1#!/bin/bash
 2set -uo pipefail
 3
 4CHANGELOG_FILE="${1:-CHANGELOG.md}"
 5
 6if [ "${NO_CHANGELOG_LABEL}" = "true" ]; then
 7    # 'no changelog' set, so finish successfully
 8    echo "\"no changelog\" label has been set"
 9    exit 0
10else
11    # a changelog check is required
12    # fail if the diff is empty
13    if git diff --exit-code "origin/${BASE_REF}" -- "${CHANGELOG_FILE}"; then
14        >&2 echo "Changes should come with an entry in the \"CHANGELOG.md\" file. This behavior
15can be overridden by using the \"no changelog\" label, which is used for changes
16that are trivial / explicitly stated not to require a changelog entry."
17        exit 1
18    fi
19
20    echo "The \"CHANGELOG.md\" file has been updated."
21fi