Auto merge of #269 - frewsxcv:warnings, r=SimonSapin

Fix warnings.

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src/lib.rs

@@ -126,7 +126,7 @@ use parser::{Parser, Context, SchemeType, to_u32};
 use percent_encoding::{PATH_SEGMENT_ENCODE_SET, USERINFO_ENCODE_SET,
                        percent_encode, percent_decode, utf8_percent_encode};
 use std::cmp;
-use std::error::Error;
+#[cfg(feature = "serde")] use std::error::Error;
 use std::fmt::{self, Write};
 use std::hash;
 use std::io;

tests/unit.rs

@@ -123,14 +123,15 @@ fn issue_124() {
 
 #[test]
 fn test_equality() {
-    use std::hash::{Hash, Hasher, SipHasher};
+    use std::hash::{Hash, Hasher};
+    use std::collections::hash_map::DefaultHasher;
 
     fn check_eq(a: &Url, b: &Url) {
         assert_eq!(a, b);
 
-        let mut h1 = SipHasher::new();
+        let mut h1 = DefaultHasher::new();
         a.hash(&mut h1);
-        let mut h2 = SipHasher::new();
+        let mut h2 = DefaultHasher::new();
         b.hash(&mut h2);
         assert_eq!(h1.finish(), h2.finish());
     }