introduce a throw! macro and use it.

src/config.rs

@@ -74,7 +74,7 @@ pub fn init() -> Result<Config, Vec<&'static str>> {
         let db_pool_size = vars.remove(DB_POOL_SIZE).unwrap();
         let db_pool_size = match db_pool_size.parse::<u32>() {
             Ok(size) => size,
-            Err(_) => return Err(vec![DB_POOL_SIZE]),
+            Err(_) => throw!(vec![DB_POOL_SIZE]),
         };
 
         let gh_token = vars.remove(GITHUB_TOKEN).unwrap();
@@ -83,13 +83,13 @@ pub fn init() -> Result<Config, Vec<&'static str>> {
         let gh_interval = vars.remove(GITHUB_INTERVAL).unwrap();
         let gh_interval = match gh_interval.parse::<u64>() {
             Ok(interval) => interval,
-            Err(_) => return Err(vec![GITHUB_INTERVAL]),
+            Err(_) => throw!(vec![GITHUB_INTERVAL]),
         };
 
         let post_comments = vars.remove(POST_COMMENTS).unwrap();
         let post_comments = match post_comments.parse::<bool>() {
             Ok(pc) => pc,
-            Err(_) => return Err(vec![POST_COMMENTS]),
+            Err(_) => throw!(vec![POST_COMMENTS]),
         };
 
         let webhook_secrets = vars.remove(GITHUB_WEBHOOK_SECRETS).unwrap();
@@ -106,11 +106,9 @@ pub fn init() -> Result<Config, Vec<&'static str>> {
            })
 
     } else {
-
         Err(vars.iter()
                 .filter(|&(_, v)| v.is_err())
                 .map(|(&k, _)| k)
                 .collect())
-
     }
 }

src/github/client.rs

@@ -43,6 +43,12 @@ pub struct Client {
     rate_limit_timeout: DateTime<Utc>,
 }
 
+fn read_to_string<R: Read>(reader: &mut R) -> DashResult<String> {    
+    let mut string = String::new();
+    reader.read_to_string(&mut string)?;
+    Ok(string)
+}
+
 impl Client {
     pub fn new() -> Self {
         let tls_connector = HttpsConnector::new(NativeTlsClient::new().unwrap());
@@ -72,7 +78,7 @@ impl Client {
                     }
                 }
             }
-            return Err(DashError::Misc(None));
+            throw!(DashError::Misc(None))
 
         }
         Ok(repos)
@@ -129,7 +135,7 @@ impl Client {
             let mut res = try!(self.get(url, None));
             self.deserialize(&mut res)
         } else {
-            Err(DashError::Misc(None))
+            throw!(DashError::Misc(None))
         }
     }
 
@@ -165,13 +171,11 @@ impl Client {
 
         let mut res = self.patch(&url, &payload)?;
 
-        if let StatusCode::Ok = res.status {
-            Ok(())
-        } else {
-            let mut body = String::new();
-            res.read_to_string(&mut body)?;
-            Err(DashError::Misc(Some(body)))
+        if StatusCode::Ok != res.status {
+            throw!(DashError::Misc(Some(read_to_string(&mut res)?)))
         }
+
+        Ok(())
     }
 
     pub fn add_label(&self, repo: &str, issue_num: i32, label: &str) -> DashResult<()> {
@@ -180,13 +184,11 @@ impl Client {
 
         let mut res = self.post(&url, &payload)?;
 
-        if let StatusCode::Ok = res.status {
-            Ok(())
-        } else {
-            let mut body = String::new();
-            res.read_to_string(&mut body)?;
-            Err(DashError::Misc(Some(body)))
+        if StatusCode::Ok != res.status {
+            throw!(DashError::Misc(Some(read_to_string(&mut res)?)))
         }
+
+        Ok(())
     }
 
     pub fn remove_label(&self, repo: &str, issue_num: i32, label: &str) -> DashResult<()> {
@@ -197,13 +199,11 @@ impl Client {
                           label);
         let mut res = self.delete(&url)?;
 
