From 4ca1d9bc9017f42aa84080148ff0222a9418d3b2 Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Thu, 7 Jul 2022 10:48:36 +0300
Subject: [PATCH 01/17] Add a CSS_Rule object

---
 lib/load.php                                  |   3 +
 .../class-wp-style-engine-css-rule.php        | 107 ++++++++++++++++++
 tools/webpack/packages.js                     |   1 +
 3 files changed, 111 insertions(+)
 create mode 100644 packages/style-engine/class-wp-style-engine-css-rule.php

diff --git a/lib/load.php b/lib/load.php
index b125ef04913a62..7c68df0a9803a5 100644
--- a/lib/load.php
+++ b/lib/load.php
@@ -116,7 +116,10 @@ function gutenberg_is_experiment_enabled( $name ) {
 if ( file_exists( __DIR__ . '/../build/style-engine/class-wp-style-engine-css-declarations-gutenberg.php' ) ) {
 	require_once __DIR__ . '/../build/style-engine/class-wp-style-engine-css-declarations-gutenberg.php';
 }
+if ( file_exists( __DIR__ . '/../build/style-engine/class-wp-style-engine-css-rule-gutenberg.php' ) ) {
+	require_once __DIR__ . '/../build/style-engine/class-wp-style-engine-css-rule-gutenberg.php';
 
+}
 // Block supports overrides.
 require __DIR__ . '/block-supports/utils.php';
 require __DIR__ . '/block-supports/elements.php';
diff --git a/packages/style-engine/class-wp-style-engine-css-rule.php b/packages/style-engine/class-wp-style-engine-css-rule.php
new file mode 100644
index 00000000000000..70195382458468
--- /dev/null
+++ b/packages/style-engine/class-wp-style-engine-css-rule.php
@@ -0,0 +1,107 @@
+<?php
+/**
+ * WP_Style_Engine_CSS_Rule
+ *
+ * An object for CSS rules.
+ *
+ * @package Gutenberg
+ */
+
+if ( class_exists( 'WP_Style_Engine_CSS_Rule' ) ) {
+	return;
+}
+
+/**
+ * Holds, sanitizes, processes and prints CSS declarations for the style engine.
+ *
+ * @access private
+ */
+class WP_Style_Engine_CSS_Rule {
+
+	/**
+	 * The selector.
+	 *
+	 * @var string
+	 */
+	protected $selector;
+
+	/**
+	 * The parent rule.
+	 *
+	 * @var WP_Style_Engine_CSS_Rule
+	 */
+	protected $parent;
+
+	/**
+	 * The selector declarations.
+	 *
+	 * Contains an array of WP_Style_Engine_CSS_Declarations objects.
+	 *
+	 * @var WP_Style_Engine_CSS_Declarations[]
+	 */
+	protected $declarations = array();
+
+	/**
+	 * Constructor
+	 *
+	 * @param string                             $selector     The CSS selector.
+	 * @param WP_Style_Engine_CSS_Rule|null      $parent       The parent rule.
+	 * @param WP_Style_Engine_CSS_Declarations[] $declarations An array of WP_Style_Engine_CSS_Declarations objects.
+	 */
+	public function __construct( $selector = '', $parent = null, $declarations = array() ) {
+		$this->set_selector( $selector );
+		$this->set_parent( $parent );
+		$this->set_declarations( $declarations );
+	}
+
+	/**
+	 * Set the selector.
+	 *
+	 * @param string $selector The CSS selector.
+	 */
+	public function set_selector( $selector ) {
+		$this->selector = $selector;
+	}
+
+	/**
+	 * Set the parent selector.
+	 *
+	 * @param WP_Style_Engine_CSS_Rule $parent The parent rule.
+	 */
+	public function set_parent( $parent ) {
+		$this->parent = $parent;
+	}
+
+	/**
+	 * Set the declarations.
+	 *
+	 * @param WP_Style_Engine_CSS_Declarations[] $declarations An array of WP_Style_Engine_CSS_Declarations objects.
+	 */
+	public function set_declarations( $declarations ) {
+		if ( $declarations instanceof WP_Style_Engine_CSS_Declarations ) {
+			$declarations = array( $declarations );
+		}
+		$this->declarations = array_merge( $this->$declarations, $declarations );
+	}
+
+	/**
+	 * Get the parent selector.
+	 *
+	 * @return string
+	 */
+	public function get_parent_selector() {
+		return $this->parent ? $this->parent->get_selector() : '';
+	}
+
+	/**
+	 * Get the full selector.
+	 *
+	 * @return string
+	 */
+	public function get_selector() {
+		if ( 0 === strpos( $this->selector, '&' ) ) {
+			return $this->get_parent_selector() . substr( $this->selector, 1 );
+		}
+		return $this->get_parent_selector() . ' ' . $this->selector;
+	}
+}
diff --git a/tools/webpack/packages.js b/tools/webpack/packages.js
index c13ceea5de9ecc..978333f880d43a 100644
--- a/tools/webpack/packages.js
+++ b/tools/webpack/packages.js
@@ -37,6 +37,7 @@ const bundledPackagesPhpConfig = [
 		to: 'build/style-engine/',
 		replaceClasses: [
 			'WP_Style_Engine_CSS_Declarations',
+			'WP_Style_Engine_CSS_Rule',
 			'WP_Style_Engine',
 		],
 	},

From df1528110232fb6dec9e60b065d4a1f796c00b2f Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Thu, 7 Jul 2022 11:26:35 +0300
Subject: [PATCH 02/17] Add a rules store

---
 lib/load.php                                  |   5 +-
 .../class-wp-style-engine-css-rules-store.php | 138 ++++++++++++++++++
 tools/webpack/packages.js                     |   1 +
 3 files changed, 143 insertions(+), 1 deletion(-)
 create mode 100644 packages/style-engine/class-wp-style-engine-css-rules-store.php

