test release rotation: factor out selection (#11161)

CHANGELOG_BEGIN
CHANGELOG_END

azure-pipelines.yml

@@ -131,10 +131,11 @@ jobs:
       condition: and(succeeded(), not(eq(variables['skip-github'], 'TRUE')))
     - bash: |
         set -euo pipefail
+        source $(bash-lib)
         msg=$(git log -n1 --format=%b HEAD | head -1)
         # Keep this line in sync with RELEASE_PR_NOTIF in ci/cron/wednesday.yml
         if [ "$msg" = "This PR has been created by a script, which is not very smart" ]; then
-            pr_handler="<@$(awk '/^[^#]/ {print $1}' release/rotation | head -n 1)>"
+            pr_handler="<@$(next_in_rotation_slack)>"
         else
             pr_handler=""
         fi

ci/bash-lib.yml

@@ -8,6 +8,7 @@ steps:
 - bash: |
     set -euo pipefail
     TMP=$(mktemp)
+    PROJ_DIR="$(pwd)"
     cat > $TMP <<'END'
     escape_slack() {
       local r
@@ -148,6 +149,15 @@ steps:
       echo "Setting '$1' to '$2'"
       echo "##vso[task.setvariable variable=$1;isOutput=true]$2"
     }
+    next_in_rotation() {
+      awk '/^[^#]/ {print $0}' "$PROJ_DIR/release/rotation" | head -n 1
+    }
+    next_in_rotation_slack() {
+      next_in_rotation | awk '{print $1}'
+    }
+    next_in_rotation_github() {
+      next_in_rotation | awk '{print $2}'
+    }
 
     END
     echo "##vso[task.setvariable variable=${{parameters.var_name}}]$TMP"

ci/cron/tuesday.yml

@@ -28,6 +28,6 @@ jobs:
 
       source "$(bash_lib)"
 
-      RELEASE_MANAGER=$(awk '/^[^#]/ {print $1}' release/rotation | head -n 1)
+      RELEASE_MANAGER=$(next_in_rotation_slack)
 
       tell_slack "$(echo -e "Hi <@$RELEASE_MANAGER>! According to the <https://github.com/digital-asset/daml/blob/main/release/rotation|rotation>, you are in charge of the release tomorrow. Please make sure you plan accordingly, or find a replacement.\n\nIf anyone knows of any reason to delay or block the release (e.g. a PR that needs to get merged first), please make it known in thread before EOD.")"

ci/cron/wednesday.yml

@@ -88,14 +88,12 @@ jobs:
           # labels, PRs are issues as far as the GH API is concerned.
       }
       rotate() {
-          # limitation: comments in the middle of the rotation will be hoisted to the top
-          local comments rotation
-          comments=$(mktemp)
-          rotation=$(mktemp)
-          awk '/^#/' release/rotation > $comments
-          awk '/^[^#]/' release/rotation > $rotation
-          cp $comments release/rotation
-          (tail -n +2 $rotation; head -1 $rotation) >> release/rotation
+          local tmp next
+          tmp=$(mktemp)
+          next=$(next_in_rotation)
+          grep -v "$next" release/rotation > $tmp
+          echo "$next" >> $tmp
+          mv $tmp release/rotation
       }
       release_message() {
           local handler=$1
@@ -123,8 +121,8 @@ jobs:
 
       reset
 
-      NEXT_SLACK=$(awk '/^[^#]/ {print $1}' release/rotation | head -n 1)
-      NEXT_GH=$(awk '/^[^#]/ {print $2}' release/rotation | head -n 1)
+      NEXT_SLACK=$(next_in_rotation_slack)
+      NEXT_GH=$(next_in_rotation_github)
 
       PREV="v$(head -1 LATEST | awk '{print $2}')"
       ./release.sh new snapshot

ci/prs.yml

@@ -123,7 +123,7 @@ jobs:
         # API, there is still value in getting the notification on Slack, as
         # we do have the build number and from there we can click through to
         # the PR. Hence the `|| echo ""`.
-        PR_HANDLER=$(awk '/^[^#]/ {print $1}' release/rotation | head -n 1)
+        PR_HANDLER=$(next_in_rotation_slack)
 
         case "$(status)" in
           Succeeded*)