From d433884a1dcef19e795b36aafba7c65e7d3bf94c Mon Sep 17 00:00:00 2001
From: Kyle Morgan <kyle.morgan@block.one>
Date: Wed, 3 Apr 2019 13:09:44 -0400
Subject: [PATCH] Add git submodule regression check

* Add submodule_check.sh, which checks to see if the HEAD of any
  submodules on a pull-requested branch are older than they were
  previously.
* Add the corresponding buildkite pipeline to run submodule_check.sh.
---
 .buildkite/pipeline.yml    |  8 ++++++++
 scripts/submodule_check.sh | 35 +++++++++++++++++++++++++++++++++++
 2 files changed, 43 insertions(+)
 create mode 100755 scripts/submodule_check.sh

diff --git a/.buildkite/pipeline.yml b/.buildkite/pipeline.yml
index f83249df044..c1500cd77ee 100644
--- a/.buildkite/pipeline.yml
+++ b/.buildkite/pipeline.yml
@@ -614,3 +614,11 @@ steps:
       - "build/packages/eosio_highsierra.rb"
       - "build/packages/eosio.rb"
     timeout: 60
+
+  - command: |
+        echo "+++ :microscope: Running git submodule regression check" && \
+        ./scripts/submodule_check.sh
+    label: "Git submodule regression check"
+    agents:
+      queue: "automation-large-builder-fleet"
+    timeout: 240
diff --git a/scripts/submodule_check.sh b/scripts/submodule_check.sh
new file mode 100755
index 00000000000..16aace418bf
--- /dev/null
+++ b/scripts/submodule_check.sh
@@ -0,0 +1,35 @@
+#!/bin/bash
+
+REPO_DIR=`mktemp -d`
+git clone "$BUILDKITE_REPO" "$REPO_DIR"
+git submodule update --init --recursive
+cd "$REPO_DIR"
+
+declare -A PR_MAP
+declare -A BASE_MAP
+
+echo "getting submodule info for $BUILDKITE_BRANCH"
+git checkout "$BUILDKITE_BRANCH" &> /dev/null
+git submodule update --init &> /dev/null
+while read -r a b; do
+  PR_MAP[$a]=$b
+done < <(git submodule --quiet foreach --recursive 'echo $path `git log -1 --format=%ct`')
+
+echo "getting submodule info for $BUILDKITE_PULL_REQUEST_BASE_BRANCH"
+git checkout "$BUILDKITE_PULL_REQUEST_BASE_BRANCH" &> /dev/null
+git submodule update --init &> /dev/null
+while read -r a b; do
+  BASE_MAP[$a]=$b
+done < <(git submodule --quiet foreach --recursive 'echo $path `git log -1 --format=%ct`')
+
+for k in "${!BASE_MAP[@]}"; do
+  base_ts=${BASE_MAP[$k]}
+  pr_ts=${PR_MAP[$k]}
+  echo "submodule $k"
+  echo "  timestamp on $BUILDKITE_BRANCH: $pr_ts"
+  echo "  timestamp on $BUILDKITE_PULL_REQUEST_BASE_BRANCH: $base_ts"
+  if (( $pr_ts < $base_ts)); then
+    echo "ERROR: $k is older on $BUILDKITE_BRANCH than $BUILDKITE_PULL_REQUEST_BASE_BRANCH"
+    exit 1
+  fi
+done