Check newsfile more carefully (correct number, correct punctuation)

scripts-dev/check_newsfragment.sh

@@ -0,0 +1,45 @@
+#!/usr/bin/env bash
+#
+# A script which checks that an appropriate news file has been added on this
+# branch.
+
+echo -e "+++ \033[32mChecking newsfragment\033[m"
+
+set -e
+
+# make sure that origin/develop is up to date
+# XXX TODO git remote set-branches --add origin develop
+# XXX TODO git fetch -q origin develop
+
+pr="$1"
+
+# Print a link to the contributing guide if the user makes a mistake
+CONTRIBUTING_GUIDE_TEXT="!! Please see the contributing guide for help writing your changelog entry:
+https://github.com/matrix-org/synapse/blob/develop/CONTRIBUTING.md#changelog"
+
+# If towncrier returns a non-zero exit code, print the contributing guide and exit
+python -m towncrier.check --compare-with="origin/main" || (echo -e "$CONTRIBUTING_GUIDE_TEXT" >&2 && exit 1)
+
+echo
+echo "--------------------------"
+echo
+
+matched=0
+for f in `git diff --name-only FETCH_HEAD... -- changelog.d`; do
+    # check that any modified newsfiles on this branch end with a full stop.
+    lastchar=`tr -d '\n' < $f | tail -c 1`
+    if [ $lastchar != '.' -a $lastchar != '!' ]; then
+        echo -e "\e[31mERROR: newsfragment $f does not end with a '.' or '!'\e[39m" >&2
+        echo -e "$CONTRIBUTING_GUIDE_TEXT" >&2
+        exit 1
+    fi
+
+    # see if this newsfile corresponds to the right PR
+    [[ -n "$pr" && "$f" == changelog.d/"$pr".* ]] && matched=1
+done
+
+if [[ -n "$pr" && "$matched" -eq 0 ]]; then
+    echo -e "\e[31mERROR: Did not find a news fragment with the right number: expected changelog.d/$pr.*.\e[39m" >&2
+    echo -e "$CONTRIBUTING_GUIDE_TEXT" >&2
+    exit 1
+fi