make naming more consistent

Author: rushmorem

src/dns.rs

@@ -26,19 +26,33 @@ impl<'a> Name<'a> {
         self.full
     }
 
+    fn without_suffix(&self) -> Option<&str> {
+        let domain_len = self.full.len();
+        let suffix_len = self.suffix()?.len();
+        if domain_len == suffix_len {
+            return None;
+        }
+        self.full.get(..domain_len - suffix_len - 1)
+    }
+
     /// The root domain (the registrable part)
     pub fn root(&self) -> Option<&str> {
-        let offset = self.prefix()?.rfind('.').map(|x| x + 1).unwrap_or_default();
+        let offset = self
+            .without_suffix()?
+            .rfind('.')
+            .map(|x| x + 1)
+            .unwrap_or_default();
         self.full.get(offset..)
     }
 
-    fn prefix(&self) -> Option<&str> {
+    /// The part before the root domain (aka. subdomain)
+    pub fn prefix(&self) -> Option<&str> {
         let domain_len = self.full.len();
-        let suffix_len = self.suffix()?.len();
-        if domain_len == suffix_len {
+        let root_len = self.root()?.len();
+        if domain_len == root_len {
             return None;
         }
-        self.full.get(..domain_len - suffix_len - 1)
+        self.full.get(..domain_len - root_len - 1)
     }
 
     /// The domain name suffix (extension)

src/domain.rs

@@ -35,13 +35,27 @@ impl<'a> Name<'a> {
         self.full
     }
 
+    fn without_suffix(&self) -> Option<&str> {
+        let domain_len = self.full.len();
+        let suffix_len = self.suffix().len();
+        if domain_len == suffix_len {
+            return None;
+        }
+        self.full.get(..domain_len - suffix_len - 1)
+    }
+
     /// The root domain (the registrable part)
     pub fn root(&self) -> Option<&str> {
-        let offset = self.prefix()?.rfind('.').map(|x| x + 1).unwrap_or_default();
+        let offset = self
+            .without_suffix()?
+            .rfind('.')
+            .map(|x| x + 1)
+            .unwrap_or_default();
         self.full.get(offset..)
     }
 
-    pub fn sub_domain(&self) -> Option<&str> {
+    /// The part before the root domain (aka. subdomain)
+    pub fn prefix(&self) -> Option<&str> {
         let domain_len = self.full.len();
         let root_len = self.root()?.len();
         if domain_len == root_len {
@@ -50,15 +64,6 @@ impl<'a> Name<'a> {
         self.full.get(..domain_len - root_len - 1)
     }
 
-    fn prefix(&self) -> Option<&str> {
-        let domain_len = self.full.len();
-        let suffix_len = self.suffix().len();
-        if domain_len == suffix_len {
-            return None;
-        }
-        self.full.get(..domain_len - suffix_len - 1)
-    }
-
     /// The domain name suffix (extension)
     pub fn suffix(&self) -> &str {
         let offset = self.full.len() - self.suffix.as_bytes().len();