Fix most clippy lints, take more refeernces

Fix clippy lints and subsequently accept references for more function
parameters.

5 files changed, 38 insertions, 31 deletions

diff --git a/src/framework/standard/args.rs b/src/framework/standard/args.rs
index e9c6365..f18b012 100644
--- a/src/framework/standard/args.rs
+++ b/src/framework/standard/args.rs
@@ -55,7 +55,7 @@ fn second_quote_occurence(s: &str) -> Option<usize> {
     s.chars().enumerate().filter(|&(_, c)| c == '"').nth(1).map(|(pos, _)| pos)
 }
 
-fn parse_quotes<T: FromStr>(s: &mut String, delimiter: &str) -> Result<T, T::Err> 
+fn parse_quotes<T: FromStr>(s: &mut String, delimiter: &str) -> Result<T, T::Err>
     where T::Err: StdError {
 
     // Fall back to `parse` if there're no quotes at the start.
@@ -63,28 +63,28 @@ fn parse_quotes<T: FromStr>(s: &mut String, delimiter: &str) -> Result<T, T::Err
         return parse::<T>(s, delimiter);
     }
 
-    let mut pos = second_quote_occurence(&s).unwrap_or(s.len());
+    let mut pos = second_quote_occurence(s).unwrap_or_else(|| s.len());
     let res = (&s[1..pos]).parse::<T>().map_err(Error::Parse);
     // +1 is for the quote
     if pos < s.len() {
         pos += 1;
     }
-    
+
     s.drain(..pos);
 
     res
 }
 
-fn parse<T: FromStr>(s: &mut String, delimiter: &str) -> Result<T, T::Err> 
+fn parse<T: FromStr>(s: &mut String, delimiter: &str) -> Result<T, T::Err>
     where T::Err: StdError {
-    let mut pos = s.find(delimiter).unwrap_or(s.len());
+    let mut pos = s.find(delimiter).unwrap_or_else(|| s.len());
 
     let res = (&s[..pos]).parse::<T>().map_err(Error::Parse);
     // +1 is for the delimiter
     if pos < s.len() {
         pos += 1;
     }
-    
+
     s.drain(..pos);
     res
 }
@@ -100,7 +100,7 @@ pub struct Args {
 }
 
 impl Args {
-    pub fn new(message: &str, possible_delimiters: Vec<String>) -> Self {
+    pub fn new(message: &str, possible_delimiters: &[String]) -> Self {
         let delimiter = possible_delimiters
             .iter()
             .find(|&d| message.contains(d))
@@ -145,7 +145,10 @@ impl Args {
             return Err(Error::Eos);
         }
 
-        let pos = self.message.find(&self.delimiter).unwrap_or(self.message.len());
+        let pos = self
+            .message
+            .find(&self.delimiter)
+            .unwrap_or_else(|| self.message.len());
 
         fn parse_then_remove(msg: &mut String, pos: usize) -> &str {
             struct ParseThenRemove<'a>(&'a mut String, usize);
@@ -355,7 +358,7 @@ impl Args {
         }
 
         // TODO: Make this efficient
-        
+
         let pos = self.message
             .split(&self.delimiter)
             .position(|e| e.parse::<T>().is_ok());
diff --git a/src/framework/standard/command.rs b/src/framework/standard/command.rs
index be0196c..5138596 100644
--- a/src/framework/standard/command.rs
+++ b/src/framework/standard/command.rs
@@ -13,7 +13,7 @@ pub type Check = Fn(&mut Context, &Message, &mut Args, &CommandOptions) -> bool
                      + Sync
                      + 'static;
 
-pub type HelpFunction = fn(&mut Context, &Message, &HelpOptions, HashMap<String, Arc<CommandGroup>>, Args)
+pub type HelpFunction = fn(&mut Context, &Message, &HelpOptions, HashMap<String, Arc<CommandGroup>>, &Args)
                    -> Result<(), Error>;
 
 pub struct Help(pub HelpFunction, pub Arc<HelpOptions>);
@@ -25,7 +25,7 @@ impl Debug for Help {
 }
 
 impl HelpCommand for Help {
-    fn execute(&self, c: &mut Context, m: &Message, ho: &HelpOptions,hm: HashMap<String, Arc<CommandGroup>>, a: Args) -> Result<(), Error> {
+    fn execute(&self, c: &mut Context, m: &Message, ho: &HelpOptions,hm: HashMap<String, Arc<CommandGroup>>, a: &Args) -> Result<(), Error> {
         (self.0)(c, m, ho, hm, a)
     }
 }
@@ -176,7 +176,7 @@ pub struct HelpOptions {
 }
 
 pub trait HelpCommand: Send + Sync + 'static {
-    fn execute(&self, &mut Context, &Message, &HelpOptions, HashMap<String, Arc<CommandGroup>>, Args) -> Result<(), Error>;
+    fn execute(&self, &mut Context, &Message, &HelpOptions, HashMap<String, Arc<CommandGroup>>, &Args) -> Result<(), Error>;
 
     fn options(&self) -> Arc<CommandOptions> {
         Arc::clone(&DEFAULT_OPTIONS)
@@ -184,7 +184,7 @@ pub trait HelpCommand: Send + Sync + 'static {
 }
 
