Some clippy fixes

Author: Vincent Prouillet

src/format.rs

@@ -65,7 +65,7 @@ impl<'a> Formatter<'a> {
         self.endline();
     }
     pub fn margin(&mut self) {
-        if self.buf.len() != 0 {
+        if !self.buf.is_empty() {
             self.buf.push('\n');
         }
     }
@@ -105,7 +105,7 @@ impl<'a> Formatter<'a> {
             self.endline();
             self.indent += self.style.indent;
             for line in s.lines() {
-                if line.trim().len() != 0 {
+                if !line.trim().is_empty() {
                     self.indent();
                     self.write(&line.replace(r#"""""#, r#"\""""#));
                 }

src/query_format.rs

@@ -87,7 +87,7 @@ impl Displayable for Selection {
 }
 
 fn format_arguments(arguments: &[(String, Value)], f: &mut Formatter) {
-    if arguments.len() > 0 {
+    if !arguments.is_empty() {
         f.write("(");
         f.write(&arguments[0].0);
         f.write(": ");
@@ -112,7 +112,7 @@ impl Displayable for Field {
         f.write(&self.name);
         format_arguments(&self.arguments, f);
         format_directives(&self.directives, f);
-        if self.selection_set.items.len() > 0 {
+        if !self.selection_set.items.is_empty() {
             f.write(" ");
             f.start_block();
             for item in &self.selection_set.items {
@@ -133,7 +133,7 @@ impl Displayable for Query {
         if let Some(ref name) = self.name {
             f.write(" ");
             f.write(name);
-            if self.variable_definitions.len() > 0 {
+            if !self.variable_definitions.is_empty() {
                 f.write("(");
                 self.variable_definitions[0].display(f);
                 for var in &self.variable_definitions[1..] {
@@ -161,7 +161,7 @@ impl Displayable for Mutation {
         if let Some(ref name) = self.name {
             f.write(" ");
             f.write(name);
-            if self.variable_definitions.len() > 0 {
+            if !self.variable_definitions.is_empty() {
                 f.write("(");
                 for var in &self.variable_definitions {
                     var.display(f);
@@ -187,7 +187,7 @@ impl Displayable for Subscription {
         if let Some(ref name) = self.name {
             f.write(" ");
             f.write(name);
-            if self.variable_definitions.len() > 0 {
+            if !self.variable_definitions.is_empty() {
                 f.write("(");
                 for var in &self.variable_definitions {
                     var.display(f);
@@ -248,7 +248,7 @@ impl Displayable for Value {
             Value::Enum(ref name) => f.write(name),
             Value::List(ref items) => {
                 f.write("[");
-                if items.len() > 0 {
+                if !items.is_empty() {
                     items[0].display(f);
                     for item in &items[1..] {
                         f.write(", ");

src/query_grammar.rs

@@ -112,10 +112,13 @@ pub fn variable_type<'a>(input: &mut TokenStream<'a>)
         .map(Box::new)
         .map(VariableType::ListType))
     .and(optional(punct("!")).map(|v| v.is_some()))
-    .map(|(typ, strict)| match strict {
-        true => VariableType::NonNullType(Box::new(typ)),
-        false => typ,
-    })
+    .map(|(typ, strict)|
+        if strict {
+            VariableType::NonNullType(Box::new(typ))
+        } else {
+            typ
+        }
+    )
     .parse_stream(input)
 }
 
@@ -137,7 +140,7 @@ pub fn float_value<'a>(input: &mut TokenStream<'a>)
 
 fn unquote_string(s: &str) -> Result<String, Error<Token, Token>> {
     let mut res = String::with_capacity(s.len());
-    debug_assert!(s.starts_with("\"") && s.ends_with("\""));
+    debug_assert!(s.starts_with('"') && s.ends_with('"'));
     let mut chars = s[1..s.len()-1].chars();
     while let Some(c) = chars.next() {
         match c {
@@ -161,7 +164,8 @@ fn unquote_string(s: &str) -> Result<String, Error<Token, Token>> {
             c => res.push(c),
         }
     }
-    return Ok(res);
+
+    Ok(res)
 }
 
