Fix warnings

src/urlencoded/de.rs

@@ -133,9 +133,9 @@ impl<'de> de::Deserializer<'de> for Deserializer<'de> {
             map.push_back((*field, values));
         }
         let parts = fields
-            .into_iter()
+            .iter()
             .map(|f| Part(Cow::Borrowed(f), None))
-            .zip(PartIterator(self.parser).into_iter().map(|(_, mut v)| {
+            .zip(PartIterator(self.parser).map(|(_, mut v)| {
                 if let Some((_, val)) = map.pop_front() {
                     v.1 = Some(val);
                 }
@@ -263,7 +263,7 @@ impl<'de> de::Deserializer<'de> for Part<'de> {
     where
         V: de::Visitor<'de>,
     {
-        let iter = self.1.ok_or(Error::custom("expected sequence"))?;
+        let iter = self.1.ok_or_else(|| Error::custom("expected sequence"))?;
         visitor.visit_seq(SeqDeserializer::new(
             iter.into_iter().map(|v| Part(v, None)),
         ))

src/urlencoded/ser.rs

@@ -54,9 +54,7 @@ impl<'input, 'output, Target: 'output + UrlEncodedTarget>
     pub fn new(
         urlencoder: &'output mut UrlEncodedSerializer<'input, Target>,
     ) -> Self {
-        Serializer {
-            urlencoder: urlencoder,
-        }
+        Serializer { urlencoder }
     }
 }
 
@@ -453,7 +451,7 @@ where
         value: &T,
     ) -> Result<()> {
         {
-            let key = self.key.as_ref().ok_or_else(|| Error::no_key())?;
+            let key = self.key.as_ref().ok_or_else(Error::no_key)?;
             let value_sink = value::ValueSink::new(self.urlencoder, &key);
             value.serialize(part::PartSerializer::new(value_sink))?;
         }

src/urlencoded/ser/key.rs

@@ -38,7 +38,7 @@ where
     End: for<'key> FnOnce(Key<'key>) -> Result<Ok, Error>,
 {
     pub fn new(end: End) -> Self {
-        KeySink { end: end }
+        KeySink { end }
     }
 }
 

src/urlencoded/ser/pair.rs

@@ -251,7 +251,7 @@ where
                 if result.is_ok() {
                     self.state = PairState::Done;
                 } else {
-                    self.state = PairState::WaitingForValue { key: key };
+                    self.state = PairState::WaitingForValue { key };
                 }
                 result
             },

src/urlencoded/ser/part.rs

@@ -1,7 +1,5 @@
 use std::str;
 
-use dtoa;
-use itoa;
 use serde::ser;
 
 use crate::urlencoded::error::Error;
@@ -11,7 +9,7 @@ pub struct PartSerializer<S> {
 
 impl<S: Sink> PartSerializer<S> {
     pub fn new(sink: S) -> Self {
-        PartSerializer { sink: sink }
+        PartSerializer { sink }
     }
 }
 
@@ -111,7 +109,7 @@ impl<S: Sink> ser::Serializer for PartSerializer<S> {
     }
 
     fn serialize_unit_struct(self, name: &'static str) -> Result<S::Ok, Error> {
-        self.sink.serialize_static_str(name.into())
+        self.sink.serialize_static_str(name)
     }
 
     fn serialize_unit_variant(
@@ -120,7 +118,7 @@ impl<S: Sink> ser::Serializer for PartSerializer<S> {
         _variant_index: u32,
         variant: &'static str,
     ) -> Result<S::Ok, Error> {
-        self.sink.serialize_static_str(variant.into())
+        self.sink.serialize_static_str(variant)
     }
 
     fn serialize_newtype_struct<T: ?Sized + ser::Serialize>(