refactor: use error type instead of unit

src/data_centers.rs

@@ -1,3 +1,5 @@
+use errors::UnknownVariant;
+
 use std::fmt::{Display, Formatter, Result as FmtResult};
 use std::str::FromStr;
 
@@ -34,7 +36,7 @@ impl DataCenter {
 }
 
 impl FromStr for DataCenter {
-  type Err = ();
+  type Err = UnknownVariant;
 
   fn from_str(s: &str) -> Result<Self, Self::Err> {
     let data_center = match s.to_lowercase().as_str() {
@@ -44,7 +46,7 @@ impl FromStr for DataCenter {
       "gaia" => DataCenter::Gaia,
       "mana" => DataCenter::Mana,
       "primal" => DataCenter::Primal,
-      _ => return Err(())
+      _ => return Err(UnknownVariant("DataCenter", s.into()))
     };
 
     Ok(data_center)

src/errors.rs

@@ -0,0 +1,10 @@
+use std::fmt::{Display, Formatter, Result as FmtResult};
+
+#[derive(Debug)]
+pub struct UnknownVariant(pub &'static str, pub String);
+
+impl Display for UnknownVariant {
+  fn fmt(&self, f: &mut Formatter) -> FmtResult {
+    write!(f, "unknown variant {} for type {}", self.1, self.0)
+  }
+}

src/jobs.rs

@@ -1,3 +1,4 @@
+use errors::UnknownVariant;
 use roles::Role;
 
 use std::fmt::{Display, Formatter, Result as FmtResult};
@@ -97,7 +98,7 @@ impl Job {
 }
 
 impl FromStr for Job {
-  type Err = ();
+  type Err = UnknownVariant;
 
   fn from_str(s: &str) -> Result<Self, Self::Err> {
     let job = match s.to_lowercase().as_str() {
@@ -119,7 +120,7 @@ impl FromStr for Job {
       "paladin" | "pld" => Job::Paladin,
       "warrior" | "war" => Job::Warrior,
 
-      _ => return Err(())
+      _ => return Err(UnknownVariant("Job", s.into()))
     };
 
     Ok(job)

src/lib.rs

@@ -1,4 +1,5 @@
 pub mod data_centers;
+pub mod errors;
 pub mod jobs;
 pub mod roles;
 pub mod worlds;

src/roles.rs

@@ -1,3 +1,5 @@
+use errors::UnknownVariant;
+
 use std::fmt::{Display, Formatter, Result as FmtResult};
 use std::str::FromStr;
 
@@ -21,14 +23,14 @@ impl Role {
 }
 
 impl FromStr for Role {
-  type Err = ();
+  type Err = UnknownVariant;
 
   fn from_str(s: &str) -> Result<Self, Self::Err> {
     let role = match s.to_lowercase().as_str() {
       "dps" => Role::Dps,
       "healer" => Role::Healer,
       "tank" => Role::Tank,
-      _ => return Err(())
+      _ => return Err(UnknownVariant("Role", s.into()))
     };
 
     Ok(role)

src/worlds.rs

@@ -1,4 +1,5 @@
 use data_centers::DataCenter;
+use errors::UnknownVariant;
 
 use std::fmt::{Display, Formatter, Result as FmtResult};
 use std::str::FromStr;
@@ -322,7 +323,7 @@ impl World {
 }
 
 impl FromStr for World {
-  type Err = ();
+  type Err = UnknownVariant;
 
   fn from_str(s: &str) -> Result<Self, Self::Err> {
     let world = match s.to_lowercase().as_str() {
@@ -398,7 +399,7 @@ impl FromStr for World {
       "malboro" => World::Malboro,
       "ultros" => World::Ultros,
 
-      _ => return Err(())
+      _ => return Err(UnknownVariant("World", s.into()))
     };
 
     Ok(world)