From e92b4515261e6407b97517e8cce994d5c07913c8 Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Thu, 4 Jan 2024 11:01:18 +0100
Subject: [PATCH 01/20] Update directive processing to handle namespaces

---
 .../directive-processing.php                  | 43 ++++++++++++++-----
 1 file changed, 32 insertions(+), 11 deletions(-)

diff --git a/lib/experimental/interactivity-api/directive-processing.php b/lib/experimental/interactivity-api/directive-processing.php
index 075d31d577634..c604bffeb549f 100644
--- a/lib/experimental/interactivity-api/directive-processing.php
+++ b/lib/experimental/interactivity-api/directive-processing.php
@@ -43,12 +43,13 @@ function gutenberg_process_directives_in_root_blocks( $block_content, $block ) {
 		$parsed_blocks     = parse_blocks( $block_content );
 		$context           = new WP_Directive_Context();
 		$processed_content = '';
+		$namespace_stack   = array();
 
 		foreach ( $parsed_blocks as $parsed_block ) {
 			if ( 'core/interactivity-wrapper' === $parsed_block['blockName'] ) {
-				$processed_content .= gutenberg_process_interactive_block( $parsed_block, $context );
+				$processed_content .= gutenberg_process_interactive_block( $parsed_block, $context, $namespace_stack );
 			} elseif ( 'core/non-interactivity-wrapper' === $parsed_block['blockName'] ) {
-				$processed_content .= gutenberg_process_non_interactive_block( $parsed_block, $context );
+				$processed_content .= gutenberg_process_non_interactive_block( $parsed_block, $context, $namespace_stack );
 			} else {
 				$processed_content .= $parsed_block['innerHTML'];
 			}
@@ -118,10 +119,11 @@ function gutenberg_mark_block_interactivity( $block_content, $block, $block_inst
  *
  * @param array                $interactive_block The interactive block to process.
  * @param WP_Directive_Context $context The context to use when processing.
+ * @param array                $namespace_stack Stack of namespackes passed by reference.
  *
  * @return string The processed HTML.
  */
-function gutenberg_process_interactive_block( $interactive_block, $context ) {
+function gutenberg_process_interactive_block( $interactive_block, $context, &$namespace_stack ) {
 	$block_index              = 0;
 	$content                  = '';
 	$interactive_inner_blocks = array();
@@ -137,7 +139,7 @@ function gutenberg_process_interactive_block( $interactive_block, $context ) {
 		}
 	}
 
-	return gutenberg_process_interactive_html( $content, $context, $interactive_inner_blocks );
+	return gutenberg_process_interactive_html( $content, $context, $interactive_inner_blocks, $namespace_stack );
 }
 
 /**
@@ -147,10 +149,11 @@ function gutenberg_process_interactive_block( $interactive_block, $context ) {
  *
  * @param array                $non_interactive_block The non-interactive block to process.
  * @param WP_Directive_Context $context The context to use when processing.
+ * @param array                $namespace_stack Stack of namespackes passed by reference.
  *
  * @return string The processed HTML.
  */
-function gutenberg_process_non_interactive_block( $non_interactive_block, $context ) {
+function gutenberg_process_non_interactive_block( $non_interactive_block, $context, &$namespace_stack ) {
 	$block_index = 0;
 	$content     = '';
 	foreach ( $non_interactive_block['innerContent'] as $inner_content ) {
@@ -164,9 +167,9 @@ function gutenberg_process_non_interactive_block( $non_interactive_block, $conte
 			$inner_block = $non_interactive_block['innerBlocks'][ $block_index++ ];
 
