Refactor: Chain iterators and collect at once

This improves the collection building be reducing the asyncness.
The stream is build first and then all futures are collected. Before
this patch, two streams were collected and then appended.

Not sure whether this improves runtime, but it certainly improves
readability.

Unfortunately, collecting the additional job resources right into the
streams is not that easy and thus the resulting collection is simply
extend()ed.

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

1 files changed, 19 insertions, 15 deletions

diff --git a/src/job/runnable.rs b/src/job/runnable.rs
index 215fcbc..4a9180f 100644
--- a/src/job/runnable.rs
+++ b/src/job/runnable.rs
@@ -58,27 +58,31 @@ impl RunnableJob {
     pub async fn build_from_job(job: Job, merged_stores: &MergedStores, source_cache: &SourceCache, config: &Configuration) -> Result<Self> {
         trace!("Preparing build dependencies");
         let resources = {
-            let deps = job.package().dependencies();
-            let build = deps
+            let mut resources = job
+                .package()
+                .dependencies()
                 .build()
                 .into_iter()
                 .map(|dep| Self::build_resource(dep, merged_stores))
+                .chain({
+                    job.package()
+                        .dependencies()
+                        .runtime()
+                        .into_iter()
+                        .map(|dep| Self::build_resource(dep, merged_stores))
+                })
                 .collect::<futures::stream::FuturesUnordered<_>>()
-                .collect::<Result<Vec<JobResource>>>();
-
-            let rt = deps
-                .runtime()
-                .into_iter()
-                .map(|dep| Self::build_resource(dep, merged_stores))
-                .collect::<futures::stream::FuturesUnordered<_>>()
-                .collect::<Result<Vec<JobResource>>>();
+                .collect::<Result<Vec<JobResource>>>()
+                .await?;
 
-            let (build, rt)         = tokio::join!(build, rt);
-            let (mut build, mut rt) = (build?, rt?);
+            resources.extend({
+                job.resources()
+                    .iter()
+                    .filter(|jr| jr.env().is_some())
+                    .cloned()
+            });
 
-            build.append(&mut rt);
-            build.extend(job.resources().iter().filter(|jr| jr.env().is_some()).cloned());
-            build
+            resources
         };
 
         if config.containers().check_env_names() {