Script to find duplicate usernames only differing in case

Usage:
    cd /path/to/All-Users.git
    find-duplicate-usernames.sh [username|gerrit]

This script finds duplicate usernames only differing in case in the
given account schema ("username" or "gerrit") and their respective
accountIds.

Change-Id: I16713471ef026736274695f815428bf68c768e0c

1 files changed, 49 insertions, 0 deletions

diff --git a/contrib/find-duplicate-usernames.sh b/contrib/find-duplicate-usernames.sh
new file mode 100755
index 0000000000..f9bcf8810e
--- /dev/null
+++ b/contrib/find-duplicate-usernames.sh
@@ -0,0 +1,49 @@
+#!/bin/bash
+# Copyright (C) 2021 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+usage() {
+  f="$(basename -- $0)"
+  cat <<EOF
+Usage:
+    cd /path/to/All-Users.git
+    "$f [username|gerrit]"
+
+This script finds duplicate usernames only differing in case in the given
+account schema ("username" or "gerrit") and their respective accountIds.
+EOF
+  exit 1
+}
+
+if [[ "$#" -ne "1" ]] || ! [[ "$1" =~ ^(gerrit|username)$ ]]; then
+  usage
+fi
+
+# find lines with user name and subsequent line in external-ids notes branch
+# remove group separators
+# remove line break between user name and accountId lines
+# unify separators to ":"
+# cut on ":", select username and accountId fields
+# sort case-insensitive
+# flip columns
+# uniq case-insensitive, only show duplicates, avoid comparing first field
+# flip columns back
+git grep -A1 "\[externalId \"$1:" refs/meta/external-ids \
+  | sed -E "/$1/,/accountId/!d" \
+  | paste -d ' ' - - \
+  | tr \"= : \
+  | cut -d: --output-delimiter="" -f 5,8 \
+  | sort -f \
+  | sed -E "s/(.*) (.*)/\2 \1/" \
+  | uniq -Di -f1 \
+  | sed -E "s/(.*) (.*)/\2 \1/"