From def2425406b4014b14b863e384d070ab6b58c24d Mon Sep 17 00:00:00 2001
From: Sergey Biryukov <sergeybiryukov@git.wordpress.org>
Date: Fri, 7 Aug 2020 14:27:40 +0000
Subject: [PATCH] Comments: Update comment cache in the upgrade routine for
 changing the `comment_type` DB field value in comments table.

This ensures that comment object cache is cleared after changing the comment type to `comment` instead of an empty string.

Add a unit test for `_wp_batch_update_comment_type()`.

Follow-up to [47597], [47626], [48225], [48227].

Props imath, westonruter.
Fixes #49236.

git-svn-id: https://develop.svn.wordpress.org/trunk@48748 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/comment.php                   | 23 +++++++--
 .../comment/wpBatchUpdateCommentType.php      | 49 +++++++++++++++++++
 2 files changed, 68 insertions(+), 4 deletions(-)
 create mode 100644 tests/phpunit/tests/comment/wpBatchUpdateCommentType.php

diff --git a/src/wp-includes/comment.php b/src/wp-includes/comment.php
index efcf384815..47e74bc3f2 100644
--- a/src/wp-includes/comment.php
+++ b/src/wp-includes/comment.php
@@ -3839,11 +3839,11 @@ function _wp_batch_update_comment_type() {
 	 */
 	$comment_batch_size = (int) apply_filters( 'wp_update_comment_type_batch_size', 100 );
 
-	// Update the `comment_type` field value to be `comment` for the next batch of comments.
-	$wpdb->query(
+	// Get the IDs of the comments to update.
+	$comment_ids = $wpdb->get_col(
 		$wpdb->prepare(
-			"UPDATE {$wpdb->comments}
-			SET comment_type = 'comment'
+			"SELECT comment_ID
+			FROM {$wpdb->comments}
 			WHERE comment_type = ''
 			ORDER BY comment_ID DESC
 			LIMIT %d",
@@ -3851,6 +3851,21 @@ function _wp_batch_update_comment_type() {
 		)
 	);
 
+	if ( $comment_ids ) {
+		$comment_id_list = implode( ',', $comment_ids );
+
+		// Update the `comment_type` field value to be `comment` for the next batch of comments.
+		$wpdb->query(
+			"UPDATE {$wpdb->comments}
+			SET comment_type = 'comment'
+			WHERE comment_type = ''
+			AND comment_ID IN ({$comment_id_list})" // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared
+		);
+
+		// Make sure to clean the comment cache.
+		clean_comment_cache( $comment_ids );
+	}
+
 	delete_option( $lock_name );
 }
 
diff --git a/tests/phpunit/tests/comment/wpBatchUpdateCommentType.php b/tests/phpunit/tests/comment/wpBatchUpdateCommentType.php
new file mode 100644
index 0000000000..ec7dec9ff3
--- /dev/null
+++ b/tests/phpunit/tests/comment/wpBatchUpdateCommentType.php
@@ -0,0 +1,49 @@
+<?php
+
+/**
+ * @group comment
+ * @covers ::_wp_batch_update_comment_type
+ */
+class Tests_Batch_Update_Comment_Type extends WP_UnitTestCase {
+
+	/**
+	 * @ticket 49236
+	 */
+	public function test__wp_batch_update_comment_type() {
+		global $wpdb;
+
+		$comment_ids     = self::factory()->comment->create_many( 3 );
+		$comment_id_list = implode( ',', $comment_ids );
+
+		$wpdb->query(
+			"UPDATE {$wpdb->comments}
+			SET comment_type = ''
+			WHERE comment_type = 'comment'
+			AND comment_ID in ({$comment_id_list})" // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared
+		);
+
+		clean_comment_cache( $comment_ids );
+
+		foreach ( $comment_ids as $comment_id ) {
+			$comment = get_comment( $comment_id );
+			$this->assertEmpty( $comment->comment_type );
+		}
+
+		add_filter( 'wp_update_comment_type_batch_size', array( $this, 'filter_comment_type_batch_size' ) );
+		add_filter( 'schedule_event', '__return_null' );
+
+		_wp_batch_update_comment_type();
+
+		remove_filter( 'wp_update_comment_type_batch_size', array( $this, 'filter_comment_type_batch_size' ) );
+		remove_filter( 'schedule_event', '__return_null' );
+
+		foreach ( $comment_ids as $comment_id ) {
+			$updated_comment = get_comment( $comment_id );
+			$this->assertEquals( 'comment', $updated_comment->comment_type );
+		}
+	}
+
+	public function filter_comment_type_batch_size() {
+		return 3;
+	}
+}