test: improve test coverage

crates/scion/src/address/asn.rs

@@ -34,6 +34,14 @@ impl Asn {
     }
 
     /// Return true for the special 'wildcard' AS number, 0.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// # use scion::address::Asn;
+    /// assert!(Asn::WILDCARD.is_wildcard());
+    /// assert!(!Asn::new(1).is_wildcard());
+    /// ```
     pub fn is_wildcard(&self) -> bool {
         self == &Self::WILDCARD
     }
@@ -120,6 +128,31 @@ impl FromStr for Asn {
 mod tests {
     use super::*;
 
+    mod conversion {
+        use super::*;
+
+        macro_rules! test_success {
+            ($name:ident, $number:expr, $asn:expr) => {
+                #[test]
+                fn $name() {
+                    assert_eq!(Asn::try_from($number).unwrap(), $asn);
+                    assert_eq!(u64::from($asn), $number);
+                }
+            };
+        }
+
+        test_success!(wildcard, 0, Asn::WILDCARD);
+        test_success!(max_value, Asn::MAX_VALUE, Asn(0xffff_ffff_ffff));
+
+        #[test]
+        fn out_of_range() {
+            assert_eq!(
+                Asn::try_from(Asn::MAX_VALUE + 1).unwrap_err(),
+                AddressParseError::AsnOutOfRange
+            );
+        }
+    }
+
     mod parse {
         use super::*;
 

crates/scion/src/address/ia.rs

@@ -32,6 +32,15 @@ impl IA {
     }
 
     /// Return true if either the ISD or AS numbers are wildcards
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// # use scion::address::{Asn,IA,Isd};
+    /// assert!(IA::new(Isd::WILDCARD,Asn::new(1)).is_wildcard());
+    /// assert!(IA::new(Isd::new(1),Asn::WILDCARD).is_wildcard());
+    /// assert!(!IA::new(Isd::new(1),Asn::new(1)).is_wildcard());
+    /// ```
     pub fn is_wildcard(&self) -> bool {
         self.isd().is_wildcard() || self.asn().is_wildcard()
     }
@@ -66,11 +75,10 @@ impl FromStr for IA {
             return Err(Self::Err::InvalidIaString(string.into()));
         }
 
-        if let Some((isd_str, asn_str)) = string.split_once('-') {
-            Ok(IA::new(Isd::from_str(isd_str)?, Asn::from_str(asn_str)?))
-        } else {
-            Err(Self::Err::InvalidIaString(string.into()))
-        }
+        let (isd_str, asn_str) = string
+            .split_once('-')
+            .expect("already checked that the string contains exactly one '-'");
+        Ok(IA::new(Isd::from_str(isd_str)?, Asn::from_str(asn_str)?))
     }
 }
 
@@ -142,9 +150,42 @@ mod tests {
         Asn::new(0xffff_ffff_ffff)
     );
 
+    mod conversion {
+        use super::*;
+
+        #[test]
+        fn as_u64() {
+            assert_eq!(
+                IA::new(Isd::new(0x0123), Asn::new(0x4567_89ab_cdef)).as_u64(),
+                0x0123_4567_89ab_cdef
+            )
+        }
+
+        macro_rules! test_success {
+            ($name:ident, $number:expr, $ia:expr) => {
+                #[test]
+                fn $name() {
+                    assert_eq!(IA::from($number), $ia);
+                    assert_eq!(u64::from($ia), $number);
+                }
+            };
+        }
+
+        test_success!(wildcard, 0, IA::new(Isd::WILDCARD, Asn::WILDCARD));
+        test_success!(max_value, -1_i64 as u64, IA(0xffff_ffff_ffff_ffff));
+    }
+
     mod display {
         use super::*;
 
+        #[test]
+        fn debug() {
+            assert_eq!(
+                format!("{:?}", IA(0x0001_ff00_0000_00ab)),
+                "IA(0x0001ff00000000ab)"
+            );
+        }
+
         #[test]
         fn simple() {
             assert_eq!(IA(0x0001_ff00_0000_00ab).to_string(), "1-ff00:0:ab");
@@ -172,6 +213,7 @@ mod tests {
                 #[test]
                 fn $name() {
                     assert_eq!(IA::from_str($input).unwrap(), $expected);
+                    assert_eq!(IA::try_from($input.to_string()).unwrap(), $expected);
                 }
             };
         }

crates/scion/src/address/isd.rs

@@ -28,7 +28,15 @@ impl Isd {
         self.0
     }
 
-    // Return true for the special 'wildcard' AS number
+    /// Return true for the special 'wildcard' AS number
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// # use scion::address::Isd;
+    /// assert!(Isd::WILDCARD.is_wildcard());
+    /// assert!(!Isd::new(1).is_wildcard());
+    /// ```
     pub fn is_wildcard(&self) -> bool {
         self == &Self::WILDCARD
     }
@@ -54,3 +62,17 @@ impl FromStr for Isd {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    mod display {
+        use super::*;
+
+        #[test]
+        fn wildcard() {
+            assert_eq!(Isd::WILDCARD.to_string(), "0");
+        }
+    }
+}