openpgp: Apply clippy::manual_map.

  - Improve clarity by replacing

    match Some(0) {
      Some(x) => Some(x + 1),
      None => None,
    };

    with Some(0).map(|x| x + 1);

3 files changed, 12 insertions, 16 deletions

diff --git a/openpgp/src/packet/literal.rs b/openpgp/src/packet/literal.rs
index 14b98b38..f534f51c 100644
--- a/openpgp/src/packet/literal.rs
+++ b/openpgp/src/packet/literal.rs
@@ -51,11 +51,10 @@ assert_send_and_sync!(Literal);
 
 impl fmt::Debug for Literal {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        let filename = if let Some(ref filename) = self.filename {
-            Some(String::from_utf8_lossy(filename))
-        } else {
-            None
-        };
+        let filename = self
+            .filename
+            .as_ref()
+            .map(|filename| String::from_utf8_lossy(filename));
 
         let threshold = 36;
         let body = self.body();
diff --git a/openpgp/src/packet/signature.rs b/openpgp/src/packet/signature.rs
index 464e30cd..bc48b733 100644
--- a/openpgp/src/packet/signature.rs
+++ b/openpgp/src/packet/signature.rs
@@ -1750,12 +1750,13 @@ impl fmt::Debug for Signature4 {
             .field("additional_issuers", &self.additional_issuers)
             .field("digest_prefix",
                    &crate::fmt::to_hex(&self.digest_prefix, false))
-            .field("computed_digest",
-                   &if let Some(ref hash) = self.computed_digest {
-                       Some(crate::fmt::to_hex(&hash[..], false))
-                   } else {
-                       None
-                   })
+            .field(
+                "computed_digest",
+                &self
+                    .computed_digest
+                    .as_ref()
+                    .map(|hash| crate::fmt::to_hex(&hash[..], false)),
+            )
             .field("level", &self.level)
             .field("mpis", &self.mpis)
             .finish()
diff --git a/openpgp/src/parse/partial_body.rs b/openpgp/src/parse/partial_body.rs
index e0904869..0ae9bad4 100644
--- a/openpgp/src/parse/partial_body.rs
+++ b/openpgp/src/parse/partial_body.rs
@@ -59,11 +59,7 @@ impl<T: BufferedReader<Cookie>> std::fmt::Debug
             .field("last", &self.last)
             .field("hash headers", &self.hash_headers)
             .field("buffer (bytes left)",
-                   &if let Some(ref buffer) = self.buffer {
-                       Some(buffer.len())
-                   } else {
-                       None
-                   })
+                   &self.buffer.as_ref().map(|buffer| buffer.len()))
             .field("reader", &self.reader)
             .finish()
     }