diff --git a/lib/load.php b/lib/load.php
index 7c68df0a9803a5..57f7993440f57a 100644
--- a/lib/load.php
+++ b/lib/load.php
@@ -118,8 +118,11 @@ function gutenberg_is_experiment_enabled( $name ) {
 }
 if ( file_exists( __DIR__ . '/../build/style-engine/class-wp-style-engine-css-rule-gutenberg.php' ) ) {
 	require_once __DIR__ . '/../build/style-engine/class-wp-style-engine-css-rule-gutenberg.php';
-
 }
+if ( file_exists( __DIR__ . '/../build/style-engine/class-wp-style-engine-css-rules-store-gutenberg.php' ) ) {
+	require_once __DIR__ . '/../build/style-engine/class-wp-style-engine-css-rules-store-gutenberg.php';
+}
+
 // Block supports overrides.
 require __DIR__ . '/block-supports/utils.php';
 require __DIR__ . '/block-supports/elements.php';
diff --git a/packages/style-engine/class-wp-style-engine-css-rules-store.php b/packages/style-engine/class-wp-style-engine-css-rules-store.php
new file mode 100644
index 00000000000000..acdd3a560bfa13
--- /dev/null
+++ b/packages/style-engine/class-wp-style-engine-css-rules-store.php
@@ -0,0 +1,138 @@
+<?php
+/**
+ * WP_Style_Engine_CSS_Rules_Store
+ *
+ * A store for WP_Style_Engine_CSS_Rule objects.
+ *
+ * @package Gutenberg
+ */
+
+if ( class_exists( 'WP_Style_Engine_CSS_Rules_Store' ) ) {
+	return;
+}
+
+/**
+ * Holds, sanitizes, processes and prints CSS declarations for the style engine.
+ *
+ * @access private
+ */
+class WP_Style_Engine_CSS_Rules_Store {
+
+	/**
+	 * An array of CSS Rules objects.
+	 *
+	 * @static
+	 *
+	 * @var WP_Style_Engine_CSS_Rule[]
+	 */
+	protected static $rules = array();
+
+	/**
+	 * Get an array of all rules.
+	 *
+	 * @static
+	 *
+	 * @return WP_Style_Engine_CSS_Rule[]
+	 */
+	public static function get_all_rules() {
+		return static::$rules;
+	}
+
+	/**
+	 * Get a WP_Style_Engine_CSS_Rule object by its selector.
+	 *
+	 * @static
+	 *
+	 * @param string $selector The CSS selector.
+	 */
+	public static function get_rule( $selector ) {
+		if ( empty( $selector ) ) {
+			return;
+		}
+
+		$selector_parts = static::deconstruct_selector( $selector );
+		$full_selector  = '';
+		foreach ( $selector_parts as $key => $selector_part ) {
+			// Get the parent object if needed.
+			$parent = 0 === $key ? null : static::get_rule( $selector_parts[ $full_selector ] );
+			// Compile the full selector for the store.
+			$full_selector .= ( 0 === strpos( $selector_part, '&' ) ) ? substr( $selector_part, 1 ) : ' ' . $selector_part;
+			if ( 0 === $key ) {
+				$full_selector = ltrim( $full_selector );
+			}
+			// Create the rule if it doesn't exist.
+			if ( empty( static::$rules[ $full_selector ] ) ) {
+				static::$rules[ $full_selector ] = new WP_Style_Engine_CSS_Rule( $selector_part, $parent );
+			}
+		}
+
+		return static::$rules[ $selector ];
+	}
+
+	/**
+	 * Deconstruct a selector to its parts.
+	 *
+	 * @static
+	 *
+	 * @param string $selector The CSS selector.
+	 *
+	 * @return array An array of selector parts.
+	 */
+	public static function deconstruct_selector( $selector ) {
+		$selector = trim( $selector );
+
+		// Split selector parts on space characters.
+		$parts = explode( ' ', $selector );
+		$parts = array_map( 'trim', $parts );
+
+		// Remove empty parts.
+		$parts = array_filter( $parts );
+
+		// Split parts on ':' characters.
+		$parts = static::deconstruct_selector_array_on_character( $parts, ':' );
+
+		return $parts;
+	}
+
+	/**
+	 * Expands and re-structures an array based on a character.
+	 *
+	 * @static
+	 *
+	 * @param array  $array The array to expand.
+	 * @param string $character The character to expand on.
+	 *
+	 * @return array The expanded array.
+	 */
+	public static function deconstruct_selector_array_on_character( $array, $character ) {
+		$new_array = array();
+		foreach ( $array as $value ) {
+			if ( strpos( $value, $character ) === false ) {
+				$new_array[] = $value;
+				continue;
+			}
+
+			$value = str_replace( $character, "SPLIT_CHARACTER$character", $value );
+			if ( ':' === $character ) {
+				$value = str_replace( ':', '&:', $value );
+			}
+			$value     = explode( 'SPLIT_CHARACTER', $value );
+			$new_array = array_merge( $new_array, $value );
+		}
+		return $new_array;
+	}
+
+	/**
+	 * Inject an array inside an array at a specific index.
+	 *
+	 * @static
+	 *
+	 * @param array $array The array to inject into.
+	 * @param array $inject The array to inject.
+	 * @param int   $index The index to inject at.
+	 */
+	public static function inject_array_at_index( $array, $inject, $index ) {
+		$array = array_slice( $array, 0, $index, true ) + $inject + array_slice( $array, $index, count( $array ) - $index, true );
+		return $array;
+	}
+}
diff --git a/tools/webpack/packages.js b/tools/webpack/packages.js
index 978333f880d43a..2f6720d579452f 100644
--- a/tools/webpack/packages.js
+++ b/tools/webpack/packages.js
@@ -37,6 +37,7 @@ const bundledPackagesPhpConfig = [
 		to: 'build/style-engine/',
 		replaceClasses: [
 			'WP_Style_Engine_CSS_Declarations',
+			'WP_Style_Engine_CSS_Rules_Store',
 			'WP_Style_Engine_CSS_Rule',
 			'WP_Style_Engine',
 		],

From da2c4338bf3a95f23035e70bf59c4ee2347844c7 Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Thu, 7 Jul 2022 11:56:03 +0300
Subject: [PATCH 03/17] some inline docs & cleanup on the store

---
 .../class-wp-style-engine-css-rules-store.php | 28 +++++++++----------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/packages/style-engine/class-wp-style-engine-css-rules-store.php b/packages/style-engine/class-wp-style-engine-css-rules-store.php
index acdd3a560bfa13..8efe50eb9a70ee 100644
--- a/packages/style-engine/class-wp-style-engine-css-rules-store.php
+++ b/packages/style-engine/class-wp-style-engine-css-rules-store.php
@@ -46,10 +46,20 @@ public static function get_all_rules() {
 	 * @param string $selector The CSS selector.
 	 */
 	public static function get_rule( $selector ) {
+
+		// Bail early if there is no selector.
 		if ( empty( $selector ) ) {
 			return;
 		}
 
+		// If the selector is already stored, return it.
+		if ( isset( static::$rules[ $selector ] ) ) {
+			return static::$rules[ $selector ];
+		}
+
+		// Create the selector if it doesn't exist.
+		// To do that, first deconstruct the selector to its parts
+		// and build the hierarchy of selector objects prior to storing it.
 		$selector_parts = static::deconstruct_selector( $selector );
 		$full_selector  = '';
 		foreach ( $selector_parts as $key => $selector_part ) {
@@ -112,27 +122,17 @@ public static function deconstruct_selector_array_on_character( $array, $charact
 				continue;
 			}
 
