Send a message on GitHub when a duplicate preflight poll terminates.

lib/worker/batcher.ex

@@ -249,13 +249,15 @@ defmodule BorsNG.Worker.Batcher do
 
     Logger.info("Continue Poll Patch #{patch.id} prerun")
 
+    project = Repo.get(Project, patch.project_id)
+    repo_conn = get_repo_conn(project)
+
     case Repo.get(Patch.all(:awaiting_review), patch.id) do
       nil ->
+        send_message(repo_conn, [patch], {:preflight, :duplicate})
         Logger.info("Patch #{patch.id} already left prerun, exiting prerun poll loop")
 
       _ ->
-        project = Repo.get(Project, patch.project_id)
-        repo_conn = get_repo_conn(project)
         {:ok, toml} = Batcher.GetBorsToml.get(repo_conn, patch.commit)
 
         prerun_timeout_ms = toml.prerun_timeout_sec * 1000

lib/worker/batcher/message.ex

@@ -43,6 +43,10 @@ defmodule BorsNG.Worker.Batcher.Message do
     "All preflight checks passed. Batching this PR into the staging branch."
   end
 
+  def generate_message({:preflight, :duplicate}) do
+    "Stopped waiting for PR status (Github check) without running due to duplicate requests to run. You may check Bors to see that this PR is included in a batch by one of the other requests."
+  end
+
   def generate_message({:preflight, :timeout}) do
     "GitHub status checks took too long to complete, so bors is giving up. You can adjust bors configuration to have it wait longer if you like."
   end

test/batcher/batcher_test.exs

@@ -1160,6 +1160,8 @@ defmodule BorsNG.Worker.BatcherTest do
                commits: %{},
                comments: %{
                  1 => [
+                   "Stopped waiting for PR status (Github check) without running due to duplicate requests to run. You may check Bors to see that this PR is included in a batch by one of the other requests.",
+                   "Stopped waiting for PR status (Github check) without running due to duplicate requests to run. You may check Bors to see that this PR is included in a batch by one of the other requests.",
                    ":clock1: Waiting for PR status (Github check) to be set, probably by CI. Bors will automatically try to run when all required PR statuses are set."
                  ]
                },