc.keys()
-                            .supported()
-                            .alive()
-                            .revoked(false)
-                            .for_transport_encryption()
-                            .for_each(|_| {
-                                // XXX: cert gets returned for each transport key
-                                // once would be enough
-                                result.push(c.clone());
-                            });
-                    }
+                if userid_found {
+                    // check if the certificate can be used (for encryption).
+                    vc.keys()
+                        .supported()
+                        .alive()
+                        .revoked(false)
+                        .for_transport_encryption()
+                        .for_each(|_| {
+                            // XXX: cert gets returned for each transport key
+                            // once would be enough
+                            result.push(cert.clone());
+                        });
                 }
             }
         }
@@ -239,7 +234,7 @@ pub async fn get_certificates<'hc>(context: &HuskContext<'hc>, email: &str)
     log::debug!("get certificate for {}", email);
 
     let locals = get_local_certificates(context, email);
-    if locals.len() > 0 {
+    if !locals.is_empty() {
         return locals;
     }
 
@@ -363,7 +358,7 @@ pub fn encrypt(context: &HuskContext<'_>, body: &Bytes, recipients: &Vec<Recipie
             }
         }
     }
-    if keys.len() > 0 {
+    if !keys.is_empty() {
         let mut sink = Vec::new();
         let message = Message::new(&mut sink);
         let message = Armorer::new(message).build()?;

src/daemon/mod.rs

@@ -94,7 +94,7 @@ impl Daemon {
         match HuskContext::new(&config) {
             Ok(context) => {
                 log::debug!("found introducers: {:?}", context.introducers);
-                cx.data = Some(context).take();
+                cx.data = Some(context);
                 Status::Continue
             },
             Err(e) => {
@@ -138,13 +138,12 @@ impl Daemon {
                     break;
                 }
             }
-            if rcpt.is_none() {
-                Status::Tempfail
-            } else {
-                context.add_recipient(rcpt.unwrap()).await;
+            if let Some(rcpt) = rcpt {
+                context.add_recipient(rcpt).await;
                 Status::Continue
+            } else {
+                Status::Tempfail
             }
-
         } else {
             Status::Tempfail
         }
@@ -213,7 +212,7 @@ impl Daemon {
 
             if protection == ProtectionPossibility::Full {
                 // if an error occures the body is not exchanged
-                match crypto::encrypt(&context, &body, &context.mail.recipients) {
+                match crypto::encrypt(context, &body, &context.mail.recipients) {
                     Ok(encrypted) => {
                         if cx.actions.replace_body(&encrypted).await.is_err() {
                             log::error!("Cannot exchange body");

src/types/husk_context.rs

@@ -59,7 +59,7 @@ impl<'hc> HuskContext<'hc> {
 
     pub async fn add_recipient(&mut self, rcpt: String) {
 
-        let certs = crypto::get_certificates(&self, rcpt.as_str()).await;
+        let certs = crypto::get_certificates(self, rcpt.as_str()).await;
 
         self.mail.add_recipient(rcpt, certs)
     }

src/types/introducer.rs

@@ -64,7 +64,7 @@ impl Display for Introducer {
             .map(|u| String::from_utf8_lossy(u.userid().value()).to_string())
             .collect::<Vec<String>>()
             .join(", ");
-        write!(f, "Introducer: {}\n", self.cert.fingerprint())?;
+        writeln!(f, "Introducer: {}", self.cert.fingerprint())?;
         write!(f, "  UserIDs: {}", uids)?;
         Ok(())
     }

src/types/mail_context.rs

@@ -66,6 +66,13 @@ impl<'mc> MailContext<'mc> {
 
 }
 
+/// Default Mailcontext
+impl<'mc> Default for MailContext<'mc> {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl From<&MailContext<'_>> for ProtectionPossibility {
     fn from(mail_context: &MailContext<'_>) -> ProtectionPossibility {
         let mut can_encrypt = false;

src/types/recipient.rs

@@ -17,8 +17,8 @@ pub struct Recipient<'r> {
 
 impl From<String> for Recipient<'_> {
     fn from(email: String) -> Self {
-        Recipient { 
-            email: email, 
+        Recipient {
+            email,
             certs: Vec::new()
         }
     }
@@ -40,7 +40,7 @@ impl Recipient<'_> {
     /// check if this Recipient can encrypt.
     // XXX: currently this check is naive
     pub fn can_encrypt(&self) -> bool {
-        if self.certs.len() == 0 { 
+        if self.certs.is_empty() {
             return false;
         }