-        if let StatusCode::NoContent = res.status {
-            Ok(())
-        } else {
-            let mut body = String::new();
-            res.read_to_string(&mut body)?;
-            Err(DashError::Misc(Some(body)))
+        if StatusCode::NoContent != res.status {
+            throw!(DashError::Misc(Some(read_to_string(&mut res)?)))
         }
+
+        Ok(())
     }
 
     pub fn new_comment(&self,
@@ -287,7 +287,7 @@ impl Client {
             Ok(m) => Ok(m),
             Err(why) => {
                 error!("Unable to parse from JSON ({:?}): {}", why, buf);
-                Err(why.into())
+                throw!(why)
             }
         }
     }

src/github/mod.rs

@@ -155,7 +155,7 @@ pub fn handle_comment(conn: &PgConnection, comment: CommentFromJson, repo: &str)
 
         if let Err(why) = nag::update_nags(&comment) {
             error!("Problem updating FCPs: {:?}", &why);
-            return Err(why);
+            throw!(why);
         }
     }
 

src/github/nag.rs

@@ -199,7 +199,7 @@ fn evaluate_nags() -> DashResult<()> {
         Ok(p) => p,
         Err(why) => {
             error!("Unable to retrieve list of pending proposals: {:?}", why);
-            return Err(why.into());
+            throw!(why);
         }
     };
 
@@ -371,7 +371,7 @@ fn evaluate_nags() -> DashResult<()> {
         Err(why) => {
             error!("Unable to retrieve FCPs that need to be marked as finished: {:?}",
                    why);
-            return Err(why.into());
+            throw!(why);
         }
     };
 
@@ -634,12 +634,12 @@ impl FcpDisposition {
     }
 
     pub fn from_str(string: &str) -> DashResult<Self> {
-        match string {
-            FCP_REPR_MERGE => Ok(FcpDisposition::Merge),
-            FCP_REPR_CLOSE => Ok(FcpDisposition::Close),
-            FCP_REPR_POSTPONE => Ok(FcpDisposition::Postpone),
-            _ => Err(DashError::Misc(None)),
-        }
+        Ok(match string {
+            FCP_REPR_MERGE => FcpDisposition::Merge,
+            FCP_REPR_CLOSE => FcpDisposition::Close,
+            FCP_REPR_POSTPONE => FcpDisposition::Postpone,
+            _ => throw!(DashError::Misc(None)),
+        })
     }
 
     pub fn label(self) -> Label {
@@ -701,7 +701,7 @@ fn parse_fcp_subcommand<'a>(
         },
 
         _ => {
-            Err(DashError::Misc(if fcp_context {
+            throw!(DashError::Misc(if fcp_context {
                 error!("unrecognized subcommand for fcp: {}", subcommand);
                 Some(format!("found bad subcommand: {}", subcommand))
             } else {
@@ -987,7 +987,7 @@ impl<'a> RfcBotCommand<'a> {
                         .ok_or_else(|| DashError::Misc(Some("no user specified".to_string())))?;
 
                 if user.is_empty() {
-                    return Err(DashError::Misc(Some("no user specified".to_string())));
+                    throw!(DashError::Misc(Some("no user specified".to_string())));
                 }
 
                 Ok(RfcBotCommand::FeedbackRequest(&user[1..]))
@@ -1191,14 +1191,14 @@ impl<'a> RfcBotComment<'a> {
                       self.issue.repository,
                       self.issue.number);
 
-                Err(DashError::Misc(None))
+                throw!(DashError::Misc(None))
             }
 
         } else {
             info!("Skipping comment to {}#{}, comment posts are disabled.",
                   self.issue.repository,
                   self.issue.number);
-            Err(DashError::Misc(None))
+            throw!(DashError::Misc(None))
         }
     }
 }

src/macros.rs

@@ -0,0 +1,5 @@
+macro_rules! throw {
+    ($err: expr) => {
+        Err::<!, _>($err)?
+    };
+}

src/main.rs

@@ -31,6 +31,9 @@ extern crate toml;
 extern crate url;
 extern crate urlencoded;
 
+#[macro_use]
+mod macros;
+
 mod config;
 mod domain;
 mod error;

src/teams.rs

@@ -127,7 +127,7 @@ impl Team {
                     .first::<GitHubUser>(conn)
             {
                 error!("unable to find {} in database: {:?}", member_login, why);
-                return Err(why.into());
+                throw!(why);
             }
         }