From a918eb4e507f8a4d83f6151a17db2c982339ab5b Mon Sep 17 00:00:00 2001
From: p0lunin <dmytro.polunin@gmail.com>
Date: Mon, 1 Jun 2020 22:33:51 +0300
Subject: [PATCH] refactoring + fmt

---
 src/command.rs                              |  2 +-
 src/{enum_attributes.rs => command_enum.rs} |  0
 src/fields_parse.rs                         | 42 +++++++++++++--------
 src/lib.rs                                  | 12 +++---
 4 files changed, 33 insertions(+), 23 deletions(-)
 rename src/{enum_attributes.rs => command_enum.rs} (100%)

diff --git a/src/command.rs b/src/command.rs
index fd201f4f..8a5f3a3a 100644
--- a/src/command.rs
+++ b/src/command.rs
@@ -1,4 +1,4 @@
-use crate::enum_attributes::CommandEnum;
+use crate::command_enum::CommandEnum;
 use crate::fields_parse::ParserType;
 use crate::{
     attr::{Attr, BotCommandAttribute},
diff --git a/src/enum_attributes.rs b/src/command_enum.rs
similarity index 100%
rename from src/enum_attributes.rs
rename to src/command_enum.rs
diff --git a/src/fields_parse.rs b/src/fields_parse.rs
index e06f421a..3b38c38f 100644
--- a/src/fields_parse.rs
+++ b/src/fields_parse.rs
@@ -2,7 +2,7 @@ extern crate quote;
 
 use quote::__private::Span;
 use quote::{quote, ToTokens};
-use syn::{FieldsUnnamed, FieldsNamed};
+use syn::{FieldsNamed, FieldsUnnamed};
 
 #[derive(Debug)]
 pub enum ParserType {
@@ -58,41 +58,51 @@ pub fn impl_parse_args_named(
     res
 }
 
-
 fn create_parser(parser_type: &ParserType, count_args: usize) -> quote::__private::TokenStream {
     let function_to_parse = match parser_type {
-        ParserType::Default => {
-            match count_args {
-                1 => {
-                    quote! { (|s: String| Ok((FromStr::from_str(&s).map_err(|_|ParseError::UncorrectFormat)?,)) ) }
-                }
-                _ => quote! { compile_error!("Expected 1 argument") },
+        ParserType::Default => match count_args {
+            1 => {
+                quote! { (|s: String| Ok((FromStr::from_str(&s).map_err(|_|ParseError::IncorrectFormat)?,)) ) }
             }
+            _ => quote! { compile_error!("Expected 1 argument") },
+        },
+        ParserType::Split { separator } => {
+            parser_with_separator(&separator.clone().unwrap_or(" ".to_owned()), count_args)
         }
-        ParserType::Split { separator } => parser_with_separator(
-            &separator.clone().unwrap_or(" ".to_owned()),
-            count_args,
-        ),
         ParserType::Custom(s) => {
             let ident = syn::Ident::new(&s, Span::call_site());
             quote! { #ident }
         }
     };
-    quote! { let arguments = #function_to_parse(args)?; }
+    quote! {
+        let arguments = #function_to_parse(args)?;
+    }
 }
 
 fn parser_with_separator(separator: &str, count_args: usize) -> quote::__private::TokenStream {
-    let inner = quote! { let splited = s.split(#separator).collect::<Vec<_>>(); };
+    let inner = quote! { let mut splited = s.split(#separator); };
     let mut inner2 = quote! {};
     for i in 0..count_args {
         inner2.extend(
-            quote! { FromStr::from_str(splited[#i]).map_err(|_|ParseError::UncorrectFormat)?, },
+            quote! { FromStr::from_str(splited.next().ok_or(ParseError::TooFewArguments {
+                expected: #count_args,
+                found: #i,
+                message: format!("Expected but not found arg number {}", #i + 1),
+            })?).map_err(|_|ParseError::IncorrectFormat)?, },
         )
     }
     let res = quote! {
         (|s: String| {
             #inner
-            Ok((#inner2))
+            let res = (#inner2);
+            match splited.next() {
+                Some(d) => Err(ParseError::TooManyArguments {
+                    expected: #count_args,
+                    found: #count_args + 1,
+                    message: format!("Excess argument: {}", d),
+                }),
+                None => Ok(res)
+            }
         })
     };
     res
diff --git a/src/lib.rs b/src/lib.rs
index aba3f73b..ad083f9b 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,17 +1,17 @@
 mod attr;
 mod command;
-mod enum_attributes;
+mod command_enum;
 mod fields_parse;
 mod rename_rules;
 
 extern crate proc_macro;
 extern crate quote;
 extern crate syn;
-use crate::fields_parse::{impl_parse_args_unnamed, impl_parse_args_named};
+use crate::fields_parse::{impl_parse_args_named, impl_parse_args_unnamed};
 use crate::{
     attr::{Attr, VecAttrs},
     command::Command,
-    enum_attributes::CommandEnum,
+    command_enum::CommandEnum,
 };
 use proc_macro::TokenStream;
 use quote::{quote, ToTokens};
@@ -129,8 +129,8 @@ fn impl_parse(
          {
               use std::str::FromStr;
               let mut words = s.splitn(2, ' ');
-              let mut splited = words.next().ok_or(ParseError::UncorrectFormat)?.split('@');
-              let command_raw = splited.next().ok_or(ParseError::UncorrectFormat)?;
+              let mut splited = words.next().expect("First item will be always.").split('@');
+              let command_raw = splited.next().expect("First item will be always.");
               let bot = splited.next();
               let bot_name = bot_name.into();
               match bot {
@@ -143,7 +143,7 @@ fn impl_parse(
                    #(
                         #matching_values => Ok(#variants_initialization),
                    )*
-                   _ => Err(ParseError::UncorrectCommand(command_raw.to_string())),
+                   _ => Err(ParseError::UnknownCommand(command_raw.to_string())),
               }
          }
     }