 fn unquote_block_string(src: &str) -> Result<String, Error<Token, Token>> {
@@ -180,7 +184,7 @@ fn unquote_block_string(src: &str) -> Result<String, Error<Token, Token>> {
     let mut lines = src[3..src.len()-3].lines();
     if let Some(first) = lines.next() {
         let stripped = first.trim();
-        if stripped.len() > 0 {
+        if !stripped.is_empty() {
             result.push_str(stripped);
             result.push('\n');
         }
@@ -193,10 +197,11 @@ fn unquote_block_string(src: &str) -> Result<String, Error<Token, Token>> {
         }
         result.push('\n');
     }
-    if result[last_line..].trim().len() == 0 {
+    if result[last_line..].trim().is_empty() {
         result.truncate(last_line);
     }
-    return Ok(result);
+
+    Ok(result)
 }
 
 pub fn string_value<'a>(input: &mut TokenStream<'a>)

src/tokenizer.rs

@@ -84,26 +84,26 @@ impl<'a> Resetable for TokenStream<'a> {
 // NOTE: we expect that first character is always digit or minus, as returned
 // by tokenizer
 fn check_int(value: &str) -> bool {
-    return value == "0" || value == "-0" ||
+    value == "0" || value == "-0" ||
        (!value.starts_with('0') && value != "-" && !value.starts_with("-0")
-       && value[1..].chars().all(|x| x >= '0' && x <= '9'));
+       && value[1..].chars().all(|x| x >= '0' && x <= '9'))
 }
 
 fn check_dec(value: &str) -> bool {
-    return value.len() > 0 && value.chars().all(|x| x >= '0' && x <= '9');
+    !value.is_empty() && value.chars().all(|x| x >= '0' && x <= '9')
 }
 
 fn check_exp(value: &str) -> bool {
-    return (value.starts_with('-') || value.starts_with('+')) &&
+    (value.starts_with('-') || value.starts_with('+')) &&
         value.len() >= 2 &&
-        value[1..].chars().all(|x| x >= '0' && x <= '9');
+        value[1..].chars().all(|x| x >= '0' && x <= '9')
 }
 
 fn check_float(value: &str, exponent: Option<usize>, real: Option<usize>)
     -> bool
 {
     match (exponent, real) {
-        (Some(e), Some(r)) if e < r => return false,
+        (Some(e), Some(r)) if e < r => false,
         (Some(e), Some(r))
         => check_int(&value[..r]) &&
            check_dec(&value[r+1..e]) &&
@@ -125,8 +125,9 @@ impl<'a> TokenStream<'a> {
             next_state: None,
         };
         me.skip_whitespace();
-        return me;
+        me
     }
+
     fn peek_token(&mut self)
         -> Result<(Kind, usize), Error<Token<'a>, Token<'a>>>
     {
@@ -150,7 +151,7 @@ impl<'a> TokenStream<'a> {
                     return Ok((Punctuator, 3))
                 } else {
                     return Err(Error::unexpected_message(
-                        format_args!("bare dot {:?} is not suppored, \
+                        format_args!("bare dot {:?} is not supported, \
                             only \"...\"", cur_char)));
                 }
             }
@@ -223,7 +224,7 @@ impl<'a> TokenStream<'a> {
                 } else {
                     let mut prev_char = cur_char;
                     let mut nchars = 1;
-                    while let Some((idx, cur_char)) = iter.next() {
+                    for (idx, cur_char) in iter {
                         nchars += 1;
                         match cur_char {
                             '"' if prev_char == '\\' => {}
@@ -250,6 +251,7 @@ impl<'a> TokenStream<'a> {
                 format_args!("unexpected character {:?}", cur_char))),
         }
     }
+
     fn skip_whitespace(&mut self) {
         let mut iter = self.buf[self.off..].char_indices();
         let idx = loop {
@@ -286,6 +288,7 @@ impl<'a> TokenStream<'a> {
         };
         self.off += idx;
     }
+
     fn update_position(&mut self, len: usize) {
         let val = &self.buf[self.off..][..len];
         self.off += len;
@@ -294,7 +297,7 @@ impl<'a> TokenStream<'a> {
         if lines > 0 {
             let line_offset = val.rfind('\n').unwrap()+1;
             let num = val[line_offset..].chars().count();
-            self.position.column = num+1;
+            self.position.column = num + 1;
         } else {
             let num = val.chars().count();
             self.position.column += num;