+			// Use "SPLIT_CHARACTER" as a delimiter.
 			$value = str_replace( $character, "SPLIT_CHARACTER$character", $value );
+
+			// Pseudo-selectors are a special case.
 			if ( ':' === $character ) {
 				$value = str_replace( ':', '&:', $value );
 			}
+
 			$value     = explode( 'SPLIT_CHARACTER', $value );
 			$new_array = array_merge( $new_array, $value );
 		}
 		return $new_array;
 	}
-
-	/**
-	 * Inject an array inside an array at a specific index.
-	 *
-	 * @static
-	 *
-	 * @param array $array The array to inject into.
-	 * @param array $inject The array to inject.
-	 * @param int   $index The index to inject at.
-	 */
-	public static function inject_array_at_index( $array, $inject, $index ) {
-		$array = array_slice( $array, 0, $index, true ) + $inject + array_slice( $array, $index, count( $array ) - $index, true );
-		return $array;
-	}
 }

From f6176f710fd864df89f4371a5defc7946078b9d7 Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Thu, 7 Jul 2022 13:03:26 +0300
Subject: [PATCH 04/17] typos & fixes

---
 .../class-wp-style-engine-css-rule.php        | 22 ++++++++++++++++++-
 .../class-wp-style-engine-css-rules-store.php |  4 +++-
 2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/packages/style-engine/class-wp-style-engine-css-rule.php b/packages/style-engine/class-wp-style-engine-css-rule.php
index 70195382458468..106507e8ecce3f 100644
--- a/packages/style-engine/class-wp-style-engine-css-rule.php
+++ b/packages/style-engine/class-wp-style-engine-css-rule.php
@@ -60,6 +60,9 @@ public function __construct( $selector = '', $parent = null, $declarations = arr
 	 * @param string $selector The CSS selector.
 	 */
 	public function set_selector( $selector ) {
+		if ( empty( $selector ) ) {
+			return;
+		}
 		$this->selector = $selector;
 	}
 
@@ -69,6 +72,9 @@ public function set_selector( $selector ) {
 	 * @param WP_Style_Engine_CSS_Rule $parent The parent rule.
 	 */
 	public function set_parent( $parent ) {
+		if ( ! $parent instanceof WP_Style_Engine_CSS_Rule ) {
+			return;
+		}
 		$this->parent = $parent;
 	}
 
@@ -81,7 +87,7 @@ public function set_declarations( $declarations ) {
 		if ( $declarations instanceof WP_Style_Engine_CSS_Declarations ) {
 			$declarations = array( $declarations );
 		}
-		$this->declarations = array_merge( $this->$declarations, $declarations );
+		$this->declarations = array_merge( $this->declarations, $declarations );
 	}
 
 	/**
@@ -104,4 +110,18 @@ public function get_selector() {
 		}
 		return $this->get_parent_selector() . ' ' . $this->selector;
 	}
+
+	/**
+	 * Get the CSS.
+	 *
+	 * @return string
+	 */
+	public function get_css() {
+		$css = $this->get_selector() . ' {';
+		foreach ( $this->declarations as $declaration ) {
+			$css .= $declaration->get_declarations_string();
+		}
+		$css .= '}';
+		return $css;
+	}
 }
diff --git a/packages/style-engine/class-wp-style-engine-css-rules-store.php b/packages/style-engine/class-wp-style-engine-css-rules-store.php
index 8efe50eb9a70ee..31f6603c7ddfcb 100644
--- a/packages/style-engine/class-wp-style-engine-css-rules-store.php
+++ b/packages/style-engine/class-wp-style-engine-css-rules-store.php
@@ -47,6 +47,8 @@ public static function get_all_rules() {
 	 */
 	public static function get_rule( $selector ) {
 
+		$selector = trim( $selector );
+
 		// Bail early if there is no selector.
 		if ( empty( $selector ) ) {
 			return;
@@ -64,7 +66,7 @@ public static function get_rule( $selector ) {
 		$full_selector  = '';
 		foreach ( $selector_parts as $key => $selector_part ) {
 			// Get the parent object if needed.
-			$parent = 0 === $key ? null : static::get_rule( $selector_parts[ $full_selector ] );
+			$parent = 0 === $key ? null : static::get_rule( $full_selector );
 			// Compile the full selector for the store.
 			$full_selector .= ( 0 === strpos( $selector_part, '&' ) ) ? substr( $selector_part, 1 ) : ' ' . $selector_part;
 			if ( 0 === $key ) {

From 0a6b4ef50308785eeab8ac887f3c0dc641710c87 Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Wed, 13 Jul 2022 11:10:49 +0300
Subject: [PATCH 05/17] remove parent relations for rules

---
 .../class-wp-style-engine-css-rule.php        | 37 +--------
 .../class-wp-style-engine-css-rules-store.php | 82 +------------------
 2 files changed, 5 insertions(+), 114 deletions(-)

diff --git a/packages/style-engine/class-wp-style-engine-css-rule.php b/packages/style-engine/class-wp-style-engine-css-rule.php
index 106507e8ecce3f..53eb4594188f52 100644
--- a/packages/style-engine/class-wp-style-engine-css-rule.php
+++ b/packages/style-engine/class-wp-style-engine-css-rule.php
@@ -25,13 +25,6 @@ class WP_Style_Engine_CSS_Rule {
 	 */
 	protected $selector;
 
-	/**
-	 * The parent rule.
-	 *
-	 * @var WP_Style_Engine_CSS_Rule
-	 */
-	protected $parent;
-
 	/**
 	 * The selector declarations.
 	 *
@@ -45,12 +38,10 @@ class WP_Style_Engine_CSS_Rule {
 	 * Constructor
 	 *
 	 * @param string                             $selector     The CSS selector.
-	 * @param WP_Style_Engine_CSS_Rule|null      $parent       The parent rule.
 	 * @param WP_Style_Engine_CSS_Declarations[] $declarations An array of WP_Style_Engine_CSS_Declarations objects.
 	 */
-	public function __construct( $selector = '', $parent = null, $declarations = array() ) {
+	public function __construct( $selector = '', $declarations = array() ) {
 		$this->set_selector( $selector );
-		$this->set_parent( $parent );
 		$this->set_declarations( $declarations );
 	}
 
@@ -66,18 +57,6 @@ public function set_selector( $selector ) {
 		$this->selector = $selector;
 	}
 
-	/**
-	 * Set the parent selector.
-	 *
-	 * @param WP_Style_Engine_CSS_Rule $parent The parent rule.
-	 */
-	public function set_parent( $parent ) {
-		if ( ! $parent instanceof WP_Style_Engine_CSS_Rule ) {
-			return;
-		}
-		$this->parent = $parent;
-	}
-
 	/**
 	 * Set the declarations.
 	 *
@@ -90,25 +69,13 @@ public function set_declarations( $declarations ) {
 		$this->declarations = array_merge( $this->declarations, $declarations );
 	}
 