 			if ( 'core/interactivity-wrapper' === $inner_block['blockName'] ) {
-				$content .= gutenberg_process_interactive_block( $inner_block, $context );
+				$content .= gutenberg_process_interactive_block( $inner_block, $context, $namespace_stack );
 			} elseif ( 'core/non-interactivity-wrapper' === $inner_block['blockName'] ) {
-				$content .= gutenberg_process_non_interactive_block( $inner_block, $context );
+				$content .= gutenberg_process_non_interactive_block( $inner_block, $context, $namespace_stack );
 			}
 		}
 	}
@@ -184,10 +187,11 @@ function gutenberg_process_non_interactive_block( $non_interactive_block, $conte
  * @param string $html The HTML to process.
  * @param mixed  $context The context to use when processing.
  * @param array  $inner_blocks The inner blocks to process.
+ * @param array  $namespace_stack Stack of namespackes passed by reference.
  *
  * @return string The processed HTML.
  */
-function gutenberg_process_interactive_html( $html, $context, $inner_blocks = array() ) {
+function gutenberg_process_interactive_html( $html, $context, $inner_blocks = array(), &$namespace_stack = array() ) {
 	static $directives = array(
 		'data-wp-context' => 'gutenberg_interactivity_process_wp_context',
 		'data-wp-bind'    => 'gutenberg_interactivity_process_wp_bind',
@@ -207,9 +211,9 @@ function gutenberg_process_interactive_html( $html, $context, $inner_blocks = ar
 		// Processes the inner blocks.
 		if ( str_contains( $tag_name, 'WP-INNER-BLOCKS' ) && ! empty( $inner_blocks ) && ! $tags->is_tag_closer() ) {
 			if ( 'core/interactivity-wrapper' === $inner_blocks[ $inner_blocks_index ]['blockName'] ) {
-				$inner_processed_blocks[ strtolower( $tag_name ) ] = gutenberg_process_interactive_block( $inner_blocks[ $inner_blocks_index++ ], $context );
+				$inner_processed_blocks[ strtolower( $tag_name ) ] = gutenberg_process_interactive_block( $inner_blocks[ $inner_blocks_index++ ], $context, $namespace_stack );
 			} elseif ( 'core/non-interactivity-wrapper' === $inner_blocks[ $inner_blocks_index ]['blockName'] ) {
-				$inner_processed_blocks[ strtolower( $tag_name ) ] = gutenberg_process_non_interactive_block( $inner_blocks[ $inner_blocks_index++ ], $context );
+				$inner_processed_blocks[ strtolower( $tag_name ) ] = gutenberg_process_non_interactive_block( $inner_blocks[ $inner_blocks_index++ ], $context, $namespace_stack );
 			}
 		}
 		if ( $tags->is_tag_closer() ) {
@@ -269,8 +273,25 @@ function gutenberg_process_interactive_html( $html, $context, $inner_blocks = ar
 			$attributes
 		);
 
+		// Push the new namespace if the current tag is an island.
+		$island = $tags->get_attribute( 'data-wp-interactive' );
+		if ( isset( $island ) && ! $tags->is_tag_closer() ) {
+			$island_data       = json_decode( $island, true );
+			$namespace_stack[] = $island_data['namespace'];
+		}
+
 		foreach ( $sorted_attrs as $attribute ) {
-			call_user_func( $directives[ $attribute ], $tags, $context );
+			call_user_func(
+				$directives[ $attribute ],
+				$tags,
+				$context,
+				end( $namespace_stack )
+			);
+		}
+
+		// Pop the current namespace if this is the closing tag of an island.
+		if ( isset( $island ) && $tags->is_tag_closer() ) {
+			array_pop( $namespace_stack );
 		}
 	}
 

From 2d42cfa7a7cf839fb2a0f279acb5488e7e8f15b7 Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Thu, 4 Jan 2024 11:13:04 +0100
Subject: [PATCH 02/20] Add required namespace param to evaluate reference

---
 .../interactivity-api/directive-processing.php             | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/lib/experimental/interactivity-api/directive-processing.php b/lib/experimental/interactivity-api/directive-processing.php
index c604bffeb549f..6b30a791d08b5 100644
--- a/lib/experimental/interactivity-api/directive-processing.php
+++ b/lib/experimental/interactivity-api/directive-processing.php
@@ -314,14 +314,15 @@ function gutenberg_process_interactive_html( $html, $context, $inner_blocks = ar
  * Resolves the reference using the store and the context from the provided
  * path.
  *
+ * @param string $ns Namespace.
  * @param string $path Path.
  * @param array  $context Context data.
  * @return mixed
  */
-function gutenberg_interactivity_evaluate_reference( $path, array $context = array() ) {
+function gutenberg_interactivity_evaluate_reference( $ns, $path, array $context = array() ) {
 	$store = array_merge(
-		WP_Interactivity_Store::get_data(),
-		array( 'context' => $context )
+		WP_Interactivity_Store::get_data()[ $ns ],
+		array( 'context' => $context[ $ns ] )
 	);
 
