From ba7d3a52b16bec0baed2c1f36b88da1cf0b472cc Mon Sep 17 00:00:00 2001
From: Tonya Mork <hellofromtonya@git.wordpress.org>
Date: Tue, 4 Jan 2022 18:38:52 +0000
Subject: [PATCH] Themes: Make block themes support HTML5 by default.

For block themes, [52369] added HTML5 support for `'comment-list'`, `'comment-form'`, `'style'`, and `'script'`. However, when sites upgrade to 5.9 with non-block content such as a gallery and caption, the markup was not HTML5.

This commit adds full HTML5 theme feature support for block themes. Non-block content such as a `[gallery]` and `[caption]` shortcodes will natively be in HMTL5 markup without block themes needing to specifically add `add_theme_support( 'html5, .. )` to the theme.

Follow-up to [24417], [27302], [34261], [52369], [52383], [52386].

Props @joyously, costdev, hellofromTonya, audrasjb, Mamaduka, ocean90.
Fixes #54731. See #54597.

git-svn-id: https://develop.svn.wordpress.org/trunk@52439 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/theme.php     |  7 ++++++-
 tests/phpunit/tests/theme.php | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/src/wp-includes/theme.php b/src/wp-includes/theme.php
index ed33051c08..7a2b357d0a 100644
--- a/src/wp-includes/theme.php
+++ b/src/wp-includes/theme.php
@@ -4181,7 +4181,12 @@ function _add_default_theme_supports() {
 	add_theme_support( 'post-thumbnails' );
 	add_theme_support( 'responsive-embeds' );
 	add_theme_support( 'editor-styles' );
-	add_theme_support( 'html5', array( 'comment-form', 'comment-list', 'style', 'script' ) );
+	/*
+	 * Makes block themes support HTML5 by default for the comment block and search form
+	 * (which use default template functions) and `[caption]` and `[gallery]` shortcodes. 
+	 * Other blocks contain their own HTML5 markup.
+	 */
+	add_theme_support( 'html5', array( 'comment-form', 'comment-list', 'search-form', 'gallery', 'caption', 'style', 'script' ) );
 	add_theme_support( 'automatic-feed-links' );
 
 	add_filter( 'should_load_separate_core_block_assets', '__return_true' );
diff --git a/tests/phpunit/tests/theme.php b/tests/phpunit/tests/theme.php
index 23e2efad73..e16dd4c900 100644
--- a/tests/phpunit/tests/theme.php
+++ b/tests/phpunit/tests/theme.php
@@ -706,6 +706,8 @@ class Tests_Theme extends WP_UnitTestCase {
 	 * Tests that block themes support a feature by default.
 	 *
 	 * @ticket 54597
+	 * @ticket 54731
+	 *
 	 * @dataProvider data_block_theme_has_default_support
 	 *
 	 * @covers ::_add_default_theme_supports
@@ -763,6 +765,36 @@ class Tests_Theme extends WP_UnitTestCase {
 					'feature' => 'editor-styles',
 				),
 			),
+			'html5: comment-list'  => array(
+				'support' => array(
+					'feature'     => 'html5',
+					'sub_feature' => 'comment-list',
+				),
+			),
+			'html5: comment-form'  => array(
+				'support' => array(
+					'feature'     => 'html5',
+					'sub_feature' => 'comment-form',
+				),
+			),
+			'html5: search-form'   => array(
+				'support' => array(
+					'feature'     => 'html5',
+					'sub_feature' => 'search-form',
+				),
+			),
+			'html5: gallery'       => array(
+				'support' => array(
+					'feature'     => 'html5',
+					'sub_feature' => 'gallery',
+				),
+			),
+			'html5: caption'       => array(
+				'support' => array(
+					'feature'     => 'html5',
+					'sub_feature' => 'caption',
+				),
+			),
 			'html5: style'         => array(
 				'support' => array(
 					'feature'     => 'html5',