-	/**
-	 * Get the parent selector.
-	 *
-	 * @return string
-	 */
-	public function get_parent_selector() {
-		return $this->parent ? $this->parent->get_selector() : '';
-	}
-
 	/**
 	 * Get the full selector.
 	 *
 	 * @return string
 	 */
 	public function get_selector() {
-		if ( 0 === strpos( $this->selector, '&' ) ) {
-			return $this->get_parent_selector() . substr( $this->selector, 1 );
-		}
-		return $this->get_parent_selector() . ' ' . $this->selector;
+		return $this->selector;
 	}
 
 	/**
diff --git a/packages/style-engine/class-wp-style-engine-css-rules-store.php b/packages/style-engine/class-wp-style-engine-css-rules-store.php
index 31f6603c7ddfcb..d0a8b1a18873c9 100644
--- a/packages/style-engine/class-wp-style-engine-css-rules-store.php
+++ b/packages/style-engine/class-wp-style-engine-css-rules-store.php
@@ -54,87 +54,11 @@ public static function get_rule( $selector ) {
 			return;
 		}
 
-		// If the selector is already stored, return it.
-		if ( isset( static::$rules[ $selector ] ) ) {
-			return static::$rules[ $selector ];
-		}
-
-		// Create the selector if it doesn't exist.
-		// To do that, first deconstruct the selector to its parts
-		// and build the hierarchy of selector objects prior to storing it.
-		$selector_parts = static::deconstruct_selector( $selector );
-		$full_selector  = '';
-		foreach ( $selector_parts as $key => $selector_part ) {
-			// Get the parent object if needed.
-			$parent = 0 === $key ? null : static::get_rule( $full_selector );
-			// Compile the full selector for the store.
-			$full_selector .= ( 0 === strpos( $selector_part, '&' ) ) ? substr( $selector_part, 1 ) : ' ' . $selector_part;
-			if ( 0 === $key ) {
-				$full_selector = ltrim( $full_selector );
-			}
-			// Create the rule if it doesn't exist.
-			if ( empty( static::$rules[ $full_selector ] ) ) {
-				static::$rules[ $full_selector ] = new WP_Style_Engine_CSS_Rule( $selector_part, $parent );
-			}
+		// Create the rule if it doesn't exist.
+		if ( empty( static::$rules[ $selector ] ) ) {
+			static::$rules[ $selector ] = new WP_Style_Engine_CSS_Rule( $selector );
 		}
 
 		return static::$rules[ $selector ];
 	}
-
-	/**
-	 * Deconstruct a selector to its parts.
-	 *
-	 * @static
-	 *
-	 * @param string $selector The CSS selector.
-	 *
-	 * @return array An array of selector parts.
-	 */
-	public static function deconstruct_selector( $selector ) {
-		$selector = trim( $selector );
-
-		// Split selector parts on space characters.
-		$parts = explode( ' ', $selector );
-		$parts = array_map( 'trim', $parts );
-
-		// Remove empty parts.
-		$parts = array_filter( $parts );
-
-		// Split parts on ':' characters.
-		$parts = static::deconstruct_selector_array_on_character( $parts, ':' );
-
-		return $parts;
-	}
-
-	/**
-	 * Expands and re-structures an array based on a character.
-	 *
-	 * @static
-	 *
-	 * @param array  $array The array to expand.
-	 * @param string $character The character to expand on.
-	 *
-	 * @return array The expanded array.
-	 */
-	public static function deconstruct_selector_array_on_character( $array, $character ) {
-		$new_array = array();
-		foreach ( $array as $value ) {
-			if ( strpos( $value, $character ) === false ) {
-				$new_array[] = $value;
-				continue;
-			}
-
-			// Use "SPLIT_CHARACTER" as a delimiter.
-			$value = str_replace( $character, "SPLIT_CHARACTER$character", $value );
-
-			// Pseudo-selectors are a special case.
-			if ( ':' === $character ) {
-				$value = str_replace( ':', '&:', $value );
-			}
-
-			$value     = explode( 'SPLIT_CHARACTER', $value );
-			$new_array = array_merge( $new_array, $value );
-		}
-		return $new_array;
-	}
 }

From 7c48c5ef28be2283b25480eaeac714d5dad26e3a Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Wed, 13 Jul 2022 11:13:01 +0300
Subject: [PATCH 06/17] escape the selector

---
 packages/style-engine/class-wp-style-engine-css-rule.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/style-engine/class-wp-style-engine-css-rule.php b/packages/style-engine/class-wp-style-engine-css-rule.php
index 53eb4594188f52..902e7ac6a8dc3b 100644
--- a/packages/style-engine/class-wp-style-engine-css-rule.php
+++ b/packages/style-engine/class-wp-style-engine-css-rule.php
@@ -54,7 +54,7 @@ public function set_selector( $selector ) {
 		if ( empty( $selector ) ) {
 			return;
 		}
-		$this->selector = $selector;
+		$this->selector = esc_html( $selector );
 	}
 
 	/**

From ca30f7e7811d3e0593f43cb34d45852a5d8d59f6 Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Wed, 13 Jul 2022 11:29:45 +0300
Subject: [PATCH 07/17] Allow for multiple named instances of the store

---
 .../class-wp-style-engine-css-rules-store.php | 40 +++++++++++++------
 1 file changed, 28 insertions(+), 12 deletions(-)

diff --git a/packages/style-engine/class-wp-style-engine-css-rules-store.php b/packages/style-engine/class-wp-style-engine-css-rules-store.php
index d0a8b1a18873c9..3ac4ef4648d787 100644
--- a/packages/style-engine/class-wp-style-engine-css-rules-store.php
+++ b/packages/style-engine/class-wp-style-engine-css-rules-store.php
@@ -19,33 +19,49 @@
 class WP_Style_Engine_CSS_Rules_Store {
 
 	/**
-	 * An array of CSS Rules objects.
+	 * An array of named WP_Style_Engine_CSS_Rules_Store objects.
 	 *
 	 * @static
 	 *
+	 * @var WP_Style_Engine_CSS_Rules_Store[]
+	 */
+	protected static $stores = array();
+
+	/**
+	 * An array of CSS Rules objects assigned to the store.
+	 *
 	 * @var WP_Style_Engine_CSS_Rule[]
 	 */
-	protected static $rules = array();
+	protected $rules = array();
 
 	/**
-	 * Get an array of all rules.
+	 * Get an instance of the store.
 	 *
-	 * @static
+	 * @param string $store_name The name of the store.
+	 *
+	 * @return WP_Style_Engine_CSS_Rules_Store
+	 */
+	public static function get_store( $store_name ) {
+		if ( ! isset( static::$stores[ $store_name ] ) ) {
+			static::$stores[ $store_name ] = new WP_Style_Engine_CSS_Rules_Store( $store_name );
+		}
+		return static::$stores[ $store_name ];
+	}
+	/**
+	 * Get an array of all rules.
 	 *
 	 * @return WP_Style_Engine_CSS_Rule[]
 	 */
-	public static function get_all_rules() {
-		return static::$rules;
+	public function get_all_rules() {
+		return $this->rules;
 	}
 
