Merge pull request #233 from michael-p/schema-for-cow

Implement `Schema` for `Cow`

Author: jamesmunns

source/postcard-schema/src/impls/builtins_alloc.rs

@@ -4,25 +4,35 @@ use crate::{schema::DataModelType, Schema};
 
 extern crate alloc;
 
+#[cfg_attr(docsrs, doc(cfg(any(feature = "alloc", feature = "use-std"))))]
 impl<T: Schema> Schema for alloc::vec::Vec<T> {
     const SCHEMA: &'static DataModelType = &DataModelType::Seq(T::SCHEMA);
 }
 
+#[cfg_attr(docsrs, doc(cfg(any(feature = "alloc", feature = "use-std"))))]
 impl Schema for alloc::string::String {
     const SCHEMA: &'static DataModelType = &DataModelType::String;
 }
 
+#[cfg_attr(docsrs, doc(cfg(any(feature = "alloc", feature = "use-std"))))]
 impl<K: Schema, V: Schema> Schema for alloc::collections::BTreeMap<K, V> {
     const SCHEMA: &'static DataModelType = &DataModelType::Map {
         key: K::SCHEMA,
         val: V::SCHEMA,
     };
 }
 
+#[cfg_attr(docsrs, doc(cfg(any(feature = "alloc", feature = "use-std"))))]
 impl<K: Schema> Schema for alloc::collections::BTreeSet<K> {
     const SCHEMA: &'static DataModelType = &DataModelType::Seq(K::SCHEMA);
 }
 
+#[cfg_attr(docsrs, doc(cfg(any(feature = "alloc", feature = "use-std"))))]
 impl<T: Schema> Schema for alloc::boxed::Box<T> {
     const SCHEMA: &'static DataModelType = T::SCHEMA;
 }
+
+#[cfg_attr(docsrs, doc(cfg(any(feature = "alloc", feature = "use-std"))))]
+impl<T: ?Sized + Schema + alloc::borrow::ToOwned> Schema for alloc::borrow::Cow<'_, T> {
+    const SCHEMA: &'static DataModelType = T::SCHEMA;
+}

source/postcard-schema/src/impls/builtins_std.rs

@@ -47,3 +47,8 @@ impl<K: Schema> Schema for std::collections::BTreeSet<K> {
 impl<T: Schema> Schema for std::boxed::Box<T> {
     const SCHEMA: &'static DataModelType = T::SCHEMA;
 }
+
+#[cfg_attr(docsrs, doc(cfg(any(feature = "alloc", feature = "use-std"))))]
+impl<T: ?Sized + Schema + std::borrow::ToOwned> Schema for std::borrow::Cow<'_, T> {
+    const SCHEMA: &'static DataModelType = T::SCHEMA;
+}