PMM-12899 add directory verification

build/local/update.sh

@@ -40,9 +40,40 @@ rewind() {
   fi
 }
 
+check-files() {
+  local DIR="$1"
+
+  test -z "DIR" && exit 1
+
+  if [ -d "$DIR/sources" ] && [ -f "$DIR/ci-default.yml" ] && [ -f "$DIR/ci.yml" ]; then
+    return 0
+  fi
+
+  return 1
+}
+
 main() {
+  local DEPS=
+  local CURDIR="$PWD"
+  local DIR=pmm-submodules
+
+  # Thouroughly verify the presence of known files, otherwise bail out
+  if check-files "."; then # pwd is pmm-submodules
+    DIR="."
+  elif [ -d "$DIR" ]; then # pwd is outside pmm-submodules
+    if ! check-files "$DIR"; then
+      echo "FATAL: could not locate known files in ${PWD}/${DIR}"
+      exit 1
+    fi
+  else
+    echo "FATAL: could not locate known files in $PWD"
+    exit 1
+  fi
+
+  cd "$DIR"
+
   # Join the dependencies from ci-default.yml and ci.yml
-  local DEPS=$(yq -o=json eval-all '. as $item ireduce ({}; . *d $item )' ci-default.yml ci.yml | jq '.deps')
+  DEPS=$(yq -o=json eval-all '. as $item ireduce ({}; . *d $item )' ci-default.yml ci.yml | jq '.deps')
 
   echo "This script rewinds submodule branches as per the joint config of 'ci-default.yml' and 'ci.yml'"
 
@@ -63,6 +94,8 @@ main() {
   echo
   echo "Printing git submodule status..."
   git submodule status
+
+  cd "$CURDIR" > /dev/null
 }
 
 main