 	/**
 	 * Get a WP_Style_Engine_CSS_Rule object by its selector.
 	 *
-	 * @static
-	 *
 	 * @param string $selector The CSS selector.
 	 */
-	public static function get_rule( $selector ) {
+	public function get_rule( $selector ) {
 
 		$selector = trim( $selector );
 
@@ -55,10 +71,10 @@ public static function get_rule( $selector ) {
 		}
 
 		// Create the rule if it doesn't exist.
-		if ( empty( static::$rules[ $selector ] ) ) {
-			static::$rules[ $selector ] = new WP_Style_Engine_CSS_Rule( $selector );
+		if ( empty( $this->rules[ $selector ] ) ) {
+			$this->rules[ $selector ] = new WP_Style_Engine_CSS_Rule( $selector );
 		}
 
-		return static::$rules[ $selector ];
+		return $this->rules[ $selector ];
 	}
 }

From 9de86d72129e636e08d46f76f3faf0a805968742 Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Thu, 14 Jul 2022 10:18:15 +0300
Subject: [PATCH 08/17] Use a single declarations object per rule

---
 .../class-wp-style-engine-css-rule.php        | 41 ++++++++++++-------
 1 file changed, 26 insertions(+), 15 deletions(-)

diff --git a/packages/style-engine/class-wp-style-engine-css-rule.php b/packages/style-engine/class-wp-style-engine-css-rule.php
index 902e7ac6a8dc3b..ad3a245df75654 100644
--- a/packages/style-engine/class-wp-style-engine-css-rule.php
+++ b/packages/style-engine/class-wp-style-engine-css-rule.php
@@ -28,17 +28,18 @@ class WP_Style_Engine_CSS_Rule {
 	/**
 	 * The selector declarations.
 	 *
-	 * Contains an array of WP_Style_Engine_CSS_Declarations objects.
+	 * Contains a WP_Style_Engine_CSS_Declarations object.
 	 *
-	 * @var WP_Style_Engine_CSS_Declarations[]
+	 * @var WP_Style_Engine_CSS_Declarations
 	 */
-	protected $declarations = array();
+	protected $declarations;
 
 	/**
 	 * Constructor
 	 *
-	 * @param string                             $selector     The CSS selector.
-	 * @param WP_Style_Engine_CSS_Declarations[] $declarations An array of WP_Style_Engine_CSS_Declarations objects.
+	 * @param string                                 $selector     The CSS selector.
+	 * @param array|WP_Style_Engine_CSS_Declarations $declarations An array of declarations (property => value pairs),
+	 *                                                             or a WP_Style_Engine_CSS_Declarations object.
 	 */
 	public function __construct( $selector = '', $declarations = array() ) {
 		$this->set_selector( $selector );
@@ -60,13 +61,28 @@ public function set_selector( $selector ) {
 	/**
 	 * Set the declarations.
 	 *
-	 * @param WP_Style_Engine_CSS_Declarations[] $declarations An array of WP_Style_Engine_CSS_Declarations objects.
+	 * @param array|WP_Style_Engine_CSS_Declarations $declarations An array of declarations (property => value pairs),
+	 *                                                             or a WP_Style_Engine_CSS_Declarations object.
 	 */
 	public function set_declarations( $declarations ) {
-		if ( $declarations instanceof WP_Style_Engine_CSS_Declarations ) {
-			$declarations = array( $declarations );
+		$is_declarations_object = ! is_array( $declarations );
+		$declarations_array     = $is_declarations_object ? $declarations->get_declarations() : $declarations;
+
+		if ( null === $this->declarations && $is_declarations_object ) {
+			$this->declarations = $declarations;
+		} elseif ( null === $this->declarations ) {
+			$this->declarations = new WP_Style_Engine_CSS_Declarations( $declarations_array );
 		}
-		$this->declarations = array_merge( $this->declarations, $declarations );
+		$this->declarations->add_declarations( $declarations_array );
+	}
+
+	/**
+	 * Get the declarations object.
+	 *
+	 * @return WP_Style_Engine_CSS_Declarations
+	 */
+	public function get_declarations() {
+		return $this->declarations;
 	}
 
 	/**
@@ -84,11 +100,6 @@ public function get_selector() {
 	 * @return string
 	 */
 	public function get_css() {
-		$css = $this->get_selector() . ' {';
-		foreach ( $this->declarations as $declaration ) {
-			$css .= $declaration->get_declarations_string();
-		}
-		$css .= '}';
-		return $css;
+		return $this->get_selector() . ' {' . $this->declarations->get_declarations_string() . '}';
 	}
 }

From 59dbf675612ed049c9d69d366f91527dd1b4307b Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Thu, 14 Jul 2022 10:20:25 +0300
Subject: [PATCH 09/17] Allow chaining methods

---
 packages/style-engine/class-wp-style-engine-css-rule.php | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/packages/style-engine/class-wp-style-engine-css-rule.php b/packages/style-engine/class-wp-style-engine-css-rule.php
index ad3a245df75654..93be7fceea2775 100644
--- a/packages/style-engine/class-wp-style-engine-css-rule.php
+++ b/packages/style-engine/class-wp-style-engine-css-rule.php
@@ -50,12 +50,16 @@ public function __construct( $selector = '', $declarations = array() ) {
 	 * Set the selector.
 	 *
 	 * @param string $selector The CSS selector.
+	 *
+	 * @return WP_Style_Engine_CSS_Rule Returns the object to allow chaining of methods.
 	 */
 	public function set_selector( $selector ) {
 		if ( empty( $selector ) ) {
 			return;
 		}
 		$this->selector = esc_html( $selector );
+
+		return $this;
 	}
 
 	/**
@@ -63,6 +67,8 @@ public function set_selector( $selector ) {
 	 *
 	 * @param array|WP_Style_Engine_CSS_Declarations $declarations An array of declarations (property => value pairs),
 	 *                                                             or a WP_Style_Engine_CSS_Declarations object.
+	 *
+	 * @return WP_Style_Engine_CSS_Rule Returns the object to allow chaining of methods.
 	 */
 	public function set_declarations( $declarations ) {
 		$is_declarations_object = ! is_array( $declarations );
@@ -74,6 +80,8 @@ public function set_declarations( $declarations ) {
 			$this->declarations = new WP_Style_Engine_CSS_Declarations( $declarations_array );
 		}
 		$this->declarations->add_declarations( $declarations_array );
+
+		return $this;
 	}
 
 	/**

From 94a141a6f54fc47bc974213dacde52cecdb38251 Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Thu, 14 Jul 2022 10:28:46 +0300
Subject: [PATCH 10/17] Remove esc_html

