Join nested if statements with logical and into one statement

Instead of this:

    if foo {
        if bar {
           ...
        }
    }

do this:

    if foo && bar {
        ...
    }

Nesting statements implies a more complicated code structure than it
really is. Thus it's arguably simpler to write a combined condition by
joining the two conditions with a logical and operation.

Found by clippy lint collapsible_if:
https://rust-lang.github.io/rust-clippy/master/index.html#collapsible_if

11 files changed, 66 insertions, 104 deletions

diff --git a/ipc/src/core.rs b/ipc/src/core.rs
index b4dd928a..6712921b 100644
--- a/ipc/src/core.rs
+++ b/ipc/src/core.rs
@@ -179,12 +179,10 @@ impl Config {
             let tmp = tempfile::Builder::new().prefix("sequoia").tempdir()?;
             c.home = tmp.into_path();
             c.cleanup = true;
-        } else {
-            if home_not_set {
-                c.home = dirs::home_dir()
-                    .ok_or_else(|| anyhow::anyhow!("Failed to get users home directory"))?
-                    .join(".sequoia");
-            }
+        } else if home_not_set {
+            c.home = dirs::home_dir()
+                .ok_or_else(|| anyhow::anyhow!("Failed to get users home directory"))?
+            .join(".sequoia");
         }
         Ok(c)
     }
diff --git a/openpgp/src/cert/amalgamation/key/iter.rs b/openpgp/src/cert/amalgamation/key/iter.rs
index 370a4e43..d2ec0fe6 100644
--- a/openpgp/src/cert/amalgamation/key/iter.rs
+++ b/openpgp/src/cert/amalgamation/key/iter.rs
@@ -175,11 +175,9 @@ impl<'a, P, R> KeyAmalgamationIter<'a, P, R>
                         t!("PK algo is supported... skipping.");
                         continue;
                     }
-                } else {
-                    if want_supported {
-                        t!("PK algo is not supported... skipping.");
-                        continue;
-                    }
+                } else if want_supported {
+                    t!("PK algo is not supported... skipping.");
+                    continue;
                 }
             }
 
@@ -190,11 +188,9 @@ impl<'a, P, R> KeyAmalgamationIter<'a, P, R>
                         t!("Have a secret... skipping.");
                         continue;
                     }
-                } else {
-                    if want_secret {
-                        t!("No secret... skipping.");
-                        continue;
-                    }
+                } else if want_secret {
+                    t!("No secret... skipping.");
+                    continue;
                 }
             }
 
@@ -205,11 +201,9 @@ impl<'a, P, R> KeyAmalgamationIter<'a, P, R>
                             t!("Unencrypted secret... skipping.");
                             continue;
                         }
-                    } else {
-                        if want_unencrypted_secret {
-                            t!("Encrypted secret... skipping.");
-                            continue;
-                        }
+                    } else if want_unencrypted_secret {
+                        t!("Encrypted secret... skipping.");
+                        continue;
                     }
                 } else {
                     // No secret.
@@ -797,11 +791,9 @@ impl<'a, P, R> ValidKeyAmalgamationIter<'a, P, R>
                         t!("PK algo is supported... skipping.");
                         continue;
                     }
-                } else {
-                    if want_supported {
-                        t!("PK algo is not supported... skipping.");
-                        continue;
-                    }
+                } else if want_supported {
+                    t!("PK algo is not supported... skipping.");
+                    continue;
                 }
             }
 
@@ -843,11 +835,9 @@ impl<'a, P, R> ValidKeyAmalgamationIter<'a, P, R>
                         t!("Have a secret... skipping.");
                         continue;
                     }
-                } else {
-                    if want_secret {
-                        t!("No secret... skipping.");
-                        continue;
-                    }
+                } else if want_secret {
+                    t!("No secret... skipping.");
+                    continue;
                 }
             }
 
@@ -858,11 +848,9 @@ impl<'a, P, R> ValidKeyAmalgamationIter<'a, P, R>
                             t!("Unencrypted secret... skipping.");
                             continue;
                         }
-                    } else {
-                        if want_unencrypted_secret {
-                            t!("Encrypted secret... skipping.");
-                            continue;
-                        }
+                    } else if want_unencrypted_secret {
+                        t!("Encrypted secret... skipping.");
+                        continue;
                     }
                 } else {
                     // No secret.
diff --git a/openpgp/src/cert/builder.rs b/openpgp/src/cert/builder.rs
index 0ceb0579..235f2cd9 100644
--- a/openpgp/src/cert/builder.rs
+++ b/openpgp/src/cert/builder.rs
@@ -1336,17 +1336,15 @@ impl CertBuilder<'_> {
                     a.remove_all(SubpacketTag::PrimaryUserID);
                     Ok(a)
                 })?;
+            } else if have_primary_user_thing {
+                // Check if this is the first explicitly selected
+                // user thing.
+                emitted_primary_user_thing |=
+                    sig.primary_userid().unwrap_or(false);
             } else {
-                if have_primary_user_thing {
-                    // Check if this is the first explicitly selected
-                    // user thing.
-                    emitted_primary_user_thing |=
-                        sig.primary_userid().unwrap_or(false);
-                } else {
-                    // Implicitly mark the first as primary.
-                    sig = sig.set_primary_userid(true)?;
-                    emitted_primary_user_thing = true;
-                }
+                // Implicitly mark the first as primary.
+                sig = sig.set_primary_userid(true)?;
+                emitted_primary_user_thing = true;
             }
 
