ci/github-script/bot: move getTeamMembers cache into main file

This allows re-using this elsewhere with a shared cache.

ci/github-script/bot.js

@@ -96,6 +96,29 @@ module.exports = async ({ github, context, core, dry }) => {
     return maintainerMaps[branch]
   }
 
+  // Caching the list of team members saves API requests when running the bot on the schedule and
+  // processing many PRs at once.
+  const members = {}
+  function getTeamMembers(team_slug) {
+    if (context.eventName === 'pull_request') {
+      // We have no chance of getting a token in the pull_request context with the right
+      // permissions to access the members endpoint below. Thus, we're pretending to have
+      // no members. This is OK; because this is only for the Test workflow, not for
+      // real use.
+      return []
+    }
+
+    if (!members[team_slug]) {
+      members[team_slug] = github.paginate(github.rest.teams.listMembersInOrg, {
+        org: context.repo.owner,
+        team_slug,
+        per_page: 100,
+      })
+    }
+
+    return members[team_slug]
+  }
+
   async function handlePullRequest({ item, stats, events }) {
     const log = (k, v) => core.info(`PR #${item.number} - ${k}: ${v}`)
 
@@ -121,6 +144,7 @@ module.exports = async ({ github, context, core, dry }) => {
       pull_request,
       events,
       maintainers,
+      getTeamMembers,
     })
 
     // When the same change has already been merged to the target branch, a PR will still be

ci/github-script/merge.js

@@ -109,10 +109,6 @@ async function handleMergeComment({ github, body, node_id, reaction }) {
   )
 }
 
-// Caching the list of team members saves API requests when running the bot on the schedule and
-// processing many PRs at once.
-const members = {}
-
 async function handleMerge({
   github,
   context,
@@ -122,31 +118,13 @@ async function handleMerge({
   pull_request,
   events,
   maintainers,
+  getTeamMembers,
 }) {
   const pull_number = pull_request.number
 
-  function getTeamMembers(team_slug) {
+  const committers = new Set(
-    if (context.eventName === 'pull_request') {
+    (await getTeamMembers('nixpkgs-committers')).map(({ id }) => id),
-      // We have no chance of getting a token in the pull_request context with the right
+  )
-      // permissions to access the members endpoint below. Thus, we're pretending to have
-      // no members. This is OK; because this is only for the Test workflow, not for
-      // real use.
-      return new Set()
-    }
-
-    if (!members[team_slug]) {
-      members[team_slug] = github
-        .paginate(github.rest.teams.listMembersInOrg, {
-          org: context.repo.owner,
-          team_slug,
-          per_page: 100,
-        })
-        .then((members) => new Set(members.map(({ id }) => id)))
-    }
-
-    return members[team_slug]
-  }
-  const committers = await getTeamMembers('nixpkgs-committers')
 
   const files = await github.paginate(github.rest.pulls.listFiles, {
     ...context.repo,