---
 packages/style-engine/class-wp-style-engine-css-rule.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/style-engine/class-wp-style-engine-css-rule.php b/packages/style-engine/class-wp-style-engine-css-rule.php
index 93be7fceea2775..e10c07183d21ae 100644
--- a/packages/style-engine/class-wp-style-engine-css-rule.php
+++ b/packages/style-engine/class-wp-style-engine-css-rule.php
@@ -57,7 +57,7 @@ public function set_selector( $selector ) {
 		if ( empty( $selector ) ) {
 			return;
 		}
-		$this->selector = esc_html( $selector );
+		$this->selector = $selector;
 
 		return $this;
 	}

From be06402b076fbcbf0fbc4aeb3cb9dc35b3df8cda Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Thu, 14 Jul 2022 13:12:54 +0300
Subject: [PATCH 11/17] Add a default value for store_name

---
 packages/style-engine/class-wp-style-engine-css-rules-store.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/style-engine/class-wp-style-engine-css-rules-store.php b/packages/style-engine/class-wp-style-engine-css-rules-store.php
index 3ac4ef4648d787..2d95fbaee161b2 100644
--- a/packages/style-engine/class-wp-style-engine-css-rules-store.php
+++ b/packages/style-engine/class-wp-style-engine-css-rules-store.php
@@ -41,7 +41,7 @@ class WP_Style_Engine_CSS_Rules_Store {
 	 *
 	 * @return WP_Style_Engine_CSS_Rules_Store
 	 */
-	public static function get_store( $store_name ) {
+	public static function get_store( $store_name = 'default' ) {
 		if ( ! isset( static::$stores[ $store_name ] ) ) {
 			static::$stores[ $store_name ] = new WP_Style_Engine_CSS_Rules_Store( $store_name );
 		}

From d4a21048f23ee37054710370fd12f7d8d29daa15 Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Thu, 14 Jul 2022 13:18:05 +0300
Subject: [PATCH 12/17] use static()

---
 packages/style-engine/class-wp-style-engine-css-rules-store.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/style-engine/class-wp-style-engine-css-rules-store.php b/packages/style-engine/class-wp-style-engine-css-rules-store.php
index 2d95fbaee161b2..bfc7fba9ecd71f 100644
--- a/packages/style-engine/class-wp-style-engine-css-rules-store.php
+++ b/packages/style-engine/class-wp-style-engine-css-rules-store.php
@@ -43,7 +43,7 @@ class WP_Style_Engine_CSS_Rules_Store {
 	 */
 	public static function get_store( $store_name = 'default' ) {
 		if ( ! isset( static::$stores[ $store_name ] ) ) {
-			static::$stores[ $store_name ] = new WP_Style_Engine_CSS_Rules_Store( $store_name );
+			static::$stores[ $store_name ] = new static( $store_name );
 		}
 		return static::$stores[ $store_name ];
 	}

From 4104e21d01d3056f341a18debde64736da645793 Mon Sep 17 00:00:00 2001
From: ramonjd <ramonjd@gmail.com>
Date: Fri, 15 Jul 2022 11:30:54 +1000
Subject: [PATCH 13/17] Adding tests

---
 .../class-wp-style-engine-css-rule-test.php   |  96 +++++++++++++++
 ...s-wp-style-engine-css-rules-store-test.php | 115 ++++++++++++++++++
 2 files changed, 211 insertions(+)
 create mode 100644 packages/style-engine/phpunit/class-wp-style-engine-css-rule-test.php
 create mode 100644 packages/style-engine/phpunit/class-wp-style-engine-css-rules-store-test.php