 	/*

From 319e37656913fc9ecdf34dce4937fd3fa15f9b4d Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Thu, 4 Jan 2024 12:14:23 +0100
Subject: [PATCH 03/20] Handle references with namespaces

---
 .../class-wp-directive-processor.php          | 18 +++++++++++++
 .../directive-processing.php                  | 25 ++++++++++++-------
 2 files changed, 34 insertions(+), 9 deletions(-)

diff --git a/lib/experimental/interactivity-api/class-wp-directive-processor.php b/lib/experimental/interactivity-api/class-wp-directive-processor.php
index bb70068aa9482..a2a300b3538f8 100644
--- a/lib/experimental/interactivity-api/class-wp-directive-processor.php
+++ b/lib/experimental/interactivity-api/class-wp-directive-processor.php
@@ -256,4 +256,22 @@ public static function is_html_void_element( $tag_name ) {
 	public static function parse_attribute_name( $name ) {
 		return explode( '--', $name, 2 );
 	}
+
+	/**
+	 * Parse and extract the namespace and path from the given reference.
+	 *
+	 * @param string $reference Passed reference.
+	 * @param string $ns Namespace fallback.
+	 * @return array The resulting array
+	 */
+	public static function parse_reference( $reference, $ns_fallback = null ) {
+		$matches = array();
+		$has_ns  = preg_match( '/^([\w\-_\/]+)::(.+)$/', $reference, $matches );
+
+		if ( $has_ns ) {
+			return array_slice( $matches, 1 );
+		} else {
+			return array( $ns_fallback, $reference );
+		}
+	}
 }
diff --git a/lib/experimental/interactivity-api/directive-processing.php b/lib/experimental/interactivity-api/directive-processing.php
index 6b30a791d08b5..2a7d9d95a7c75 100644
--- a/lib/experimental/interactivity-api/directive-processing.php
+++ b/lib/experimental/interactivity-api/directive-processing.php
@@ -311,18 +311,25 @@ function gutenberg_process_interactive_html( $html, $context, $inner_blocks = ar
 }
 
 /**
- * Resolves the reference using the store and the context from the provided
- * path.
+ * Resolves the passed reference from the store and the context under the given
+ * namespace.
  *
- * @param string $ns Namespace.
- * @param string $path Path.
+ * A reference could be either a single path or a namespace followed by a path,
+ * separated by two colons, i.e, `namespace::path.to.prop`. If the reference
+ * contains a namespace, that namespace overrides the one passed as argument.
+ *
+ * @param string $reference Reference value.
+ * @param string $ns Inherited namespace.
  * @param array  $context Context data.
- * @return mixed
+ * @return mixed Resolved value.
  */
-function gutenberg_interactivity_evaluate_reference( $ns, $path, array $context = array() ) {
-	$store = array_merge(
-		WP_Interactivity_Store::get_data()[ $ns ],
-		array( 'context' => $context[ $ns ] )
+function gutenberg_interactivity_evaluate_reference( $reference, $ns, array $context = array() ) {
+	// Extract the namespace from the reference (if present).
+	list( $ns, $path ) = WP_Directive_Processor::parse_reference( $reference, $ns );
+
+	$store = array(
+		'state'   => WP_Interactivity_Store::get_data()[ $ns ],
+		'context' => $context[ $ns ] ?? array(),
 	);
 
 	/*

From 6e1ffa588d0f1afab0638cf1f1a10d9c90abeca3 Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Thu, 4 Jan 2024 13:15:29 +0100
Subject: [PATCH 04/20] Rename parse_reference to parse_attribute_value

---
 .../class-wp-directive-processor.php          | 23 +++++++++++++------
 .../directive-processing.php                  |  2 +-
 2 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/lib/experimental/interactivity-api/class-wp-directive-processor.php b/lib/experimental/interactivity-api/class-wp-directive-processor.php
index a2a300b3538f8..22ba18defe55e 100644
--- a/lib/experimental/interactivity-api/class-wp-directive-processor.php
+++ b/lib/experimental/interactivity-api/class-wp-directive-processor.php
@@ -258,20 +258,29 @@ public static function parse_attribute_name( $name ) {
 	}
 
