From 752ce7db9e8aff33c578c931e2c462fa59bbef4e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andr=C3=A9?= <583546+oandregal@users.noreply.github.com>
Date: Tue, 13 Dec 2022 16:14:23 +0100
Subject: [PATCH 01/15] Add new public method wp_theme_has_theme_json

---
 .../global-styles-and-settings.php            | 40 +++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/src/wp-includes/global-styles-and-settings.php b/src/wp-includes/global-styles-and-settings.php
index b6c8c91b464c0..96fac51ce9e61 100644
--- a/src/wp-includes/global-styles-and-settings.php
+++ b/src/wp-includes/global-styles-and-settings.php
@@ -255,3 +255,43 @@ function ( $item ) {
 		}
 	}
 }
+
+/**
+ * Whether a theme or its parent have a theme.json file.
+ *
+ * @since 6.2.0
+ *
+ * @return boolean
+ */
+function wp_theme_has_theme_json() {
+	$cache_group       = 'theme_json';
+	$cache_key         = 'wp_theme_has_theme_json';
+	$theme_has_support = wp_cache_get( $cache_key, $cache_group );
+
+	/**
+	 * $theme_has_support is stored as an int in the cache.
+	 *
+	 * The reason not to store it as a boolean is to avoid working
+	 * with the $found parameter which apparently had some issues in some implementations
+	 * https://developer.wordpress.org/reference/functions/wp_cache_get/
+	 *
+	 * Ignore cache when `WP_DEBUG` is enabled, so it doesn't interfere with the theme developers workflow.
+	 */
+	if ( ! WP_DEBUG && is_int( $theme_has_support ) ) {
+		return (bool) $theme_has_support;
+	}
+
+	// Has the own theme a theme.json?
+	$theme_has_support = is_readable( get_stylesheet_directory() . '/theme.json' );
+
+	// Look up the parent if the child does not have a theme.json.
+	if ( ! $theme_has_support ) {
+		$theme_has_support = is_readable( get_template_directory() . '/theme.json' );
+	}
+
+	$theme_has_support = $theme_has_support ? 1 : 0;
+
+	wp_cache_set( $cache_key, $theme_has_support, $cache_group );
+
+	return (bool) $theme_has_support;
+}

From bb9d154eb08dbc3fad2ab4852a18af9e1a45940d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andr=C3=A9?= <583546+oandregal@users.noreply.github.com>
Date: Tue, 13 Dec 2022 16:18:51 +0100
Subject: [PATCH 02/15] Substitute WP_Theme_JSON_Resolver::theme_has_support by
 wp_theme_has_theme_json

---
 src/wp-admin/edit-form-blocks.php             |  2 +-
 src/wp-admin/site-editor.php                  |  2 +-
 src/wp-includes/block-editor.php              |  2 +-
 src/wp-includes/block-patterns.php            |  2 +-
 src/wp-includes/block-supports/layout.php     |  4 +--
 src/wp-includes/block-template-utils.php      |  4 +--
 .../class-wp-theme-json-resolver.php          | 25 +++++--------------
 .../global-styles-and-settings.php            |  4 +--
 src/wp-includes/script-loader.php             |  6 ++---
 src/wp-includes/theme-templates.php           |  2 +-
 .../tests/theme/wpThemeJsonResolver.php       |  2 +-
 11 files changed, 21 insertions(+), 34 deletions(-)

diff --git a/src/wp-admin/edit-form-blocks.php b/src/wp-admin/edit-form-blocks.php
index f43c835168c1d..e324a4e1b7bd5 100644
--- a/src/wp-admin/edit-form-blocks.php
+++ b/src/wp-admin/edit-form-blocks.php
@@ -203,7 +203,7 @@ static function( $classes ) {
 		'unlockNonce' => wp_create_nonce( 'update-post_' . $post->ID ),
 		'ajaxUrl'     => admin_url( 'admin-ajax.php' ),
 	),
-	'supportsLayout'       => WP_Theme_JSON_Resolver::theme_has_support(),
+	'supportsLayout'       => wp_theme_has_theme_json(),
 	'supportsTemplateMode' => current_theme_supports( 'block-templates' ),
 
 	// Whether or not to load the 'postcustom' meta box is stored as a user meta
diff --git a/src/wp-admin/site-editor.php b/src/wp-admin/site-editor.php
index a8b43b52af768..deb556a695768 100644
--- a/src/wp-admin/site-editor.php
+++ b/src/wp-admin/site-editor.php
@@ -74,7 +74,7 @@ static function( $classes ) {
 	'styles'                    => get_block_editor_theme_styles(),
 	'defaultTemplateTypes'      => $indexed_template_types,
 	'defaultTemplatePartAreas'  => get_allowed_block_template_part_areas(),
-	'supportsLayout'            => WP_Theme_JSON_Resolver::theme_has_support(),
+	'supportsLayout'            => wp_theme_has_theme_json(),
 	'supportsTemplatePartsMode' => ! wp_is_block_theme() && current_theme_supports( 'block-template-parts' ),
 	'__unstableHomeTemplate'    => $home_template,
 );
diff --git a/src/wp-includes/block-editor.php b/src/wp-includes/block-editor.php
index 7af9f2a90062a..4227c674c02ff 100644
--- a/src/wp-includes/block-editor.php
+++ b/src/wp-includes/block-editor.php
@@ -417,7 +417,7 @@ function get_block_editor_settings( array $custom_settings, $block_editor_contex
 		}
 	}
 
-	if ( WP_Theme_JSON_Resolver::theme_has_support() ) {
+	if ( wp_theme_has_theme_json() ) {
 		$block_classes = array(
 			'css'            => 'styles',
 			'__unstableType' => 'theme',
diff --git a/src/wp-includes/block-patterns.php b/src/wp-includes/block-patterns.php
index 074ed33c84b44..63398513d48dc 100644
--- a/src/wp-includes/block-patterns.php
+++ b/src/wp-includes/block-patterns.php
@@ -139,7 +139,7 @@ function _register_remote_theme_patterns() {
 		return;
 	}
 
-	if ( ! WP_Theme_JSON_Resolver::theme_has_support() ) {
+	if ( ! wp_theme_has_theme_json() ) {
 		return;
 	}
 
diff --git a/src/wp-includes/block-supports/layout.php b/src/wp-includes/block-supports/layout.php
index 7a882a9bab386..93c7364a323b6 100644
--- a/src/wp-includes/block-supports/layout.php
+++ b/src/wp-includes/block-supports/layout.php
@@ -464,7 +464,7 @@ function wp_restore_group_inner_container( $block_content, $block ) {
 	);
 
 	if (
-		WP_Theme_JSON_Resolver::theme_has_support() ||
+		wp_theme_has_theme_json() ||
 		1 === preg_match( $group_with_inner_container_regex, $block_content ) ||
 		( isset( $block['attrs']['layout']['type'] ) && 'flex' === $block['attrs']['layout']['type'] )
 	) {
@@ -527,7 +527,7 @@ function wp_restore_image_outer_container( $block_content, $block ) {
 )/iUx";
 
 	if (
-		WP_Theme_JSON_Resolver::theme_has_support() ||
+		wp_theme_has_theme_json() ||
 		0 === preg_match( $image_with_align, $block_content, $matches )
 	) {
 		return $block_content;
diff --git a/src/wp-includes/block-template-utils.php b/src/wp-includes/block-template-utils.php
index 826237aa18946..66c48db7f1305 100644
--- a/src/wp-includes/block-template-utils.php
+++ b/src/wp-includes/block-template-utils.php
@@ -347,7 +347,7 @@ function _get_block_templates_files( $template_type ) {
  * @return array Template item.
  */
 function _add_block_template_info( $template_item ) {
-	if ( ! WP_Theme_JSON_Resolver::theme_has_support() ) {
+	if ( ! wp_theme_has_theme_json() ) {
 		return $template_item;
 	}
 