diff --git a/packages/style-engine/phpunit/class-wp-style-engine-css-rule-test.php b/packages/style-engine/phpunit/class-wp-style-engine-css-rule-test.php
new file mode 100644
index 00000000000000..9a42ade4acb16f
--- /dev/null
+++ b/packages/style-engine/phpunit/class-wp-style-engine-css-rule-test.php
@@ -0,0 +1,96 @@
+<?php
+/**
+ * Tests the Style Engine CSS Rule class.
+ *
+ * @package    Gutenberg
+ * @subpackage style-engine
+ */
+
+require __DIR__ . '/../class-wp-style-engine-css-rule.php';
+require __DIR__ . '/../class-wp-style-engine-css-declarations.php';
+
+/**
+ * Tests for registering, storing and generating CSS declarations.
+ */
+class WP_Style_Engine_CSS_Rule_Test extends WP_UnitTestCase {
+	/**
+	 * Should set declarations on instantiation.
+	 */
+	public function test_instantiate_with_selector_and_rules() {
+		$selector           = '.law-and-order';
+		$input_declarations = array(
+			'margin-top' => '10px',
+			'font-size'  => '2rem',
+		);
+		$css_declarations   = new WP_Style_Engine_CSS_Declarations( $input_declarations );
+		$css_rule           = new WP_Style_Engine_CSS_Rule( $selector, $css_declarations );
+
+		$this->assertSame( $selector, $css_rule->get_selector() );
+
+		$expected = "$selector {{$css_declarations->get_declarations_string()}}";
+		$this->assertSame( $expected, $css_rule->get_css() );
+	}
+
+	/**
+	 * Test dedupe declaration properties.
+	 */
+	public function test_dedupe_properties_in_rules() {
+		$selector                    = '.taggart';
+		$first_declaration           = array(
+			'font-size' => '2rem',
+		);
+		$overwrite_first_declaration = array(
+			'font-size' => '4px',
+		);
+		$css_rule                    = new WP_Style_Engine_CSS_Rule( $selector, $first_declaration );
+		$css_rule->set_declarations( new WP_Style_Engine_CSS_Declarations( $overwrite_first_declaration ) );
+
+		$expected = '.taggart {font-size: 4px;}';
+		$this->assertSame( $expected, $css_rule->get_css() );
+	}
+
+	/**
+	 * Should set selector and rules on instantiation.
+	 */
+	public function test_set_declarations() {
+		// Declarations using a WP_Style_Engine_CSS_Declarations object.
+		$some_css_declarations = new WP_Style_Engine_CSS_Declarations( array( 'margin-top' => '10px' ) );
+		// Declarations using a property => value array.
+		$some_more_css_declarations = array( 'font-size' => '1rem' );
+		$css_rule                   = new WP_Style_Engine_CSS_Rule( '.hill-street-blues', $some_css_declarations );
+		$css_rule->set_declarations( $some_more_css_declarations );
+
+		$expected = '.hill-street-blues {margin-top: 10px; font-size: 1rem;}';
+		$this->assertSame( $expected, $css_rule->get_css() );
+	}
+
+	/**
+	 * Should set selector and rules on instantiation.
+	 */
+	public function test_set_selector() {
+		$selector = '.taggart';
+		$css_rule = new WP_Style_Engine_CSS_Rule( $selector );
+
+		$this->assertSame( $selector, $css_rule->get_selector() );
+
+		$css_rule->set_selector( '.law-and-order' );
+
+		$this->assertSame( '.law-and-order', $css_rule->get_selector() );
+	}
+
+	/**
+	 * Should set selector and rules on instantiation.
+	 */
+	public function test_get_css() {
+		$selector           = '.chips';
+		$input_declarations = array(
+			'margin-top' => '10px',
+			'font-size'  => '2rem',
+		);
+		$css_declarations   = new WP_Style_Engine_CSS_Declarations( $input_declarations );
+		$css_rule           = new WP_Style_Engine_CSS_Rule( $selector, $css_declarations );
+		$expected           = "$selector {{$css_declarations->get_declarations_string()}}";
+
+		$this->assertSame( $expected, $css_rule->get_css() );
+	}
+}
diff --git a/packages/style-engine/phpunit/class-wp-style-engine-css-rules-store-test.php b/packages/style-engine/phpunit/class-wp-style-engine-css-rules-store-test.php
new file mode 100644
index 00000000000000..390700a9e5ac48
--- /dev/null
+++ b/packages/style-engine/phpunit/class-wp-style-engine-css-rules-store-test.php
@@ -0,0 +1,115 @@
+<?php
+/**
+ * Tests the Style Engine CSS Rules Store class.
+ *
+ * @package    Gutenberg
+ * @subpackage style-engine
+ */
+
+require __DIR__ . '/../class-wp-style-engine-css-rules-store.php';
+require __DIR__ . '/../class-wp-style-engine-css-rule.php';
+require __DIR__ . '/../class-wp-style-engine-css-declarations.php';
+
+/**
+ * Tests for registering, storing and retrieving CSS Rules.
+ */
+class WP_Style_Engine_CSS_Rules_Store_Test extends WP_UnitTestCase {
+	/**
+	 * Should create a new store.
+	 */
+	public function test_create_new_store() {
+		$new_pancakes_store = WP_Style_Engine_CSS_Rules_Store::get_store( 'pancakes-with-strawberries' );
+		$this->assertInstanceOf( 'WP_Style_Engine_CSS_Rules_Store', $new_pancakes_store );
+	}
+
+	/**
+	 * Should return previously created store when the same selector key is passed.
+	 */
+	public function test_get_store() {
+		$new_fish_store = WP_Style_Engine_CSS_Rules_Store::get_store( 'fish-n-chips' );
+		$selector       = '.haddock';
+
+		$new_fish_store->get_rule( $selector )->get_selector();
+		$this->assertEquals( $selector, $new_fish_store->get_rule( $selector )->get_selector() );
+
+		$the_same_fish_store = WP_Style_Engine_CSS_Rules_Store::get_store( 'fish-n-chips' );
+		$this->assertEquals( $selector, $the_same_fish_store->get_rule( $selector )->get_selector() );
+	}
+
+	/**
+	 * Should return a stored rule.
+	 */
+	public function test_get_rule() {
+		$new_pie_store = WP_Style_Engine_CSS_Rules_Store::get_store( 'meat-pie' );
+		$selector      = '.wp-block-sauce a:hover';
+		$store_rule    = $new_pie_store->get_rule( $selector );
+		$expected      = "$selector {}";
+		$this->assertEquals( $expected, $store_rule->get_css() );
+
+		$pie_declarations = array(
+			'color'         => 'brown',
+			'border-color'  => 'yellow',
+			'border-radius' => '10rem',
+		);
+		$css_declarations = new WP_Style_Engine_CSS_Declarations( $pie_declarations );
+		$store_rule->set_declarations( $css_declarations );
+
+		$store_rule = $new_pie_store->get_rule( $selector );
+		$expected   = "$selector {{$css_declarations->get_declarations_string()}}";
+		$this->assertEquals( $expected, $store_rule->get_css() );
+	}
+
+	/**
+	 * Should return all stored rules.
+	 */
+	public function test_get_all_rules() {
+		$new_pizza_store = WP_Style_Engine_CSS_Rules_Store::get_store( 'pizza-with-mozzarella' );
+		$selector        = '.wp-block-anchovies a:hover';
+		$store_rule      = $new_pizza_store->get_rule( $selector );
+		$expected        = array(
+			$selector => $store_rule,
+		);
+
+		$this->assertEquals( $expected, $new_pizza_store->get_all_rules() );
+
+		$pizza_declarations = array(
+			'color'         => 'red',
+			'border-color'  => 'yellow',
+			'border-radius' => '10rem',
+		);
+		$css_declarations   = new WP_Style_Engine_CSS_Declarations( $pizza_declarations );
+		$store_rule->set_declarations( array( $css_declarations ) );
+
+		$expected = array(
+			$selector => $store_rule,
+		);
+		$this->assertEquals( $expected, $new_pizza_store->get_all_rules() );
+
+		$new_pizza_declarations = array(
+			'color'        => 'red',
+			'border-color' => 'red',
+			'font-size'    => '10rem',
+		);
+		$css_declarations       = new WP_Style_Engine_CSS_Declarations( $new_pizza_declarations );
+		$store_rule->set_declarations( array( $css_declarations ) );
+
+		$expected = array(
+			$selector => $store_rule,
+		);
+		$this->assertEquals( $expected, $new_pizza_store->get_all_rules() );
+
+		$new_selector             = '.wp-block-mushroom a:hover';
+		$newer_pizza_declarations = array(
+			'padding' => '100px',
+		);
+		$new_store_rule           = $new_pizza_store->get_rule( $new_selector );
+		$css_declarations         = new WP_Style_Engine_CSS_Declarations( $newer_pizza_declarations );
+		$new_store_rule->set_declarations( array( $css_declarations ) );
+
+		$expected = array(
+			$selector     => $store_rule,
+			$new_selector => $new_store_rule,
+		);
+		$this->assertEquals( $expected, $new_pizza_store->get_all_rules() );
+	}
+}

From 8deefb84993716664276c5582a50b7a8ee07b364 Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Fri, 15 Jul 2022 09:47:33 +0300
Subject: [PATCH 14/17] rename get_rule to add_rule

---
 .../class-wp-style-engine-css-rules-store.php    |  3 ++-
 ...lass-wp-style-engine-css-rules-store-test.php | 16 ++++++++--------
 2 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/packages/style-engine/class-wp-style-engine-css-rules-store.php b/packages/style-engine/class-wp-style-engine-css-rules-store.php
index bfc7fba9ecd71f..2e76fdb929330b 100644
--- a/packages/style-engine/class-wp-style-engine-css-rules-store.php
+++ b/packages/style-engine/class-wp-style-engine-css-rules-store.php
@@ -58,10 +58,11 @@ public function get_all_rules() {
 
 	/**
 	 * Get a WP_Style_Engine_CSS_Rule object by its selector.
+	 * If the rule does not exist, it will be created.
 	 *
 	 * @param string $selector The CSS selector.
 	 */
-	public function get_rule( $selector ) {
+	public function add_rule( $selector ) {
 
