Make Backend need Copy, so we can pass it around

Signed-off-by: Matthias Beyer <mail@beyermatthias.de>

5 files changed, 14 insertions, 11 deletions

diff --git a/src/backend/dialoguer.rs b/src/backend/dialoguer.rs
index 6b08507..564750f 100644
--- a/src/backend/dialoguer.rs
+++ b/src/backend/dialoguer.rs
@@ -5,6 +5,7 @@ use crate::BuildableCollection;
 use crate::CollectionBuilder;
 use crate::ValueBuilder;
 
+#[derive(Copy, Clone)]
 pub struct DialoguerBackend;
 
 impl Backend for DialoguerBackend {
diff --git a/src/backend/mod.rs b/src/backend/mod.rs
index bd5bc58..757703c 100644
--- a/src/backend/mod.rs
+++ b/src/backend/mod.rs
@@ -6,7 +6,7 @@ use crate::CollectionBuilder;
 use crate::ValueBuilder;
 
 /// A backend can be used to get builders for specific types
-pub trait Backend {
+pub trait Backend: Copy {
     fn bool_builder(&self)   -> Box<dyn ValueBuilder<Output = bool>>;
     fn u8_builder(&self)     -> Box<dyn ValueBuilder<Output = u8>>;
     fn u16_builder(&self)    -> Box<dyn ValueBuilder<Output = u16>>;
diff --git a/src/buildable.rs b/src/buildable.rs
index 54e7bbe..0436456 100644
--- a/src/buildable.rs
+++ b/src/buildable.rs
@@ -147,14 +147,14 @@ impl BuildableValue for String {
 
 pub trait BuildableCollection {
     fn builder<B>(backend: B) -> Box<dyn CollectionBuilder<Output = Self>>
-        where B: Backend;
+        where B: 'static + Backend;
 }
 
 impl<T> BuildableCollection for Vec<T>
     where T: 'static + BuildableValue,
 {
     fn builder<B>(backend: B) -> Box<dyn CollectionBuilder<Output = Self>>
-        where B: Backend
+        where B: 'static + Backend
     {
         backend.vec_builder::<T>()
     }
@@ -164,7 +164,7 @@ impl<T> BuildableCollection for Option<T>
     where T: 'static + BuildableValue + Sized,
 {
     fn builder<B>(backend: B) -> Box<dyn CollectionBuilder<Output = Option<T>>>
-        where B: Backend
+        where B: 'static + Backend
     {
         backend.option_builder()
     }
diff --git a/tests/common/mod.rs b/tests/common/mod.rs
index 26e0066..0ab668a 100644
--- a/tests/common/mod.rs
+++ b/tests/common/mod.rs
@@ -1,6 +1,8 @@
 use interactive_object_builder::*;
 
+#[derive(Copy, Clone)]
 pub struct DummyBackend;
+
 impl Backend for DummyBackend {
     fn bool_builder(&self) -> Box<dyn ValueBuilder<Output = bool>> {
         Box::new(BoolValBuilder)
diff --git a/tests/struct.rs b/tests/struct.rs
index 415c2dc..9845278 100644
--- a/tests/struct.rs
+++ b/tests/struct.rs
@@ -9,22 +9,22 @@ pub struct Configuration {
 }
 
 impl BuildableCollection for Configuration {
-    fn builder<B>(_backend: B) -> Box<dyn CollectionBuilder<Output = Self>>
-        where B: Backend
+    fn builder<B>(backend: B) -> Box<dyn CollectionBuilder<Output = Self>>
+        where B: 'static + Backend
     {
-        Box::new(ConfigStructBuilder)
+        Box::new(ConfigStructBuilder(backend.clone()))
     }
 }
 
-pub struct ConfigStructBuilder;
-impl CollectionBuilder for ConfigStructBuilder {
+pub struct ConfigStructBuilder<B: Backend>(B);
+impl<B: 'static + Backend> CollectionBuilder for ConfigStructBuilder<B> {
     type Output = Configuration;
 
     fn build_collection(&self, value_desc: &str) -> Result<Self::Output> {
         println!("Building {}", value_desc);
 
-        let verbose = bool::builder(DummyBackend).build_value(value_desc)?;
-        let values = Vec::<u8>::builder(DummyBackend).build_collection(value_desc)?;
+        let verbose = bool::builder(self.0).build_value(value_desc)?;
+        let values = Vec::<u8>::builder(self.0).build_collection(value_desc)?;
 
         Ok(Configuration {
             verbose,