@@ -370,7 +370,7 @@ function _add_block_template_info( $template_item ) {
  * @return array Template info.
  */
 function _add_block_template_part_area_info( $template_info ) {
-	if ( WP_Theme_JSON_Resolver::theme_has_support() ) {
+	if ( wp_theme_has_theme_json() ) {
 		$theme_data = WP_Theme_JSON_Resolver::get_theme_data( array(), array( 'with_supports' => false ) )->get_template_parts();
 	}
 
diff --git a/src/wp-includes/class-wp-theme-json-resolver.php b/src/wp-includes/class-wp-theme-json-resolver.php
index b1f15897b1af5..dda55ff00153c 100644
--- a/src/wp-includes/class-wp-theme-json-resolver.php
+++ b/src/wp-includes/class-wp-theme-json-resolver.php
@@ -57,14 +57,6 @@ class WP_Theme_JSON_Resolver {
 	 */
 	protected static $theme = null;
 
-	/**
-	 * Whether or not the theme supports theme.json.
-	 *
-	 * @since 5.8.0
-	 * @var bool
-	 */
-	protected static $theme_has_support = null;
-
 	/**
 	 * Container for data coming from the user.
 	 *
@@ -295,7 +287,7 @@ public static function get_theme_data( $deprecated = array(), $options = array()
 		 * and merge the static::$theme upon that.
 		 */
 		$theme_support_data = WP_Theme_JSON::get_from_editor_settings( get_default_block_editor_settings() );
-		if ( ! static::theme_has_support() ) {
+		if ( ! wp_theme_has_theme_json() ) {
 			if ( ! isset( $theme_support_data['settings']['color'] ) ) {
 				$theme_support_data['settings']['color'] = array();
 			}
@@ -416,11 +408,11 @@ public static function get_user_data_from_wp_global_styles( $theme, $create_post
 		/*
 		 * Bail early if the theme does not support a theme.json.
 		 *
-		 * Since WP_Theme_JSON_Resolver::theme_has_support() only supports the active
+		 * Since wp_theme_has_theme_json() only supports the active
 		 * theme, the extra condition for whether $theme is the active theme is
 		 * present here.
 		 */
-		if ( $theme->get_stylesheet() === get_stylesheet() && ! static::theme_has_support() ) {
+		if ( $theme->get_stylesheet() === get_stylesheet() && ! wp_theme_has_theme_json() ) {
 			return array();
 		}
 
@@ -597,18 +589,14 @@ public static function get_user_global_styles_post_id() {
 	 *
 	 * @since 5.8.0
 	 * @since 5.9.0 Added a check in the parent theme.
+	 * @deprecated 6.2.0 Use wp_theme_has_theme_json() instead.
 	 *
 	 * @return bool
 	 */
 	public static function theme_has_support() {
-		if ( ! isset( static::$theme_has_support ) ) {
-			static::$theme_has_support = (
-				static::get_file_path_from_theme( 'theme.json' ) !== '' ||
-				static::get_file_path_from_theme( 'theme.json', true ) !== ''
-			);
-		}
+		_deprecated_function( __METHOD__, '6.2.0', 'wp_theme_has_theme_json()' );
 
-		return static::$theme_has_support;
+		return wp_theme_has_theme_json();
 	}
 
 	/**
@@ -651,7 +639,6 @@ public static function clean_cached_data() {
 		static::$theme                    = null;
 		static::$user                     = null;
 		static::$user_custom_post_type_id = null;
-		static::$theme_has_support        = null;
 		static::$i18n_schema              = null;
 	}
 
diff --git a/src/wp-includes/global-styles-and-settings.php b/src/wp-includes/global-styles-and-settings.php
index 96fac51ce9e61..8492e6395a74a 100644
--- a/src/wp-includes/global-styles-and-settings.php
+++ b/src/wp-includes/global-styles-and-settings.php
@@ -102,7 +102,7 @@ function wp_get_global_stylesheet( $types = array() ) {
 
 	$tree = WP_Theme_JSON_Resolver::get_merged_data();
 
-	$supports_theme_json = WP_Theme_JSON_Resolver::theme_has_support();
+	$supports_theme_json = wp_theme_has_theme_json();
 	if ( empty( $types ) && ! $supports_theme_json ) {
 		$types = array( 'variables', 'presets', 'base-layout-styles' );
 	} elseif ( empty( $types ) ) {
@@ -184,7 +184,7 @@ function wp_get_global_styles_svg_filters() {
 		}
 	}
 
-	$supports_theme_json = WP_Theme_JSON_Resolver::theme_has_support();
+	$supports_theme_json = wp_theme_has_theme_json();
 
 	$origins = array( 'default', 'theme', 'custom' );
 	if ( ! $supports_theme_json ) {
diff --git a/src/wp-includes/script-loader.php b/src/wp-includes/script-loader.php
index 27defd0659460..ab693a3f22b13 100644
--- a/src/wp-includes/script-loader.php
+++ b/src/wp-includes/script-loader.php
@@ -1618,7 +1618,7 @@ function wp_default_styles( $styles ) {
 	);
 
 	// Only load the default layout and margin styles for themes without theme.json file.
-	if ( ! WP_Theme_JSON_Resolver::theme_has_support() ) {
+	if ( ! wp_theme_has_theme_json() ) {
 		$wp_edit_blocks_dependencies[] = 'wp-editor-classic-layout-styles';
 	}
 
@@ -3665,7 +3665,7 @@ function _wp_theme_json_webfonts_handler() {
  * @since 6.1.0
  */
 function wp_enqueue_classic_theme_styles() {
-	if ( ! WP_Theme_JSON_Resolver::theme_has_support() ) {
+	if ( ! wp_theme_has_theme_json() ) {
 		$suffix = wp_scripts_get_suffix();
 		wp_register_style( 'classic-theme-styles', '/' . WPINC . "/css/classic-themes$suffix.css", array(), true );
 		wp_enqueue_style( 'classic-theme-styles' );
@@ -3683,7 +3683,7 @@ function wp_enqueue_classic_theme_styles() {
  * @return array A filtered array of editor settings.
  */
 function wp_add_editor_classic_theme_styles( $editor_settings ) {
-	if ( WP_Theme_JSON_Resolver::theme_has_support() ) {
+	if ( wp_theme_has_theme_json() ) {
 		return $editor_settings;
 	}
 
diff --git a/src/wp-includes/theme-templates.php b/src/wp-includes/theme-templates.php
index 7ef010eea5ffd..ae71852a370e0 100644
--- a/src/wp-includes/theme-templates.php
+++ b/src/wp-includes/theme-templates.php
@@ -209,7 +209,7 @@ function the_block_template_skip_link() {
  * @since 5.8.0
  */
 function wp_enable_block_templates() {
-	if ( wp_is_block_theme() || WP_Theme_JSON_Resolver::theme_has_support() ) {
+	if ( wp_is_block_theme() || wp_theme_has_theme_json() ) {
 		add_theme_support( 'block-templates' );
 	}
 }
diff --git a/tests/phpunit/tests/theme/wpThemeJsonResolver.php b/tests/phpunit/tests/theme/wpThemeJsonResolver.php
index cd71b889e1c97..830704c07ba07 100644
--- a/tests/phpunit/tests/theme/wpThemeJsonResolver.php
+++ b/tests/phpunit/tests/theme/wpThemeJsonResolver.php
@@ -477,7 +477,7 @@ public function test_add_theme_supports_are_loaded_for_themes_without_theme_json
 		remove_theme_support( 'custom-line-height' );
 		remove_theme_support( 'editor-color-palette' );
 
-		$this->assertFalse( WP_Theme_JSON_Resolver::theme_has_support() );
+		$this->assertFalse( wp_theme_has_theme_json() );
 		$this->assertTrue( $settings['typography']['lineHeight'] );
 		$this->assertSame( $color_palette, $settings['color']['palette']['theme'] );
 	}

From 5b09d4dcdd155c93bd862ad8af638462c3f79cba Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andr=C3=A9?= <583546+oandregal@users.noreply.github.com>
Date: Tue, 13 Dec 2022 17:46:25 +0100
Subject: [PATCH 03/15] Add tests

