From 0e9917f56198a25b603693c97f8694906d3378ad Mon Sep 17 00:00:00 2001
From: Jb Audras <audrasjb@git.wordpress.org>
Date: Mon, 8 Aug 2022 08:20:43 +0000
Subject: [PATCH] Editor: Safeguard `has_blocks()` against fatal errors.

This changeset ensures `has_blocks()` doesn't return a fatal error when `$post` is not a valid post. If the post can't be retrieved, the function now returns `false`.

Props Howdy_McGee, costdev, colonelphantom, audrasjb, dlh, peterwilsoncc.
Fixes #55705.


git-svn-id: https://develop.svn.wordpress.org/trunk@53858 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/blocks.php              |  7 +++++--
 tests/phpunit/tests/blocks/register.php | 15 +++++++++++++++
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/src/wp-includes/blocks.php b/src/wp-includes/blocks.php
index 62ba1843d7..f6c8f32706 100644
--- a/src/wp-includes/blocks.php
+++ b/src/wp-includes/blocks.php
@@ -425,9 +425,12 @@ function unregister_block_type( $name ) {
 function has_blocks( $post = null ) {
 	if ( ! is_string( $post ) ) {
 		$wp_post = get_post( $post );
-		if ( $wp_post instanceof WP_Post ) {
-			$post = $wp_post->post_content;
+
+		if ( ! $wp_post instanceof WP_Post ) {
+			return false;
 		}
+
+		$post = $wp_post->post_content;
 	}
 
 	return false !== strpos( (string) $post, '<!-- wp:' );
diff --git a/tests/phpunit/tests/blocks/register.php b/tests/phpunit/tests/blocks/register.php
index 6dcc0f8d04..1b40841b50 100644
--- a/tests/phpunit/tests/blocks/register.php
+++ b/tests/phpunit/tests/blocks/register.php
@@ -552,6 +552,21 @@ class Tests_Blocks_Register extends WP_UnitTestCase {
 		$this->assertFalse( has_blocks( $content ) );
 	}
 
+	/**
+	 * Tests that `has_blocks()` returns `false` with an invalid post.
+	 *
+	 * @ticket 55705
+	 *
+	 * @covers ::has_blocks
+	 */
+	public function test_has_blocks_with_invalid_post() {
+		$a_post = (object) array(
+			'ID'     => 55705,
+			'filter' => 'display',
+		);
+		$this->assertFalse( has_blocks( $a_post ) );
+	}
+
 	/**
 	 * @ticket 49615
 	 */