             let signature = uid.bind(&mut signer, &cert, sig)?;
@@ -1368,17 +1366,15 @@ impl CertBuilder<'_> {
                     a.remove_all(SubpacketTag::PrimaryUserID);
                     Ok(a)
                 })?;
+            } else if have_primary_user_thing {
+                // Check if this is the first explicitly selected
+                // user thing.
+                emitted_primary_user_thing |=
+                    sig.primary_userid().unwrap_or(false);
             } else {
-                if have_primary_user_thing {
-                    // Check if this is the first explicitly selected
-                    // user thing.
-                    emitted_primary_user_thing |=
-                        sig.primary_userid().unwrap_or(false);
-                } else {
-                    // Implicitly mark the first as primary.
-                    sig = sig.set_primary_userid(true)?;
-                    emitted_primary_user_thing = true;
-                }
+                // Implicitly mark the first as primary.
+                sig = sig.set_primary_userid(true)?;
+                emitted_primary_user_thing = true;
             }
 
             let signature = ua.bind(&mut signer, &cert, sig)?;
diff --git a/openpgp/src/cert/parser/mod.rs b/openpgp/src/cert/parser/mod.rs
index 02516428..15afbdd9 100644
--- a/openpgp/src/cert/parser/mod.rs
+++ b/openpgp/src/cert/parser/mod.rs
@@ -904,12 +904,10 @@ pub(crate) fn split_sigs<C>(primary: &KeyHandle, primary_keyid: &KeyHandle,
             } else {
                 other_revs.push(sig);
             }
+        } else if is_selfsig {
+            self_signatures.push(sig);
         } else {
-            if is_selfsig {
-                self_signatures.push(sig);
-            } else {
-                certifications.push(sig);
-            }
+            certifications.push(sig);
         }
     }
 
diff --git a/openpgp/src/packet/signature.rs b/openpgp/src/packet/signature.rs
index 2db99a39..359ea7a5 100644
--- a/openpgp/src/packet/signature.rs
+++ b/openpgp/src/packet/signature.rs
@@ -2316,10 +2316,8 @@ impl crate::packet::Signature {
             };
 
             let l = p.serialized_len();
-            if size + l <= std::u16::MAX as usize {
-                if acc.insert(p.clone()) {
-                    size += l;
-                }
+            if size + l <= std::u16::MAX as usize && acc.insert(p.clone()) {
+                size += l;
             }
         }
 
@@ -2343,10 +2341,8 @@ impl crate::packet::Signature {
                    .filter(|p| eligible(p) && ! p.authenticated() && ! prefer(p)))
         {
             let l = p.serialized_len();
-            if size + l <= std::u16::MAX as usize {
-                if acc.insert(p.clone()) {
-                    size += l;
-                }
+            if size + l <= std::u16::MAX as usize && acc.insert(p.clone()) {
+                size += l;
             }
         }
         assert!(size <= std::u16::MAX as usize);
diff --git a/openpgp/src/parse.rs b/openpgp/src/parse.rs
index 8a323b89..5cf7c5f5 100644
--- a/openpgp/src/parse.rs
+++ b/openpgp/src/parse.rs
@@ -2229,12 +2229,10 @@ impl Key4<key::UnspecifiedParts, key::UnspecifiedRole>
                     format!("Unexpected secret key found in {:?} packet", tag)
                 ).into());
             }
-        } else {
-            if tag == Tag::SecretKey || tag == Tag::SecretSubkey {
-                return php.error(Error::MalformedPacket(
-                    format!("Expected secret key in {:?} packet", tag)
-                ).into());
-            }
+        } else if tag == Tag::SecretKey || tag == Tag::SecretSubkey {
+            return php.error(Error::MalformedPacket(
+                format!("Expected secret key in {:?} packet", tag)
+            ).into());
         }
 