---
 .../block-theme-child-no-theme-json/style.css |  8 ++
 .../default-child-no-theme-json/style.css     |  8 ++
 tests/phpunit/tests/theme/themeDir.php        |  2 +
 .../tests/theme/wpThemeHasThemeJson.php       | 86 +++++++++++++++++++
 .../tests/theme/wpThemeJsonResolver.php       | 16 ----
 5 files changed, 104 insertions(+), 16 deletions(-)
 create mode 100644 tests/phpunit/data/themedir1/block-theme-child-no-theme-json/style.css
 create mode 100644 tests/phpunit/data/themedir1/default-child-no-theme-json/style.css
 create mode 100644 tests/phpunit/tests/theme/wpThemeHasThemeJson.php

diff --git a/tests/phpunit/data/themedir1/block-theme-child-no-theme-json/style.css b/tests/phpunit/data/themedir1/block-theme-child-no-theme-json/style.css
new file mode 100644
index 0000000000000..344441288258e
--- /dev/null
+++ b/tests/phpunit/data/themedir1/block-theme-child-no-theme-json/style.css
@@ -0,0 +1,8 @@
+/*
+Theme Name: Block Theme Child with no theme.json
+Theme URI: https://wordpress.org/
+Description: For testing purposes only.
+Template: block-theme
+Version: 1.0.0
+Text Domain: block-theme-child-no-theme-json
+*/
diff --git a/tests/phpunit/data/themedir1/default-child-no-theme-json/style.css b/tests/phpunit/data/themedir1/default-child-no-theme-json/style.css
new file mode 100644
index 0000000000000..8f971990d9fec
--- /dev/null
+++ b/tests/phpunit/data/themedir1/default-child-no-theme-json/style.css
@@ -0,0 +1,8 @@
+/*
+Theme Name: Default Child Theme with no theme.json
+Theme URI: https://wordpress.org/
+Description: For testing purposes only.
+Template: default
+Version: 1.0.0
+Text Domain: default-child-no-theme-json
+*/
diff --git a/tests/phpunit/tests/theme/themeDir.php b/tests/phpunit/tests/theme/themeDir.php
index 29fbbd392f05a..270895c4426bd 100644
--- a/tests/phpunit/tests/theme/themeDir.php
+++ b/tests/phpunit/tests/theme/themeDir.php
@@ -163,6 +163,7 @@ public function test_theme_list() {
 		$theme_names = array_keys( $themes );
 		$expected    = array(
 			'WordPress Default',
+			'Default Child Theme with no theme.json',
 			'Sandbox',
 			'Stylesheet Only',
 			'My Theme',
@@ -177,6 +178,7 @@ public function test_theme_list() {
 			'REST Theme',
 			'Block Theme',
 			'Block Theme Child Theme',
+			'Block Theme Child with no theme.json',
 			'Block Theme Child Theme With Fluid Typography',
 			'Block Theme [0.4.0]',
 			'Block Theme [1.0.0] in subdirectory',
diff --git a/tests/phpunit/tests/theme/wpThemeHasThemeJson.php b/tests/phpunit/tests/theme/wpThemeHasThemeJson.php
new file mode 100644
index 0000000000000..a538562b8183f
--- /dev/null
+++ b/tests/phpunit/tests/theme/wpThemeHasThemeJson.php
@@ -0,0 +1,86 @@
+<?php
+
+require_once __DIR__ . '/base.php';
+
+/**
+ * Tests wp_theme_has_theme_json().
+ *
+ * @group theme_json
+ *
+ * @covers ::wp_theme_has_theme_json
+ */
+class Tests_Theme_WpThemeHasThemeJson extends WP_Theme_UnitTestCase {
+
+	/**
+	 * Test that it reports correctly themes that have a theme.json.
+	 *
+	 * @covers wp_theme_has_theme_json
+	 */
+	public function test_theme_has_theme_json() {
+		switch_theme( 'block-theme' );
+		$this->assertTrue( wp_theme_has_theme_json() );
+	}
+
+	/**
+	 * Test that it reports correctly themes that do not have a theme.json.
+	 *
+	 * @covers wp_theme_has_theme_json
+	 */
+	public function test_theme_has_no_theme_json() {
+		switch_theme( 'default' );
+		$this->assertFalse( wp_theme_has_theme_json() );
+	}
+
+	/**
+	 * Test it reports correctly child themes that have a theme.json.
+	 *
+	 * @covers wp_theme_has_theme_json
+	 */
+	public function test_child_theme_has_theme_json() {
+		switch_theme( 'block-theme-child' );
+		$this->assertTrue( wp_theme_has_theme_json() );
+	}
+
+	/**
+	 * Test that it reports correctly child themes that do not have a theme.json
+	 * and the parent does.
+	 *
+	 * @covers wp_theme_has_theme_json
+	 */
+	public function test_child_theme_has_not_theme_json_but_parent_has() {
+		switch_theme( 'block-theme-child-no-theme-json' );
+		$this->assertTrue( wp_theme_has_theme_json() );
+	}
+
+	/**
+	 * Test that it reports correctly child themes that do not have a theme.json
+	 * and the parent does not either.
+	 *
+	 * @covers wp_theme_has_theme_json
+	 */
+	public function test_neither_child_or_parent_themes_have_theme_json() {
+		switch_theme( 'default-child-no-theme-json' );
+		$this->assertFalse( wp_theme_has_theme_json() );
+	}
+
+	/**
+	 * Test that switching themes recalculates theme support.
+	 *
+	 * @ticket 52991
+	 *
+	 * @covers wp_theme_has_theme_json
+	 */
+	public function test_switching_themes_recalculates_support() {
+		// The "default" theme doesn't have theme.json support.
+		switch_theme( 'default' );
+		$default = wp_theme_has_theme_json();
+
+		// Switch to a theme that does have support.
+		switch_theme( 'block-theme' );
+		$block_theme = wp_theme_has_theme_json();
+
+		$this->assertFalse( $default );
+		$this->assertTrue( $block_theme );
+	}
+
+}
diff --git a/tests/phpunit/tests/theme/wpThemeJsonResolver.php b/tests/phpunit/tests/theme/wpThemeJsonResolver.php
index 830704c07ba07..8ae0548c4accb 100644
--- a/tests/phpunit/tests/theme/wpThemeJsonResolver.php
+++ b/tests/phpunit/tests/theme/wpThemeJsonResolver.php
@@ -431,22 +431,6 @@ public function data_get_core_data() {
 		);
 	}
 
-	/**
-	 * @ticket 52991
-	 */
-	public function test_switching_themes_recalculates_data() {
-		// The "default" theme doesn't have theme.json support.
-		switch_theme( 'default' );
-		$default = WP_Theme_JSON_Resolver::theme_has_support();
-
-		// Switch to a theme that does have support.
-		switch_theme( 'block-theme' );
-		$has_theme_json_support = WP_Theme_JSON_Resolver::theme_has_support();
-
-		$this->assertFalse( $default );
-		$this->assertTrue( $has_theme_json_support );
-	}
-
 	/**
 	 * @ticket 54336
 	 */

From 3dfbad3a4d41f69dbbac15c10397ce504715546b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andr=C3=A9?= <583546+oandregal@users.noreply.github.com>
Date: Tue, 13 Dec 2022 18:04:27 +0100
Subject: [PATCH 04/15] Port cache group management from PR 3712

