Merge pull request #8 from jonhteper/master

Implement Display trait & unify TryFrom implementations

Author: MidasLamb

src/lib.rs

@@ -10,6 +10,7 @@ mod test_readme {
     mod something {}
 }
 
+use std::fmt::Display;
 use delegate::delegate;
 
 #[cfg(feature = "serde")]
@@ -115,51 +116,56 @@ impl NonEmptyString {
     }
 }
 
-impl std::convert::AsRef<str> for NonEmptyString {
+impl AsRef<str> for NonEmptyString {
     fn as_ref(&self) -> &str {
         &self.0
     }
 }
 
-impl std::convert::AsRef<String> for NonEmptyString {
+impl AsRef<String> for NonEmptyString {
     fn as_ref(&self) -> &String {
         &self.0
     }
 }
 
-impl<'s> std::convert::TryFrom<&'s str> for NonEmptyString {
-    type Error = ();
+impl<'s> TryFrom<&'s str> for NonEmptyString {
+    type Error = &'s str;
 
     fn try_from(value: &'s str) -> Result<Self, Self::Error> {
         if value.is_empty() {
-            Err(())
-        } else {
-            Ok(NonEmptyString::new(value.to_owned()).expect("Value is not empty"))
+            return Err(value);
         }
+            
+        Ok(NonEmptyString(value.to_owned()))
     }
 }
 
-impl std::convert::TryFrom<String> for NonEmptyString {
+impl TryFrom<String> for NonEmptyString {
     type Error = String;
 
     fn try_from(value: String) -> Result<Self, Self::Error> {
         NonEmptyString::new(value)
     }
 }
 
+impl Display for NonEmptyString {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        Display::fmt(&self.0, f)
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
-    use assert_matches::assert_matches;
 
     #[test]
-    fn empty_string_returns_none() {
+    fn empty_string_returns_err() {
         assert_eq!(NonEmptyString::new("".to_owned()), Err("".to_owned()));
     }
 
     #[test]
-    fn non_empty_string_returns_some() {
-        assert_matches!(NonEmptyString::new("string".to_owned()), Ok(_));
+    fn non_empty_string_returns_ok() {
+        assert!(NonEmptyString::new("string".to_owned()).is_ok())
     }
 
     #[test]
@@ -192,4 +198,11 @@ mod tests {
         // `len` is a `String` method.
         assert!(nes.len() > 0);
     }
+
+    #[test]
+    fn format_test() {
+        let str = NonEmptyString::new("string".to_owned()).unwrap();
+        println!("{}", &str);
+        assert_eq!(String::from("string"), str.to_string())
+    }
 }