         fn k<R>(creation_time: u32,
diff --git a/openpgp/src/parse/stream.rs b/openpgp/src/parse/stream.rs
index efb5755e..8d92dab5 100644
--- a/openpgp/src/parse/stream.rs
+++ b/openpgp/src/parse/stream.rs
@@ -2325,11 +2325,9 @@ impl<'a, H: VerificationHelper + DecryptionHelper> Decryptor<'a, H> {
                         format!("Expected signature, got {}", pp.packet.tag()))
                                .into());
                 }
-            } else {
-                if let Err(err) = pp.possible_message() {
-                    t!("Malformed message: {}", err);
-                    return Err(err.context("Malformed OpenPGP message"));
-                }
+            } else if let Err(err) = pp.possible_message() {
+                t!("Malformed message: {}", err);
+                return Err(err.context("Malformed OpenPGP message"));
             }
 
             let sym_algo_hint = if let Packet::AED(ref aed) = pp.packet {
diff --git a/openpgp/src/regex/mod.rs b/openpgp/src/regex/mod.rs
index a7e911de..0584bcbe 100644
--- a/openpgp/src/regex/mod.rs
+++ b/openpgp/src/regex/mod.rs
@@ -453,10 +453,8 @@ impl Regex {
     ///
     ///   [`char::is_control`]: https://doc.rust-lang.org/std/primitive.char.html#method.is_control
     pub fn is_match(&self, s: &str) -> bool {
-        if ! self.disable_sanitizations {
-            if s.chars().any(char::is_control) {
-                return false;
-            }
+        if ! self.disable_sanitizations && s.chars().any(char::is_control) {
+            return false;
         }
 
         self.is_match_clean(s)
@@ -975,10 +973,8 @@ impl RegexSet {
     /// # Ok(()) }
     /// ```
     pub fn is_match(&self, s: &str) -> bool {
-        if ! self.disable_sanitizations {
-            if s.chars().any(char::is_control) {
-                return false;
-            }
+        if ! self.disable_sanitizations && s.chars().any(char::is_control) {
+            return false;
         }
 
         match self.re_set {
diff --git a/openpgp/src/serialize/stream.rs b/openpgp/src/serialize/stream.rs
index 53068489..cbfa1117 100644
--- a/openpgp/src/serialize/stream.rs
+++ b/openpgp/src/serialize/stream.rs
@@ -1409,12 +1409,10 @@ impl<'a> Write for Signer<'a> {
                 // later, we will hash it then.  Otherwise, it is
                 // implicitly omitted when the signer is finalized.
                 self.hash_stash.extend_from_slice(&data[l..]);
+            } else if self.template.typ() == SignatureType::Text {
+                crate::parse::hash_update_text(&mut self.hash, data);
             } else {
-                if self.template.typ() == SignatureType::Text {
-                    crate::parse::hash_update_text(&mut self.hash, data);
-                } else {
-                    self.hash.update(data);
-                }
+                self.hash.update(data);
             }
             self.position += amount as u64;
         }
diff --git a/sq/src/commands/dump.rs b/sq/src/commands/dump.rs
index 3c1eda31..c2d0aa03 100644
--- a/sq/src/commands/dump.rs
+++ b/sq/src/commands/dump.rs
@@ -225,14 +225,12 @@ impl PacketDumper {
         if self.root.is_none() {
             assert_eq!(depth, 0);
             self.root = Some(node);
+        } else if depth == 0 {
+            let root = self.root.take().unwrap();
+            self.dump_tree(output, "", &root)?;
+            self.root = Some(node);
         } else {
-            if depth == 0 {
-                let root = self.root.take().unwrap();
-                self.dump_tree(output, "", &root)?;
-                self.root = Some(node);
-            } else {
-                self.root.as_mut().unwrap().append(depth - 1, node);
-            }
+            self.root.as_mut().unwrap().append(depth - 1, node);
         }
         Ok(())
     }
diff --git a/sq/src/sq.rs b/sq/src/sq.rs
index 37146bcc..e2ed3130 100644
--- a/sq/src/sq.rs
+++ b/sq/src/sq.rs
@@ -715,10 +715,8 @@ fn parse_iso8601(s: &str, pad_date_with: chrono::NaiveTime)
             if let Ok(d) = DateTime::parse_from_str(s, *f) {
                 return Ok(d.into());
             }
-        } else {
-            if let Ok(d) = chrono::NaiveDateTime::parse_from_str(s, *f) {
-                return Ok(DateTime::from_utc(d, Utc));
-            }
+        } else if let Ok(d) = chrono::NaiveDateTime::parse_from_str(s, *f) {
+            return Ok(DateTime::from_utc(d, Utc));
         }
     }
     for f in &[