fixup! WIP: Rewrite to store loaders _and_ loaded configrethink

2 files changed, 42 insertions, 20 deletions

diff --git a/src/config/builder.rs b/src/config/builder.rs
index 9e3cce9..3748921 100644
--- a/src/config/builder.rs
+++ b/src/config/builder.rs
@@ -92,21 +92,32 @@ impl<'source> AsyncConfigBuilder<'source> {
         Config::build_from_async_builder(self).await
     }
 
-    pub(crate) async fn reload(&self) -> Result<Vec<ConfigObject<'source>>, SourceError> {
-        use futures::stream::FuturesOrdered;
-        use futures::stream::StreamExt;
-        use futures::FutureExt;
-        use itertools::Itertools;
+    pub(crate) async fn reload(&'source self) -> Result<Vec<ConfigObject<'source>>, SourceError> {
+        async fn do_load<'source>(builders: &'source Vec<Box<dyn AsyncConfigSource<'source>>>) -> Result<Vec<ConfigObject<'source>>, SourceError> {
+            let mut v = Vec::with_capacity(builders.len());
+            for cs in builders.iter() {
+                v.push(cs.load().await?);
+            }
+            Ok(v)
+        }
 
-        self.overwrites_builders
-            .iter()
-            .map(|cs| async move { cs.load().await }.boxed())
-            .chain(self.layers_builders.iter().map(|cs| async move { cs.load().await }.boxed()))
-            .chain(self.defaults_builders.iter().map(|cs| async move { cs.load().await }.boxed()))
-            .collect::<FuturesOrdered<_>>()
-            .collect::<Vec<Result<ConfigObject<'source>, SourceError>>>()
-            .await
-            .into_iter()
-            .collect()
+        let overwrites = do_load(&self.overwrites_builders);
+        let layers = do_load(&self.layers_builders);
+        let defaults = do_load(&self.defaults_builders);
+
+        let (mut overwrites, mut layers, mut defaults) =
+            futures::try_join!(overwrites, layers, defaults)?;
+
+        let mut v = Vec::with_capacity({
+            self.layers_builders.len()
+                + self.defaults_builders.len()
+                + self.overwrites_builders.len()
+        });
+
+        v.append(&mut overwrites);
+        v.append(&mut layers);
+        v.append(&mut defaults);
+
+        Ok(v)
     }
 }
diff --git a/src/config/config.rs b/src/config/config.rs
index 3442acb..568b3fa 100644
--- a/src/config/config.rs
+++ b/src/config/config.rs
@@ -36,6 +36,7 @@ impl<'source> Config<'source> {
 
         {
             let mut layers = config.layers.write().unwrap();
+            #[allow(irrefutable_let_patterns)]
             if let Builder::Sync(builder) = &config.builder {
                 *layers = Some(builder.reload()?);
             } else {
@@ -50,12 +51,22 @@ impl<'source> Config<'source> {
     pub(super) async fn build_from_async_builder(
         builder: AsyncConfigBuilder<'source>,
     ) -> Result<Config<'source>, ConfigError> {
-        let layers = builder.reload().await?;
-
-        Ok(Config {
-            layers: RwLock::new(Some(layers)),
+        let config = Config {
+            layers: RwLock::new(None),
             builder: Builder::Async(builder),
-        })
+        };
+
+        {
+            let l = match config.builder {
+                Builder::Sync(ref builder) => builder.reload()?,
+                Builder::Async(ref builder) => builder.reload().await?,
+            };
+
+            let mut layers = config.layers.write().unwrap();
+            *layers = Some(l);
+        }
+
+        Ok(config)
     }
 
     #[cfg(feature = "async")]