 	/**
-	 * Parse and extract the namespace and path from the given reference.
+	 * Parse and extract the namespace and path from the given value.
 	 *
-	 * @param string $reference Passed reference.
+	 * If the value contains a JSON instead of a path, the function parses it
+	 * and returns the resulting array.
+	 *
+	 * @param string $value Passed value.
 	 * @param string $ns Namespace fallback.
 	 * @return array The resulting array
 	 */
-	public static function parse_reference( $reference, $ns_fallback = null ) {
+	public static function parse_attribute_value( $value, $ns = null ) {
 		$matches = array();
-		$has_ns  = preg_match( '/^([\w\-_\/]+)::(.+)$/', $reference, $matches );
+		$has_ns  = preg_match( '/^([\w\-_\/]+)::(.+)$/', $value, $matches );
 
 		if ( $has_ns ) {
-			return array_slice( $matches, 1 );
-		} else {
-			return array( $ns_fallback, $reference );
+			list( , $ns, $value ) = $matches;
+		}
+
+		// Try parsing the value.
+		$data = json_decode( $value, true );
+		if ( null !== $data || 'null' === trim( $value ) ) {
+			$value = $data;
 		}
+
+		return array( $ns, $value );
 	}
 }
diff --git a/lib/experimental/interactivity-api/directive-processing.php b/lib/experimental/interactivity-api/directive-processing.php
index 2a7d9d95a7c75..12269eab99b20 100644
--- a/lib/experimental/interactivity-api/directive-processing.php
+++ b/lib/experimental/interactivity-api/directive-processing.php
@@ -325,7 +325,7 @@ function gutenberg_process_interactive_html( $html, $context, $inner_blocks = ar
  */
 function gutenberg_interactivity_evaluate_reference( $reference, $ns, array $context = array() ) {
 	// Extract the namespace from the reference (if present).
-	list( $ns, $path ) = WP_Directive_Processor::parse_reference( $reference, $ns );
+	list( $ns, $path ) = WP_Directive_Processor::parse_attribute_value( $reference, $ns );
 
 	$store = array(
 		'state'   => WP_Interactivity_Store::get_data()[ $ns ],

From 9e5f801fcc3c9e9ab85fda7c13441a8ae3335ef5 Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Thu, 4 Jan 2024 13:21:43 +0100
Subject: [PATCH 05/20] Update directive implementations

---
 .../interactivity-api/directives/wp-bind.php       |  7 ++++---
 .../interactivity-api/directives/wp-class.php      |  7 ++++---
 .../interactivity-api/directives/wp-context.php    | 14 +++++++-------
 .../interactivity-api/directives/wp-style.php      |  7 ++++---
 .../interactivity-api/directives/wp-text.php       |  5 +++--
 5 files changed, 22 insertions(+), 18 deletions(-)

diff --git a/lib/experimental/interactivity-api/directives/wp-bind.php b/lib/experimental/interactivity-api/directives/wp-bind.php
index 54be4a9faeb7d..57d2e5deb23ab 100644
--- a/lib/experimental/interactivity-api/directives/wp-bind.php
+++ b/lib/experimental/interactivity-api/directives/wp-bind.php
@@ -11,8 +11,9 @@
  *
  * @param WP_Directive_Processor $tags Tags.
  * @param WP_Directive_Context   $context Directive context.
+ * @param string                 $ns Namespace.
  */
-function gutenberg_interactivity_process_wp_bind( $tags, $context ) {
+function gutenberg_interactivity_process_wp_bind( $tags, $context, $ns ) {
 	if ( $tags->is_tag_closer() ) {
 		return;
 	}
@@ -25,8 +26,8 @@ function gutenberg_interactivity_process_wp_bind( $tags, $context ) {
 			continue;
 		}
 
