Disallow C-style comments in migration files

.circleci/config.yml

@@ -41,6 +41,12 @@ jobs:
       - run:
           name: 'Check if changed'
           command: git diff --exit-code
+      - run:
+          name: 'Check for C-style comments in migration files'
+          command: ci/disallow_c_comments_in_migrations.sh
+      - run:
+          name: 'Check if changed'
+          command: git diff --exit-code
       - run:
           name: 'Check for banned C API usage'
           command: ci/banned.h.sh

ci/disallow_c_comments_in_migrations.sh

@@ -0,0 +1,26 @@
+#! /bin/bash
+
+set -euo pipefail
+
+# We do not use c-style comments in migration files as the stripped
+# zero-length migration files cause warning during packaging
+# See #3115 for more info
+
+# In this file, we aim to keep the indentation intact by capturing whitespaces,
+# and reusing them if needed. GNU sed unfortunately does not support lookaround assertions.
+
+# /* -> --
+find src/backend/distributed/sql/*.sql -print0 | xargs -0 sed -i 's#/\*#--#g'
+
+# */ -> `` (empty string)
+# remove all whitespaces immediately before the match
+find src/backend/distributed/sql/*.sql -print0 | xargs -0 sed -i 's#\s*\*/\s*##g'
+
+# * -> --
+# keep the indentation
+# allow only whitespaces before the match
+find src/backend/distributed/sql/*.sql -print0 | xargs -0 sed -i 's#^\(\s*\) \*#\1--#g'
+
+# // -> --
+# do not touch http:// or similar by allowing only whitespaces before //
+find src/backend/distributed/sql/*.sql -print0 | xargs -0 sed -i 's#^\(\s*\)//#\1--#g'

ci/fix_style.sh

@@ -10,5 +10,6 @@ cd ${cidir}/..
 
 ci/editorconfig.sh
 ci/remove_useless_declarations.sh
+ci/disallow_c_comments_in_migrations.sh
 
 citus_indent . --quiet

src/backend/distributed/sql/citus--9.2-2--9.2-4.sql

@@ -1,2 +1,2 @@
-/* we've some issues with versioning, and we're fixing it by bumping version */
+-- we've some issues with versioning, and we're fixing it by bumping version
-/* from 9.2-2 to 9.2-4 see #3673 for details */
+-- from 9.2-2 to 9.2-4 see #3673 for details

src/backend/distributed/sql/citus--9.2-4--9.3-2.sql

@@ -1,6 +1,6 @@
-/* citus--9.2-4--9.3-2 */
+-- citus--9.2-4--9.3-2
 
-/* bump version to 9.3-2 */
+-- bump version to 9.3-2
 
 #include "udfs/citus_extradata_container/9.3-2.sql"
 #include "udfs/update_distributed_table_colocation/9.3-2.sql"

src/backend/distributed/sql/citus--9.3-1--9.2-4.sql

@@ -1,10 +1,10 @@
-/* citus--9.3-1--9.2-4 */
+-- citus--9.3-1--9.2-4
-/* this is an unusual upgrade path, we are doing it because */
+-- this is an unusual upgrade path, we are doing it because
-/* we have accidentally tagged master branch with v9.2-3 */
+-- we have accidentally tagged master branch with v9.2-3
-/* however master branch was already bumped to v9.3-1 */
+-- however master branch was already bumped to v9.3-1
-/* with this file, we are undoing the catalog changes that */
+-- with this file, we are undoing the catalog changes that
-/* have happened between 9.2-2 to 9.3-1, and making 9.2-4 */
+-- have happened between 9.2-2 to 9.3-1, and making 9.2-4
-/* as the release that we can */
+-- as the release that we can
 
 -- undo the changes for citus_extradata_container that happened on citus 9.3
 DROP FUNCTION IF EXISTS pg_catalog.citus_extradata_container(INTERNAL);