 impl HelpCommand for Arc<HelpCommand> {
-    fn execute(&self, c: &mut Context, m: &Message, ho: &HelpOptions, hm: HashMap<String, Arc<CommandGroup>>, a: Args) -> Result<(), Error> {
+    fn execute(&self, c: &mut Context, m: &Message, ho: &HelpOptions, hm: HashMap<String, Arc<CommandGroup>>, a: &Args) -> Result<(), Error> {
         (**self).execute(c, m, ho, hm, a)
     }
 }
diff --git a/src/framework/standard/create_help_command.rs b/src/framework/standard/create_help_command.rs
index a8e8704..7e4c338 100644
--- a/src/framework/standard/create_help_command.rs
+++ b/src/framework/standard/create_help_command.rs
@@ -173,6 +173,7 @@ impl CreateHelpCommand {
     /// Finishes the creation of a help-command, returning `Help`.
     /// If `Some(String)` was set as `striked_commands_tip` and the `String` is empty,
     /// the creator will substitute content based on the `HelpBehaviour`-settings.
+    #[cfg_attr(feature = "cargo-clippy", allow(useless_if_let_seq))]
     pub(crate) fn finish(self) -> Arc<Help> {
         if self.0.striked_commands_tip == Some(String::new()) {
             let mut strike_text = String::from("~~`Striked commands`~~ are unavailable because they");
@@ -210,4 +211,4 @@ impl CreateHelpCommand {
 
         Arc::new(Help(function, Arc::new(options)))
     }
-}
\ No newline at end of file
+}
diff --git a/src/framework/standard/help_commands.rs b/src/framework/standard/help_commands.rs
index 85debc4..c660209 100644
--- a/src/framework/standard/help_commands.rs
+++ b/src/framework/standard/help_commands.rs
@@ -28,6 +28,7 @@ use framework::standard::{has_correct_roles, has_correct_permissions};
 use model::channel::Message;
 use model::id::ChannelId;
 use std::collections::HashMap;
+use std::hash::BuildHasher;
 use std::sync::Arc;
 use std::fmt::Write;
 use super::command::{InternalCommand};
@@ -91,12 +92,13 @@ pub fn has_all_requirements(cmd: &Arc<CommandOptions>, msg: &Message) -> bool {
 /// client.with_framework(StandardFramework::new()
 ///     .help(help_commands::with_embeds));
 /// ```
-pub fn with_embeds(_: &mut Context,
-                   msg: &Message,
-                   help_options: &HelpOptions,
-                   groups: HashMap<String, Arc<CommandGroup>>,
-                   args: Args)
-                   -> Result<(), CommandError> {
+pub fn with_embeds<H: BuildHasher>(
+    _: &mut Context,
+    msg: &Message,
+    help_options: &HelpOptions,
+    groups: HashMap<String, Arc<CommandGroup>, H>,
+    args: &Args
+) -> Result<(), CommandError> {
     if !args.is_empty() {
         let name = args.full();
 
@@ -151,7 +153,7 @@ pub fn with_embeds(_: &mut Context,
 
                 let _ = msg.channel_id.send_message(|m| {
                     m.embed(|e| {
-                        let mut embed = e.colour(help_options.embed_success_colour.clone()).title(command_name.clone());
+                        let mut embed = e.colour(help_options.embed_success_colour).title(command_name.clone());
 
                         if let Some(ref desc) = command.desc {
                             embed = embed.description(desc);
@@ -197,7 +199,7 @@ pub fn with_embeds(_: &mut Context,
             }
         }
 
-        let error_msg = help_options.command_not_found_text.replace("{}", &name);
+        let error_msg = help_options.command_not_found_text.replace("{}", name);
         error_embed(&msg.channel_id, &error_msg, help_options.embed_error_colour);
 
         return Ok(());
@@ -304,12 +306,13 @@ pub fn with_embeds(_: &mut Context,
 /// client.with_framework(StandardFramework::new()
 ///     .help(help_commands::plain));
 /// ```
-pub fn plain(_: &mut Context,
-             msg: &Message,
-             help_options: &HelpOptions,
-             groups: HashMap<String, Arc<CommandGroup>>,
-             args: Args)
-             -> Result<(), CommandError> {
+pub fn plain<H: BuildHasher>(
+    _: &mut Context,
+    msg: &Message,
+    help_options: &HelpOptions,
+    groups: HashMap<String, Arc<CommandGroup>, H>,
+    args: &Args
+) -> Result<(), CommandError> {
     if !args.is_empty() {
         let name = args.full();
 
@@ -406,7 +409,7 @@ pub fn plain(_: &mut Context,
         }
 
         let _ = msg.channel_id
-            .say(&help_options.suggestion_text.replace("{}", &name));
+            .say(&help_options.suggestion_text.replace("{}", name));
 
         return Ok(());
     }
diff --git a/src/framework/standard/mod.rs b/src/framework/standard/mod.rs
index 576f820..02de3c0 100644
--- a/src/framework/standard/mod.rs
+++ b/src/framework/standard/mod.rs
@@ -973,7 +973,7 @@ impl Framework for StandardFramework {
                         let mut content = message.content[position..].trim();
                         content = content[command_length..].trim();
 
-                        Args::new(&content, self.configuration.delimiters.clone())
+                        Args::new(content, &self.configuration.delimiters)
                     };
 
                     let before = self.before.clone();
@@ -994,7 +994,7 @@ impl Framework for StandardFramework {
                                     }
                                 }
 
-                                let result = (help.0)(&mut context, &message, &help.1, groups, args);
+                                let result = (help.0)(&mut context, &message, &help.1, groups, &args);
 
                                 if let Some(after) = after {
                                     (after)(&mut context, &message, &built, result);