---
 src/wp-includes/default-filters.php           |  4 +--
 .../global-styles-and-settings.php            | 27 +++++++++++++++++++
 src/wp-includes/load.php                      |  2 +-
 src/wp-includes/ms-blogs.php                  |  4 +--
 tests/phpunit/includes/abstract-testcase.php  |  2 +-
 5 files changed, 33 insertions(+), 6 deletions(-)

diff --git a/src/wp-includes/default-filters.php b/src/wp-includes/default-filters.php
index 5c623e371b195..2155300e3b7aa 100644
--- a/src/wp-includes/default-filters.php
+++ b/src/wp-includes/default-filters.php
@@ -346,8 +346,8 @@
 add_action( 'init', '_register_core_block_patterns_and_categories' );
 add_action( 'init', 'check_theme_switched', 99 );
 add_action( 'init', array( 'WP_Block_Supports', 'init' ), 22 );
-add_action( 'switch_theme', array( 'WP_Theme_JSON_Resolver', 'clean_cached_data' ) );
-add_action( 'start_previewing_theme', array( 'WP_Theme_JSON_Resolver', 'clean_cached_data' ) );
+add_action( 'switch_theme', '_wp_clean_theme_json_caches' );
+add_action( 'start_previewing_theme', '_wp_clean_theme_json_caches' );
 add_action( 'after_switch_theme', '_wp_menus_changed' );
 add_action( 'after_switch_theme', '_wp_sidebars_changed' );
 add_action( 'wp_print_styles', 'print_emoji_styles' );
diff --git a/src/wp-includes/global-styles-and-settings.php b/src/wp-includes/global-styles-and-settings.php
index 8492e6395a74a..643f030a0c2fe 100644
--- a/src/wp-includes/global-styles-and-settings.php
+++ b/src/wp-includes/global-styles-and-settings.php
@@ -264,6 +264,22 @@ function ( $item ) {
  * @return boolean
  */
 function wp_theme_has_theme_json() {
+	/**
+	 * By using the 'theme_json' group, this data is marked to be non-persistent across requests.
+	 * See `wp_cache_add_non_persistent_groups` in src/wp-includes/load.php and other places.
+	 *
+	 * The rationale for this is to make sure derived data from theme.json
+	 * is always fresh from the potential modifications done via hooks
+	 * that can use dynamic data (modify the stylesheet depending on some option,
+	 * settings depending on user permissions, etc.).
+	 * See some of the existing hooks to modify theme.json behaviour:
+	 * https://make.wordpress.org/core/2022/10/10/filters-for-theme-json-data/
+	 *
+	 * A different alternative considered was to invalidate the cache upon certain
+	 * events such as options add/update/delete, user meta, etc.
+	 * It was judged not enough, hence this approach.
+	 * See https://github.com/WordPress/gutenberg/pull/45372
+	 */
 	$cache_group       = 'theme_json';
 	$cache_key         = 'wp_theme_has_theme_json';
 	$theme_has_support = wp_cache_get( $cache_key, $cache_group );
@@ -295,3 +311,14 @@ function wp_theme_has_theme_json() {
 
 	return (bool) $theme_has_support;
 }
+
+/**
+ * Private function to clean the caches under the theme_json group.
+ *
+ * @since 6.1.2
+ * @access private
+ */
+function _wp_clean_theme_json_caches() {
+	wp_cache_delete( 'wp_theme_has_theme_json', 'theme_json' );
+	WP_Theme_JSON_Resolver::clean_cached_data();
+}
\ No newline at end of file
diff --git a/src/wp-includes/load.php b/src/wp-includes/load.php
index 4c212086df34e..c2450e582f958 100644
--- a/src/wp-includes/load.php
+++ b/src/wp-includes/load.php
@@ -753,7 +753,7 @@ function wp_start_object_cache() {
 			)
 		);
 
-		wp_cache_add_non_persistent_groups( array( 'counts', 'plugins' ) );
+		wp_cache_add_non_persistent_groups( array( 'counts', 'plugins', 'theme_json' ) );
 	}
 
 	$first_init = false;
diff --git a/src/wp-includes/ms-blogs.php b/src/wp-includes/ms-blogs.php
index 0ea6f85627dcb..7ff830e930863 100644
--- a/src/wp-includes/ms-blogs.php
+++ b/src/wp-includes/ms-blogs.php
@@ -575,7 +575,7 @@ function switch_to_blog( $new_blog_id, $deprecated = null ) {
 				);
 			}
 
-			wp_cache_add_non_persistent_groups( array( 'counts', 'plugins' ) );
+			wp_cache_add_non_persistent_groups( array( 'counts', 'plugins', 'theme_json' ) );
 		}
 	}
 
@@ -666,7 +666,7 @@ function restore_current_blog() {
 				);
 			}
 
-			wp_cache_add_non_persistent_groups( array( 'counts', 'plugins' ) );
+			wp_cache_add_non_persistent_groups( array( 'counts', 'plugins', 'theme_json' ) );
 		}
 	}
 
diff --git a/tests/phpunit/includes/abstract-testcase.php b/tests/phpunit/includes/abstract-testcase.php
index 6cfeaa307cc26..33df37ad44331 100644
--- a/tests/phpunit/includes/abstract-testcase.php
+++ b/tests/phpunit/includes/abstract-testcase.php
@@ -401,7 +401,7 @@ public static function flush_cache() {
 			)
 		);
 
-		wp_cache_add_non_persistent_groups( array( 'counts', 'plugins' ) );
+		wp_cache_add_non_persistent_groups( array( 'counts', 'plugins', 'theme_json' ) );
 	}
 
 	/**

From 04d72eeddfe3eb4b68d0329066a6ae326f722103 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andr=C3=A9?= <583546+oandregal@users.noreply.github.com>
Date: Tue, 13 Dec 2022 18:13:53 +0100
Subject: [PATCH 05/15] Substitute call to clean_cached_data by
 _wp_clean_theme_json_caches

---
 tests/phpunit/tests/theme/wpThemeJsonResolver.php      | 10 +++++-----
 .../tests/webfonts/wpThemeJsonWebfontsHandler.php      |  2 +-
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/tests/phpunit/tests/theme/wpThemeJsonResolver.php b/tests/phpunit/tests/theme/wpThemeJsonResolver.php
index 8ae0548c4accb..200088f85c55a 100644
--- a/tests/phpunit/tests/theme/wpThemeJsonResolver.php
+++ b/tests/phpunit/tests/theme/wpThemeJsonResolver.php
@@ -110,7 +110,7 @@ public function tear_down() {
 		unset( $GLOBALS['wp_themes'] );
 
 		// Reset data between tests.
-		WP_Theme_JSON_Resolver::clean_cached_data();
+		_wp_clean_theme_json_caches();
 		parent::tear_down();
 	}
 
@@ -376,7 +376,7 @@ public function data_has_same_registered_blocks_when_all_blocks_are_cached() {
 	 * @ticket 56467
 	 */
 	public function test_get_core_data( $should_fire_filter, $core_is_cached, $blocks_are_cached ) {
-		WP_Theme_JSON_Resolver::clean_cached_data();
+		_wp_clean_theme_json_caches();
 
 		// If should cache core, then fire the method to cache it before running the tests.
 		if ( $core_is_cached ) {
@@ -621,7 +621,7 @@ function( $query ) use ( &$global_styles_query_count ) {
 		);
 		for ( $i = 0; $i < 3; $i++ ) {
 			WP_Theme_JSON_Resolver::get_user_data_from_wp_global_styles( $theme );
-			WP_Theme_JSON_Resolver::clean_cached_data();
+			_wp_clean_theme_json_caches();
 		}
 		$this->assertSame( 0, $global_styles_query_count, 'Unexpected SQL queries detected for the wp_global_style post type prior to creation.' );
 
