nix: Fix deployment parallelization

integration-tests/apply-fail/default.nix

@@ -0,0 +1,18 @@
+let
+  tools = import ../tools.nix {};
+in tools.makeTest {
+  name = "colmena-apply-fail";
+
+  bundle = ./.;
+
+  testScript = ''
+    beta.block()
+
+    # HACK: copy stderr to both stdout and stderr
+    # (stdout is what's returned, and only stderr appears on screen during the build)
+    logs = deployer.fail("cd /tmp/bundle && ${tools.colmenaExec} apply -v --eval-node-limit 4 --on @target 2> >(tee /dev/stderr)")
+
+    alpha.succeed("grep SUCCESS /etc/deployment")
+    gamma.succeed("grep SUCCESS /etc/deployment")
+  '';
+}

integration-tests/apply-fail/hive.nix

@@ -0,0 +1,23 @@
+let
+  tools = import ./tools.nix { insideVm = true; };
+
+  testPkg = let
+    text = builtins.trace "must appear during evaluation" ''
+      echo "must appear during build"
+      mkdir -p $out
+    '';
+  in tools.pkgs.runCommand "test-package" {} text;
+in {
+  meta = {
+    nixpkgs = tools.pkgs;
+  };
+
+  defaults = {
+    environment.etc."deployment".text = "SUCCESS";
+  };
+
+  deployer = tools.getStandaloneConfigFor "deployer";
+  alpha = tools.getStandaloneConfigFor "alpha";
+  beta = tools.getStandaloneConfigFor "beta";
+  gamma = tools.getStandaloneConfigFor "gamma";
+}

integration-tests/default.nix

@@ -1,5 +1,6 @@
 {
   apply = import ./apply;
+  apply-fail = import ./apply-fail;
   apply-local = import ./apply-local;
   exec = import ./exec;
 }

src/nix/deployment/mod.rs

@@ -226,11 +226,16 @@ impl Deployment {
             return Ok(());
         }
 
+        let mut futures = Vec::new();
+
         for (name, profile) in profiles.iter() {
             let target = chunk.remove(name).unwrap();
-            self.clone().deploy_node(parent.clone(), target, profile.clone()).await?;
+            futures.push(self.clone().deploy_node(parent.clone(), target, profile.clone()));
         }
 
+        let result: NixResult<Vec<()>> = join_all(futures).await.into_iter().collect();
+        result?;
+
         // Create GC root
         if self.options.create_gc_roots {
             let job = parent.create_job(JobType::CreateGcRoots, nodes.clone())?;