 		$selector = trim( $selector );
 
diff --git a/packages/style-engine/phpunit/class-wp-style-engine-css-rules-store-test.php b/packages/style-engine/phpunit/class-wp-style-engine-css-rules-store-test.php
index 390700a9e5ac48..b06c4d11d66f30 100644
--- a/packages/style-engine/phpunit/class-wp-style-engine-css-rules-store-test.php
+++ b/packages/style-engine/phpunit/class-wp-style-engine-css-rules-store-test.php
@@ -29,20 +29,20 @@ public function test_get_store() {
 		$new_fish_store = WP_Style_Engine_CSS_Rules_Store::get_store( 'fish-n-chips' );
 		$selector       = '.haddock';
 
-		$new_fish_store->get_rule( $selector )->get_selector();
-		$this->assertEquals( $selector, $new_fish_store->get_rule( $selector )->get_selector() );
+		$new_fish_store->add_rule( $selector )->get_selector();
+		$this->assertEquals( $selector, $new_fish_store->add_rule( $selector )->get_selector() );
 
 		$the_same_fish_store = WP_Style_Engine_CSS_Rules_Store::get_store( 'fish-n-chips' );
-		$this->assertEquals( $selector, $the_same_fish_store->get_rule( $selector )->get_selector() );
+		$this->assertEquals( $selector, $the_same_fish_store->add_rule( $selector )->get_selector() );
 	}
 
 	/**
 	 * Should return a stored rule.
 	 */
-	public function test_get_rule() {
+	public function test_add_rule() {
 		$new_pie_store = WP_Style_Engine_CSS_Rules_Store::get_store( 'meat-pie' );
 		$selector      = '.wp-block-sauce a:hover';
-		$store_rule    = $new_pie_store->get_rule( $selector );
+		$store_rule    = $new_pie_store->add_rule( $selector );
 		$expected      = "$selector {}";
 		$this->assertEquals( $expected, $store_rule->get_css() );
 
@@ -54,7 +54,7 @@ public function test_get_rule() {
 		$css_declarations = new WP_Style_Engine_CSS_Declarations( $pie_declarations );
 		$store_rule->set_declarations( $css_declarations );
 
-		$store_rule = $new_pie_store->get_rule( $selector );
+		$store_rule = $new_pie_store->add_rule( $selector );
 		$expected   = "$selector {{$css_declarations->get_declarations_string()}}";
 		$this->assertEquals( $expected, $store_rule->get_css() );
 	}
@@ -65,7 +65,7 @@ public function test_get_rule() {
 	public function test_get_all_rules() {
 		$new_pizza_store = WP_Style_Engine_CSS_Rules_Store::get_store( 'pizza-with-mozzarella' );
 		$selector        = '.wp-block-anchovies a:hover';
-		$store_rule      = $new_pizza_store->get_rule( $selector );
+		$store_rule      = $new_pizza_store->add_rule( $selector );
 		$expected        = array(
 			$selector => $store_rule,
 		);
@@ -102,7 +102,7 @@ public function test_get_all_rules() {
 		$newer_pizza_declarations = array(
 			'padding' => '100px',
 		);
-		$new_store_rule           = $new_pizza_store->get_rule( $new_selector );
+		$new_store_rule           = $new_pizza_store->add_rule( $new_selector );
 		$css_declarations         = new WP_Style_Engine_CSS_Declarations( $newer_pizza_declarations );
 		$new_store_rule->set_declarations( array( $css_declarations ) );
 

From c3bfa2f3beb204ee82081ddd1cc61a487f2bbf54 Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Fri, 15 Jul 2022 09:47:43 +0300
Subject: [PATCH 15/17] add a remove_rule method

---
 .../class-wp-style-engine-css-rules-store.php         | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/packages/style-engine/class-wp-style-engine-css-rules-store.php b/packages/style-engine/class-wp-style-engine-css-rules-store.php
index 2e76fdb929330b..28f0f78ac4f1c7 100644
--- a/packages/style-engine/class-wp-style-engine-css-rules-store.php
+++ b/packages/style-engine/class-wp-style-engine-css-rules-store.php
@@ -78,4 +78,15 @@ public function add_rule( $selector ) {
 
 		return $this->rules[ $selector ];
 	}
+
+	/**
+	 * Remove a selector from the store.
+	 *
+	 * @param string $selector The CSS selector.
+	 *
+	 * @return void
+	 */
+	public function remove_rule( $selector ) {
+		unset( $this->rules[ $selector ] );
+	}
 }

From a5f46e94e7c2d317e0cd2c37223738627bf26be9 Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Fri, 15 Jul 2022 10:21:16 +0300
Subject: [PATCH 16/17] minor performance improvement

---
 packages/style-engine/class-wp-style-engine-css-rule.php | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/packages/style-engine/class-wp-style-engine-css-rule.php b/packages/style-engine/class-wp-style-engine-css-rule.php
index e10c07183d21ae..855dd7ecc4b712 100644
--- a/packages/style-engine/class-wp-style-engine-css-rule.php
+++ b/packages/style-engine/class-wp-style-engine-css-rule.php
@@ -76,7 +76,9 @@ public function set_declarations( $declarations ) {
 
 		if ( null === $this->declarations && $is_declarations_object ) {
 			$this->declarations = $declarations;
-		} elseif ( null === $this->declarations ) {
+			return $this;
+		}
+		if ( null === $this->declarations ) {
 			$this->declarations = new WP_Style_Engine_CSS_Declarations( $declarations_array );
 		}
 		$this->declarations->add_declarations( $declarations_array );

From f85c3bd15e5a3324e183b2d53c95959417985749 Mon Sep 17 00:00:00 2001
From: Ari Stathopoulos <aristath@gmail.com>
Date: Fri, 15 Jul 2022 10:33:35 +0300
Subject: [PATCH 17/17] cleanup & added a return doc

---
 .../style-engine/class-wp-style-engine-css-rules-store.php    | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/packages/style-engine/class-wp-style-engine-css-rules-store.php b/packages/style-engine/class-wp-style-engine-css-rules-store.php
index 28f0f78ac4f1c7..1dc4da265accc7 100644
--- a/packages/style-engine/class-wp-style-engine-css-rules-store.php
+++ b/packages/style-engine/class-wp-style-engine-css-rules-store.php
@@ -43,7 +43,7 @@ class WP_Style_Engine_CSS_Rules_Store {
 	 */
 	public static function get_store( $store_name = 'default' ) {
 		if ( ! isset( static::$stores[ $store_name ] ) ) {
-			static::$stores[ $store_name ] = new static( $store_name );
+			static::$stores[ $store_name ] = new static();
 		}
 		return static::$stores[ $store_name ];
 	}
@@ -61,6 +61,8 @@ public function get_all_rules() {
 	 * If the rule does not exist, it will be created.
 	 *
 	 * @param string $selector The CSS selector.
+	 *
+	 * @return WP_Style_Engine_CSS_Rule|null Returns a WP_Style_Engine_CSS_Rule object, or null if the selector is empty.
 	 */
 	public function add_rule( $selector ) {