@@ -634,7 +634,7 @@ function( $query ) use ( &$global_styles_query_count ) {
 		$global_styles_query_count = 0;
 		for ( $i = 0; $i < 3; $i++ ) {
 			$new_user_cpt = WP_Theme_JSON_Resolver::get_user_data_from_wp_global_styles( $theme );
-			WP_Theme_JSON_Resolver::clean_cached_data();
+			_wp_clean_theme_json_caches();
 			$this->assertSameSets( $user_cpt, $new_user_cpt, "User CPTs do not match on run {$i}." );
 		}
 		$this->assertSame( 1, $global_styles_query_count, 'Unexpected SQL queries detected for the wp_global_style post type after creation.' );
@@ -651,7 +651,7 @@ public function test_get_user_data_from_wp_global_styles_does_not_use_uncached_q
 		$query_count = get_num_queries();
 		for ( $i = 0; $i < 3; $i++ ) {
 			WP_Theme_JSON_Resolver::get_user_data_from_wp_global_styles( $theme );
-			WP_Theme_JSON_Resolver::clean_cached_data();
+			_wp_clean_theme_json_caches();
 		}
 		$query_count = get_num_queries() - $query_count;
 		$this->assertSame( 0, $query_count, 'Unexpected SQL queries detected for the wp_global_style post type prior to creation.' );
diff --git a/tests/phpunit/tests/webfonts/wpThemeJsonWebfontsHandler.php b/tests/phpunit/tests/webfonts/wpThemeJsonWebfontsHandler.php
index 5c609923d7b39..30df269803d2d 100644
--- a/tests/phpunit/tests/webfonts/wpThemeJsonWebfontsHandler.php
+++ b/tests/phpunit/tests/webfonts/wpThemeJsonWebfontsHandler.php
@@ -129,7 +129,7 @@ public function data_font_face_not_generated() {
 	private function setup_theme_and_test( $theme_name ) {
 		switch_theme( $theme_name );
 		do_action( 'after_setup_theme' );
-		WP_Theme_JSON_Resolver::clean_cached_data();
+		_wp_clean_theme_json_caches();
 		do_action( 'wp_loaded' );
 		do_action( 'wp_enqueue_scripts' );
 	}

From 771a347095ed1d2cadeb38749415dfaa0c0b0eb0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andr=C3=A9?= <583546+oandregal@users.noreply.github.com>
Date: Tue, 13 Dec 2022 18:23:55 +0100
Subject: [PATCH 06/15] Fix lint issue

---
 src/wp-includes/global-styles-and-settings.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/wp-includes/global-styles-and-settings.php b/src/wp-includes/global-styles-and-settings.php
index 643f030a0c2fe..1fe17ec0a9ec5 100644
--- a/src/wp-includes/global-styles-and-settings.php
+++ b/src/wp-includes/global-styles-and-settings.php
@@ -321,4 +321,4 @@ function wp_theme_has_theme_json() {
 function _wp_clean_theme_json_caches() {
 	wp_cache_delete( 'wp_theme_has_theme_json', 'theme_json' );
 	WP_Theme_JSON_Resolver::clean_cached_data();
-}
\ No newline at end of file
+}

From 5d5c69fa57376414cabff06b44cc3dd29a1ae91d Mon Sep 17 00:00:00 2001
From: costdev <me@colin-stewart.co.uk>
Date: Wed, 14 Dec 2022 10:14:58 +0100
Subject: [PATCH 07/15] Fix lint issues

---
 src/wp-includes/global-styles-and-settings.php    |  8 ++++----
 tests/phpunit/tests/theme/wpThemeHasThemeJson.php | 11 -----------
 2 files changed, 4 insertions(+), 15 deletions(-)

diff --git a/src/wp-includes/global-styles-and-settings.php b/src/wp-includes/global-styles-and-settings.php
index 1fe17ec0a9ec5..e881403d45c27 100644
--- a/src/wp-includes/global-styles-and-settings.php
+++ b/src/wp-includes/global-styles-and-settings.php
@@ -261,10 +261,10 @@ function ( $item ) {
  *
  * @since 6.2.0
  *
- * @return boolean
+ * @return bool
  */
 function wp_theme_has_theme_json() {
-	/**
+	/*
 	 * By using the 'theme_json' group, this data is marked to be non-persistent across requests.
 	 * See `wp_cache_add_non_persistent_groups` in src/wp-includes/load.php and other places.
 	 *
@@ -284,7 +284,7 @@ function wp_theme_has_theme_json() {
 	$cache_key         = 'wp_theme_has_theme_json';
 	$theme_has_support = wp_cache_get( $cache_key, $cache_group );
 
-	/**
+	/*
 	 * $theme_has_support is stored as an int in the cache.
 	 *
 	 * The reason not to store it as a boolean is to avoid working
@@ -297,7 +297,7 @@ function wp_theme_has_theme_json() {
 		return (bool) $theme_has_support;
 	}
 
-	// Has the own theme a theme.json?
+	// Does the theme have its own theme.json?
 	$theme_has_support = is_readable( get_stylesheet_directory() . '/theme.json' );
 
 	// Look up the parent if the child does not have a theme.json.
diff --git a/tests/phpunit/tests/theme/wpThemeHasThemeJson.php b/tests/phpunit/tests/theme/wpThemeHasThemeJson.php
index a538562b8183f..fcbe4e3f3d05b 100644
--- a/tests/phpunit/tests/theme/wpThemeHasThemeJson.php
+++ b/tests/phpunit/tests/theme/wpThemeHasThemeJson.php
@@ -13,8 +13,6 @@ class Tests_Theme_WpThemeHasThemeJson extends WP_Theme_UnitTestCase {
 
 	/**
 	 * Test that it reports correctly themes that have a theme.json.
-	 *
-	 * @covers wp_theme_has_theme_json
 	 */
 	public function test_theme_has_theme_json() {
 		switch_theme( 'block-theme' );
@@ -23,8 +21,6 @@ public function test_theme_has_theme_json() {
 
 	/**
 	 * Test that it reports correctly themes that do not have a theme.json.
-	 *
-	 * @covers wp_theme_has_theme_json
 	 */
 	public function test_theme_has_no_theme_json() {
 		switch_theme( 'default' );
@@ -33,8 +29,6 @@ public function test_theme_has_no_theme_json() {
 
 	/**
 	 * Test it reports correctly child themes that have a theme.json.
-	 *
-	 * @covers wp_theme_has_theme_json
 	 */
 	public function test_child_theme_has_theme_json() {
 		switch_theme( 'block-theme-child' );
@@ -44,8 +38,6 @@ public function test_child_theme_has_theme_json() {
 	/**
 	 * Test that it reports correctly child themes that do not have a theme.json
 	 * and the parent does.
-	 *
-	 * @covers wp_theme_has_theme_json
 	 */
 	public function test_child_theme_has_not_theme_json_but_parent_has() {
 		switch_theme( 'block-theme-child-no-theme-json' );
@@ -55,8 +47,6 @@ public function test_child_theme_has_not_theme_json_but_parent_has() {
 	/**
 	 * Test that it reports correctly child themes that do not have a theme.json
 	 * and the parent does not either.
-	 *
-	 * @covers wp_theme_has_theme_json
 	 */
 	public function test_neither_child_or_parent_themes_have_theme_json() {
 		switch_theme( 'default-child-no-theme-json' );
@@ -68,7 +58,6 @@ public function test_neither_child_or_parent_themes_have_theme_json() {
 	 *
 	 * @ticket 52991
 	 *
-	 * @covers wp_theme_has_theme_json
 	 */
 	public function test_switching_themes_recalculates_support() {
 		// The "default" theme doesn't have theme.json support.

From 16b5d6ce738c12e20012bee0a61726b4ca7df147 Mon Sep 17 00:00:00 2001
From: costdev <me@colin-stewart.co.uk>
Date: Wed, 14 Dec 2022 10:23:38 +0100
Subject: [PATCH 08/15] Improve tests

---
 tests/phpunit/tests/theme/wpThemeHasThemeJson.php | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/phpunit/tests/theme/wpThemeHasThemeJson.php b/tests/phpunit/tests/theme/wpThemeHasThemeJson.php
index fcbe4e3f3d05b..77691de1cc40f 100644
--- a/tests/phpunit/tests/theme/wpThemeHasThemeJson.php
+++ b/tests/phpunit/tests/theme/wpThemeHasThemeJson.php
@@ -68,8 +68,8 @@ public function test_switching_themes_recalculates_support() {
 		switch_theme( 'block-theme' );
 		$block_theme = wp_theme_has_theme_json();
 
-		$this->assertFalse( $default );
-		$this->assertTrue( $block_theme );
+		$this->assertFalse( $default, 'The "default" theme should not report theme.json support.' );
+		$this->assertTrue ( $block_theme, 'The block theme should report theme.json support.' );
 	}
 
