hydra-eval-jobset: write a test validating the events that comes out

t/jobs/hydra-eval-notifications.nix

@@ -0,0 +1,30 @@
+# This file gets copied around, and intentionally does not refer to
+# anything but itself as "default.nix".
+
+let
+  simpleDerivation = name: builderText: derivation {
+    inherit name;
+    system = builtins.currentSystem;
+    builder = "/bin/sh";
+    args = [
+      (builtins.toFile "builder.sh" builderText)
+    ];
+  };
+in
+{
+  stable-job-queued = simpleDerivation "stable-job-queued" ''
+    echo "here is a stable job that passes every time" > $out
+  '';
+
+  stable-job-passing = simpleDerivation "stable-job-passing" ''
+    echo "here is a stable job that passes every time" > $out
+  '';
+
+  stable-job-failing = simpleDerivation "stable-job-failing" ''
+    echo "this job is a stable job that fails every time" > $out
+  '';
+
+  variable-job = simpleDerivation "variable-job" ''
+    echo ${builtins.toFile "default.nix" (builtins.readFile ./default.nix)} > $out
+  '';
+}