Use derive for common map trait implementations

Use derive for `Clone`, `Debug`, `PartialEq`, and `Eq`, which all currently definitions identical to the derived versions. The derived versions are now generic over any `<K, V>` pair.

Additionally, use IndexMap::extend in Map::append, to take advantage of reservation logic

src/map.rs

@@ -23,6 +23,7 @@ use alloc::collections::{btree_map, BTreeMap};
 use indexmap::{self, IndexMap};
 
 /// Represents a JSON key/value type.
+#[derive(Debug, Clone, PartialEq, Eq)]
 pub struct Map<K, V> {
     map: MapImpl<K, V>,
 }
@@ -197,9 +198,8 @@ impl Map<String, Value> {
     #[inline]
     pub fn append(&mut self, other: &mut Self) {
         #[cfg(feature = "preserve_order")]
-        for (k, v) in mem::replace(&mut other.map, MapImpl::default()) {
-            self.map.insert(k, v);
-        }
+        self.map
+            .extend(mem::replace(&mut other.map, MapImpl::default()));
         #[cfg(not(feature = "preserve_order"))]
         self.map.append(&mut other.map);
     }
@@ -297,24 +297,6 @@ impl Default for Map<String, Value> {
     }
 }
 
-impl Clone for Map<String, Value> {
-    #[inline]
-    fn clone(&self) -> Self {
-        Map {
-            map: self.map.clone(),
-        }
-    }
-}
-
-impl PartialEq for Map<String, Value> {
-    #[inline]
-    fn eq(&self, other: &Self) -> bool {
-        self.map.eq(&other.map)
-    }
-}
-
-impl Eq for Map<String, Value> {}
-
 /// Access an element of this map. Panics if the given key is not present in the
 /// map.
 ///
@@ -364,13 +346,6 @@ where
     }
 }
 
-impl Debug for Map<String, Value> {
-    #[inline]
-    fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {
-        self.map.fmt(formatter)
-    }
-}
-
 #[cfg(any(feature = "std", feature = "alloc"))]
 impl serde::ser::Serialize for Map<String, Value> {
     #[inline]