 }

From 88418422b0320b23ed36317089ccbb0341051d97 Mon Sep 17 00:00:00 2001
From: costdev <me@colin-stewart.co.uk>
Date: Wed, 14 Dec 2022 10:37:13 +0100
Subject: [PATCH 09/15] Use data provider in tests

---
 .../tests/theme/wpThemeHasThemeJson.php       | 73 ++++++++++---------
 1 file changed, 37 insertions(+), 36 deletions(-)

diff --git a/tests/phpunit/tests/theme/wpThemeHasThemeJson.php b/tests/phpunit/tests/theme/wpThemeHasThemeJson.php
index 77691de1cc40f..b74403124dbf5 100644
--- a/tests/phpunit/tests/theme/wpThemeHasThemeJson.php
+++ b/tests/phpunit/tests/theme/wpThemeHasThemeJson.php
@@ -12,49 +12,50 @@
 class Tests_Theme_WpThemeHasThemeJson extends WP_Theme_UnitTestCase {
 
 	/**
-	 * Test that it reports correctly themes that have a theme.json.
-	 */
-	public function test_theme_has_theme_json() {
-		switch_theme( 'block-theme' );
-		$this->assertTrue( wp_theme_has_theme_json() );
-	}
-
-	/**
-	 * Test that it reports correctly themes that do not have a theme.json.
-	 */
-	public function test_theme_has_no_theme_json() {
-		switch_theme( 'default' );
-		$this->assertFalse( wp_theme_has_theme_json() );
-	}
-
-	/**
-	 * Test it reports correctly child themes that have a theme.json.
-	 */
-	public function test_child_theme_has_theme_json() {
-		switch_theme( 'block-theme-child' );
-		$this->assertTrue( wp_theme_has_theme_json() );
-	}
-
-	/**
-	 * Test that it reports correctly child themes that do not have a theme.json
-	 * and the parent does.
+	 * Tests that wp_theme_has_theme_json() correctly reports whether a theme has a theme.json file.
+	 *
+	 * @dataProvider data_theme_has_theme_json_reports_correctly
+	 *
+	 * @param string $theme    The slug of the theme to switch to.
+	 * @param bool   $expected The expected result.
 	 */
-	public function test_child_theme_has_not_theme_json_but_parent_has() {
-		switch_theme( 'block-theme-child-no-theme-json' );
-		$this->assertTrue( wp_theme_has_theme_json() );
+	public function test_theme_has_theme_json_reports_correctly( $theme, $expected ) {
+		switch_theme( $theme );
+		$this->assertSame( $expected, wp_theme_has_theme_json() );
 	}
 
 	/**
-	 * Test that it reports correctly child themes that do not have a theme.json
-	 * and the parent does not either.
+	 * Data provider for test_theme_has_theme_json_reports_correctly().
+	 *
+	 * @return array[]
 	 */
-	public function test_neither_child_or_parent_themes_have_theme_json() {
-		switch_theme( 'default-child-no-theme-json' );
-		$this->assertFalse( wp_theme_has_theme_json() );
+	public function data_theme_has_theme_json_reports_correctly() {
+		return array(
+			'a theme with theme.json'       => array(
+				'theme'    => 'block-theme',
+				'expected' => true,
+			),
+			'a theme without theme.json'    => array(
+				'theme'    => 'default',
+				'expected' => false,
+			),
+			'a child theme with theme.json' => array(
+				'theme'    => 'block-theme-child',
+				'expected' => true,
+			),
+			'a child theme without theme.json and parent theme with theme.json' => array(
+				'theme'    => 'block-theme-child-no-theme-json',
+				'expected' => true,
+			),
+			'a child theme without theme.json and parent theme without theme.json' => array(
+				'theme'    => 'default-child-no-theme-json',
+				'expected' => false,
+			),
+		);
 	}
 
 	/**
-	 * Test that switching themes recalculates theme support.
+	 * Tests that switching themes recalculates theme support.
 	 *
 	 * @ticket 52991
 	 *
@@ -69,7 +70,7 @@ public function test_switching_themes_recalculates_support() {
 		$block_theme = wp_theme_has_theme_json();
 
 		$this->assertFalse( $default, 'The "default" theme should not report theme.json support.' );
-		$this->assertTrue ( $block_theme, 'The block theme should report theme.json support.' );
+		$this->assertTrue( $block_theme, 'The block theme should report theme.json support.' );
 	}
 
 }

From 860418295f2765a0649d42bc15a3e5d397dcc3a2 Mon Sep 17 00:00:00 2001
From: hellofromtonya <tonya.mork@automattic.com>
Date: Mon, 16 Jan 2023 15:00:52 -0600
Subject: [PATCH 10/15] Make wp_clean_theme_json_caches() public

---
 src/wp-includes/default-filters.php                    |  4 ++--
 src/wp-includes/global-styles-and-settings.php         |  7 +++----
 tests/phpunit/tests/theme/wpThemeJsonResolver.php      | 10 +++++-----
 .../tests/webfonts/wpThemeJsonWebfontsHandler.php      |  2 +-
 4 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/src/wp-includes/default-filters.php b/src/wp-includes/default-filters.php
index 2155300e3b7aa..bfb146c5a9424 100644
--- a/src/wp-includes/default-filters.php
+++ b/src/wp-includes/default-filters.php
@@ -346,8 +346,8 @@
 add_action( 'init', '_register_core_block_patterns_and_categories' );
 add_action( 'init', 'check_theme_switched', 99 );
 add_action( 'init', array( 'WP_Block_Supports', 'init' ), 22 );
-add_action( 'switch_theme', '_wp_clean_theme_json_caches' );
-add_action( 'start_previewing_theme', '_wp_clean_theme_json_caches' );
+add_action( 'switch_theme', 'wp_clean_theme_json_caches' );
+add_action( 'start_previewing_theme', 'wp_clean_theme_json_caches' );
 add_action( 'after_switch_theme', '_wp_menus_changed' );
 add_action( 'after_switch_theme', '_wp_sidebars_changed' );
 add_action( 'wp_print_styles', 'print_emoji_styles' );
diff --git a/src/wp-includes/global-styles-and-settings.php b/src/wp-includes/global-styles-and-settings.php
index e881403d45c27..7a546bb78fa2d 100644
--- a/src/wp-includes/global-styles-and-settings.php
+++ b/src/wp-includes/global-styles-and-settings.php
@@ -313,12 +313,11 @@ function wp_theme_has_theme_json() {
 }
 
 /**
- * Private function to clean the caches under the theme_json group.
+ * Cleans the caches under the theme_json group.
  *
- * @since 6.1.2
- * @access private
+ * @since 6.2.0
  */
-function _wp_clean_theme_json_caches() {
+function wp_clean_theme_json_caches() {
 	wp_cache_delete( 'wp_theme_has_theme_json', 'theme_json' );
 	WP_Theme_JSON_Resolver::clean_cached_data();
 }
diff --git a/tests/phpunit/tests/theme/wpThemeJsonResolver.php b/tests/phpunit/tests/theme/wpThemeJsonResolver.php
index 200088f85c55a..9dd72ee929c50 100644
--- a/tests/phpunit/tests/theme/wpThemeJsonResolver.php
+++ b/tests/phpunit/tests/theme/wpThemeJsonResolver.php
@@ -110,7 +110,7 @@ public function tear_down() {
 		unset( $GLOBALS['wp_themes'] );
 
 		// Reset data between tests.
-		_wp_clean_theme_json_caches();
+		wp_clean_theme_json_caches();
 		parent::tear_down();
 	}
 
@@ -376,7 +376,7 @@ public function data_has_same_registered_blocks_when_all_blocks_are_cached() {
 	 * @ticket 56467
 	 */
 	public function test_get_core_data( $should_fire_filter, $core_is_cached, $blocks_are_cached ) {
-		_wp_clean_theme_json_caches();
+		wp_clean_theme_json_caches();
 
 		// If should cache core, then fire the method to cache it before running the tests.
 		if ( $core_is_cached ) {
@@ -621,7 +621,7 @@ function( $query ) use ( &$global_styles_query_count ) {
 		);
 		for ( $i = 0; $i < 3; $i++ ) {
 			WP_Theme_JSON_Resolver::get_user_data_from_wp_global_styles( $theme );
-			_wp_clean_theme_json_caches();
+			wp_clean_theme_json_caches();
 		}
 		$this->assertSame( 0, $global_styles_query_count, 'Unexpected SQL queries detected for the wp_global_style post type prior to creation.' );
 
@@ -634,7 +634,7 @@ function( $query ) use ( &$global_styles_query_count ) {
 		$global_styles_query_count = 0;
 		for ( $i = 0; $i < 3; $i++ ) {
 			$new_user_cpt = WP_Theme_JSON_Resolver::get_user_data_from_wp_global_styles( $theme );
-			_wp_clean_theme_json_caches();
+			wp_clean_theme_json_caches();
 			$this->assertSameSets( $user_cpt, $new_user_cpt, "User CPTs do not match on run {$i}." );
 		}
 		$this->assertSame( 1, $global_styles_query_count, 'Unexpected SQL queries detected for the wp_global_style post type after creation.' );
@@ -651,7 +651,7 @@ public function test_get_user_data_from_wp_global_styles_does_not_use_uncached_q
 		$query_count = get_num_queries();
 		for ( $i = 0; $i < 3; $i++ ) {
 			WP_Theme_JSON_Resolver::get_user_data_from_wp_global_styles( $theme );
-			_wp_clean_theme_json_caches();
+			wp_clean_theme_json_caches();
 		}
 		$query_count = get_num_queries() - $query_count;
 		$this->assertSame( 0, $query_count, 'Unexpected SQL queries detected for the wp_global_style post type prior to creation.' );
diff --git a/tests/phpunit/tests/webfonts/wpThemeJsonWebfontsHandler.php b/tests/phpunit/tests/webfonts/wpThemeJsonWebfontsHandler.php
index 30df269803d2d..be8709cb71f22 100644
--- a/tests/phpunit/tests/webfonts/wpThemeJsonWebfontsHandler.php
+++ b/tests/phpunit/tests/webfonts/wpThemeJsonWebfontsHandler.php
@@ -129,7 +129,7 @@ public function data_font_face_not_generated() {
 	private function setup_theme_and_test( $theme_name ) {
 		switch_theme( $theme_name );
 		do_action( 'after_setup_theme' );
-		_wp_clean_theme_json_caches();
+		wp_clean_theme_json_caches();
 		do_action( 'wp_loaded' );
 		do_action( 'wp_enqueue_scripts' );
 	}

From 901e98a5e600d8ee0938e2115a21e2d29173eb28 Mon Sep 17 00:00:00 2001
From: hellofromtonya <tonya.mork@automattic.com>
Date: Mon, 16 Jan 2023 15:34:57 -0600
Subject: [PATCH 11/15] Comment improvements

---
 src/wp-includes/global-styles-and-settings.php | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/src/wp-includes/global-styles-and-settings.php b/src/wp-includes/global-styles-and-settings.php
index 7a546bb78fa2d..0eebe07cb1afe 100644
--- a/src/wp-includes/global-styles-and-settings.php
+++ b/src/wp-includes/global-styles-and-settings.php
@@ -257,28 +257,28 @@ function ( $item ) {
 }
 
 /**
- * Whether a theme or its parent have a theme.json file.
+ * Checks whether a theme or its parent has a theme.json file.
  *
  * @since 6.2.0
  *
- * @return bool
+ * @return bool Returns true if theme or its parent has a theme.json file, false otherwise.
  */
 function wp_theme_has_theme_json() {
 	/*
 	 * By using the 'theme_json' group, this data is marked to be non-persistent across requests.
-	 * See `wp_cache_add_non_persistent_groups` in src/wp-includes/load.php and other places.
+	 * @see `wp_cache_add_non_persistent_groups()`.
 	 *
 	 * The rationale for this is to make sure derived data from theme.json
 	 * is always fresh from the potential modifications done via hooks
 	 * that can use dynamic data (modify the stylesheet depending on some option,
 	 * settings depending on user permissions, etc.).
-	 * See some of the existing hooks to modify theme.json behaviour:
-	 * https://make.wordpress.org/core/2022/10/10/filters-for-theme-json-data/
+	 * For some of the existing hooks to modify theme.json behavior:
+	 * @see https://make.wordpress.org/core/2022/10/10/filters-for-theme-json-data/
 	 *
 	 * A different alternative considered was to invalidate the cache upon certain
 	 * events such as options add/update/delete, user meta, etc.
 	 * It was judged not enough, hence this approach.
-	 * See https://github.com/WordPress/gutenberg/pull/45372
+	 * @see https://github.com/WordPress/gutenberg/pull/45372
 	 */
 	$cache_group       = 'theme_json';
 	$cache_key         = 'wp_theme_has_theme_json';
@@ -289,9 +289,10 @@ function wp_theme_has_theme_json() {
 	 *
 	 * The reason not to store it as a boolean is to avoid working
 	 * with the $found parameter which apparently had some issues in some implementations
-	 * https://developer.wordpress.org/reference/functions/wp_cache_get/
+	 * @see https://developer.wordpress.org/reference/functions/wp_cache_get/
 	 *
-	 * Ignore cache when `WP_DEBUG` is enabled, so it doesn't interfere with the theme developers workflow.
+	 * Ignore cache when `WP_DEBUG` is enabled, so it doesn't interfere with the theme
+	 * developers workflow.
 	 */
 	if ( ! WP_DEBUG && is_int( $theme_has_support ) ) {
 		return (bool) $theme_has_support;

From cbcd7d29a9d1e68d62d6b3bda8a4f44473991564 Mon Sep 17 00:00:00 2001
From: hellofromtonya <tonya.mork@automattic.com>
Date: Mon, 16 Jan 2023 15:49:24 -0600
Subject: [PATCH 12/15] Test comment and annotation improvements

---
 tests/phpunit/tests/theme/wpThemeHasThemeJson.php | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/tests/phpunit/tests/theme/wpThemeHasThemeJson.php b/tests/phpunit/tests/theme/wpThemeHasThemeJson.php
index b74403124dbf5..636886c03bbcc 100644
--- a/tests/phpunit/tests/theme/wpThemeHasThemeJson.php
+++ b/tests/phpunit/tests/theme/wpThemeHasThemeJson.php
@@ -12,7 +12,7 @@
 class Tests_Theme_WpThemeHasThemeJson extends WP_Theme_UnitTestCase {
 
 	/**
-	 * Tests that wp_theme_has_theme_json() correctly reports whether a theme has a theme.json file.
+	 * @ticket 56975
 	 *
 	 * @dataProvider data_theme_has_theme_json_reports_correctly
 	 *
@@ -25,7 +25,7 @@ public function test_theme_has_theme_json_reports_correctly( $theme, $expected )
 	}
 
 	/**
-	 * Data provider for test_theme_has_theme_json_reports_correctly().
+	 * Data provider.
 	 *
 	 * @return array[]
 	 */
@@ -55,10 +55,7 @@ public function data_theme_has_theme_json_reports_correctly() {
 	}
 
 	/**
-	 * Tests that switching themes recalculates theme support.
-	 *
 	 * @ticket 52991
-	 *
 	 */
 	public function test_switching_themes_recalculates_support() {
 		// The "default" theme doesn't have theme.json support.
@@ -72,5 +69,4 @@ public function test_switching_themes_recalculates_support() {
 		$this->assertFalse( $default, 'The "default" theme should not report theme.json support.' );
 		$this->assertTrue( $block_theme, 'The block theme should report theme.json support.' );
 	}
-
 }

From 91d6ec67796ae8854de9e8978e7285de950166a5 Mon Sep 17 00:00:00 2001
From: hellofromtonya <tonya.mork@automattic.com>
Date: Tue, 17 Jan 2023 14:53:43 -0600
Subject: [PATCH 13/15] Add TODO note

---
 src/wp-includes/global-styles-and-settings.php | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/wp-includes/global-styles-and-settings.php b/src/wp-includes/global-styles-and-settings.php
index 0eebe07cb1afe..14a11ff578646 100644
--- a/src/wp-includes/global-styles-and-settings.php
+++ b/src/wp-includes/global-styles-and-settings.php
@@ -292,7 +292,9 @@ function wp_theme_has_theme_json() {
 	 * @see https://developer.wordpress.org/reference/functions/wp_cache_get/
 	 *
 	 * Ignore cache when `WP_DEBUG` is enabled, so it doesn't interfere with the theme
-	 * developers workflow.
+	 * developer's workflow.
+	 *
+	 * TODO Replace `WP_DEBUG` once an "in development mode" check is available in Core.
 	 */
 	if ( ! WP_DEBUG && is_int( $theme_has_support ) ) {
 		return (bool) $theme_has_support;

From c4a20376f3c8146a5273fba3e6105d054bc3b426 Mon Sep 17 00:00:00 2001
From: hellofromtonya <tonya.mork@automattic.com>
Date: Tue, 17 Jan 2023 14:55:43 -0600
Subject: [PATCH 14/15] Use todo annotation

---
 src/wp-includes/global-styles-and-settings.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/wp-includes/global-styles-and-settings.php b/src/wp-includes/global-styles-and-settings.php
index 14a11ff578646..be9b15dab6074 100644
--- a/src/wp-includes/global-styles-and-settings.php
+++ b/src/wp-includes/global-styles-and-settings.php
@@ -294,7 +294,7 @@ function wp_theme_has_theme_json() {
 	 * Ignore cache when `WP_DEBUG` is enabled, so it doesn't interfere with the theme
 	 * developer's workflow.
 	 *
-	 * TODO Replace `WP_DEBUG` once an "in development mode" check is available in Core.
+	 * @todo Replace `WP_DEBUG` once an "in development mode" check is available in Core.
 	 */
 	if ( ! WP_DEBUG && is_int( $theme_has_support ) ) {
 		return (bool) $theme_has_support;

From 3a5b3a13591e7e8f141d88f0752de91c0192096d Mon Sep 17 00:00:00 2001
From: hellofromtonya <tonya.mork@automattic.com>
Date: Wed, 18 Jan 2023 04:01:38 -0600
Subject: [PATCH 15/15] Rename wp_clean_theme_json_caches

---
 src/wp-includes/default-filters.php                    |  4 ++--
 src/wp-includes/global-styles-and-settings.php         |  2 +-
 tests/phpunit/tests/theme/wpThemeJsonResolver.php      | 10 +++++-----
 .../tests/webfonts/wpThemeJsonWebfontsHandler.php      |  2 +-
 4 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/src/wp-includes/default-filters.php b/src/wp-includes/default-filters.php
index bfb146c5a9424..4e6340700cc15 100644
--- a/src/wp-includes/default-filters.php
+++ b/src/wp-includes/default-filters.php
@@ -346,8 +346,8 @@
 add_action( 'init', '_register_core_block_patterns_and_categories' );
 add_action( 'init', 'check_theme_switched', 99 );
 add_action( 'init', array( 'WP_Block_Supports', 'init' ), 22 );
-add_action( 'switch_theme', 'wp_clean_theme_json_caches' );
-add_action( 'start_previewing_theme', 'wp_clean_theme_json_caches' );
+add_action( 'switch_theme', 'wp_clean_theme_json_cache' );
+add_action( 'start_previewing_theme', 'wp_clean_theme_json_cache' );
 add_action( 'after_switch_theme', '_wp_menus_changed' );
 add_action( 'after_switch_theme', '_wp_sidebars_changed' );
 add_action( 'wp_print_styles', 'print_emoji_styles' );
diff --git a/src/wp-includes/global-styles-and-settings.php b/src/wp-includes/global-styles-and-settings.php
index be9b15dab6074..d93792668752e 100644
--- a/src/wp-includes/global-styles-and-settings.php
+++ b/src/wp-includes/global-styles-and-settings.php
@@ -320,7 +320,7 @@ function wp_theme_has_theme_json() {
  *
  * @since 6.2.0
  */
-function wp_clean_theme_json_caches() {
+function wp_clean_theme_json_cache() {
 	wp_cache_delete( 'wp_theme_has_theme_json', 'theme_json' );
 	WP_Theme_JSON_Resolver::clean_cached_data();
 }
diff --git a/tests/phpunit/tests/theme/wpThemeJsonResolver.php b/tests/phpunit/tests/theme/wpThemeJsonResolver.php
index 9dd72ee929c50..a25de5e3b4b8b 100644
--- a/tests/phpunit/tests/theme/wpThemeJsonResolver.php
+++ b/tests/phpunit/tests/theme/wpThemeJsonResolver.php
@@ -110,7 +110,7 @@ public function tear_down() {
 		unset( $GLOBALS['wp_themes'] );
 
 		// Reset data between tests.
-		wp_clean_theme_json_caches();
+		wp_clean_theme_json_cache();
 		parent::tear_down();
 	}
 
@@ -376,7 +376,7 @@ public function data_has_same_registered_blocks_when_all_blocks_are_cached() {
 	 * @ticket 56467
 	 */
 	public function test_get_core_data( $should_fire_filter, $core_is_cached, $blocks_are_cached ) {
-		wp_clean_theme_json_caches();
+		wp_clean_theme_json_cache();
 
 		// If should cache core, then fire the method to cache it before running the tests.
 		if ( $core_is_cached ) {
@@ -621,7 +621,7 @@ function( $query ) use ( &$global_styles_query_count ) {
 		);
 		for ( $i = 0; $i < 3; $i++ ) {
 			WP_Theme_JSON_Resolver::get_user_data_from_wp_global_styles( $theme );
-			wp_clean_theme_json_caches();
+			wp_clean_theme_json_cache();
 		}
 		$this->assertSame( 0, $global_styles_query_count, 'Unexpected SQL queries detected for the wp_global_style post type prior to creation.' );
 
@@ -634,7 +634,7 @@ function( $query ) use ( &$global_styles_query_count ) {
 		$global_styles_query_count = 0;
 		for ( $i = 0; $i < 3; $i++ ) {
 			$new_user_cpt = WP_Theme_JSON_Resolver::get_user_data_from_wp_global_styles( $theme );
-			wp_clean_theme_json_caches();
+			wp_clean_theme_json_cache();
 			$this->assertSameSets( $user_cpt, $new_user_cpt, "User CPTs do not match on run {$i}." );
 		}
 		$this->assertSame( 1, $global_styles_query_count, 'Unexpected SQL queries detected for the wp_global_style post type after creation.' );
@@ -651,7 +651,7 @@ public function test_get_user_data_from_wp_global_styles_does_not_use_uncached_q
 		$query_count = get_num_queries();
 		for ( $i = 0; $i < 3; $i++ ) {
 			WP_Theme_JSON_Resolver::get_user_data_from_wp_global_styles( $theme );
-			wp_clean_theme_json_caches();
+			wp_clean_theme_json_cache();
 		}
 		$query_count = get_num_queries() - $query_count;
 		$this->assertSame( 0, $query_count, 'Unexpected SQL queries detected for the wp_global_style post type prior to creation.' );
diff --git a/tests/phpunit/tests/webfonts/wpThemeJsonWebfontsHandler.php b/tests/phpunit/tests/webfonts/wpThemeJsonWebfontsHandler.php
index be8709cb71f22..ae7deacc01977 100644
--- a/tests/phpunit/tests/webfonts/wpThemeJsonWebfontsHandler.php
+++ b/tests/phpunit/tests/webfonts/wpThemeJsonWebfontsHandler.php
@@ -129,7 +129,7 @@ public function data_font_face_not_generated() {
 	private function setup_theme_and_test( $theme_name ) {
 		switch_theme( $theme_name );
 		do_action( 'after_setup_theme' );
-		wp_clean_theme_json_caches();
+		wp_clean_theme_json_cache();
 		do_action( 'wp_loaded' );
 		do_action( 'wp_enqueue_scripts' );
 	}