-		$expr  = $tags->get_attribute( $attr );
-		$value = gutenberg_interactivity_evaluate_reference( $expr, $context->get_context() );
+		$reference = $tags->get_attribute( $attr );
+		$value     = gutenberg_interactivity_evaluate_reference( $reference, $ns, $context->get_context() );
 		$tags->set_attribute( $bound_attr, $value );
 	}
 }
diff --git a/lib/experimental/interactivity-api/directives/wp-class.php b/lib/experimental/interactivity-api/directives/wp-class.php
index 741cc75b42c60..ef91835be86fc 100644
--- a/lib/experimental/interactivity-api/directives/wp-class.php
+++ b/lib/experimental/interactivity-api/directives/wp-class.php
@@ -11,8 +11,9 @@
  *
  * @param WP_Directive_Processor $tags Tags.
  * @param WP_Directive_Context   $context Directive context.
+ * @param string                 $ns Namespace.
  */
-function gutenberg_interactivity_process_wp_class( $tags, $context ) {
+function gutenberg_interactivity_process_wp_class( $tags, $context, $ns ) {
 	if ( $tags->is_tag_closer() ) {
 		return;
 	}
@@ -25,8 +26,8 @@ function gutenberg_interactivity_process_wp_class( $tags, $context ) {
 			continue;
 		}
 
-		$expr      = $tags->get_attribute( $attr );
-		$add_class = gutenberg_interactivity_evaluate_reference( $expr, $context->get_context() );
+		$reference = $tags->get_attribute( $attr );
+		$add_class = gutenberg_interactivity_evaluate_reference( $reference, $ns, $context->get_context() );
 		if ( $add_class ) {
 			$tags->add_class( $class_name );
 		} else {
diff --git a/lib/experimental/interactivity-api/directives/wp-context.php b/lib/experimental/interactivity-api/directives/wp-context.php
index 7d92b0ac7b0c6..43bfcfa926d2f 100644
--- a/lib/experimental/interactivity-api/directives/wp-context.php
+++ b/lib/experimental/interactivity-api/directives/wp-context.php
@@ -10,19 +10,19 @@
  *
  * @param WP_Directive_Processor $tags Tags.
  * @param WP_Directive_Context   $context Directive context.
+ * @param string                 $ns Namespace.
  */
-function gutenberg_interactivity_process_wp_context( $tags, $context ) {
+function gutenberg_interactivity_process_wp_context( $tags, $context, $ns ) {
 	if ( $tags->is_tag_closer() ) {
 		$context->rewind_context();
 		return;
 	}
 
-	$value = $tags->get_attribute( 'data-wp-context' );
+	$attr_value = $tags->get_attribute( 'data-wp-context' );
 
-	$new_context = json_decode(
-		is_string( $value ) && ! empty( $value ) ? $value : '{}',
-		true
-	);
+	//Separate namespace and value from the context directive attribute.
+	list( $ns, $data ) = WP_Directive_Processor::parse_attribute_value( $attr_value, $ns );
 
-	$context->set_context( $new_context ?? array() );
+	// Add parsed data to the context under the corresponding namespace.
+	$context->set_context( array( $ns => is_array( $data ) ? $data : array() ) );
 }
diff --git a/lib/experimental/interactivity-api/directives/wp-style.php b/lib/experimental/interactivity-api/directives/wp-style.php
index e5d7b269ace7c..16432e5728260 100644
--- a/lib/experimental/interactivity-api/directives/wp-style.php
+++ b/lib/experimental/interactivity-api/directives/wp-style.php
@@ -11,8 +11,9 @@
  *
  * @param WP_Directive_Processor $tags Tags.
  * @param WP_Directive_Context   $context Directive context.
+ * @param string                 $ns Namespace.
  */
-function gutenberg_interactivity_process_wp_style( $tags, $context ) {
+function gutenberg_interactivity_process_wp_style( $tags, $context, $ns ) {
 	if ( $tags->is_tag_closer() ) {
 		return;
 	}
@@ -25,8 +26,8 @@ function gutenberg_interactivity_process_wp_style( $tags, $context ) {
 			continue;
 		}
 
-		$expr        = $tags->get_attribute( $attr );
-		$style_value = gutenberg_interactivity_evaluate_reference( $expr, $context->get_context() );
+		$reference   = $tags->get_attribute( $attr );
+		$style_value = gutenberg_interactivity_evaluate_reference( $reference, $ns, $context->get_context() );
 		if ( $style_value ) {
 			$style_attr = $tags->get_attribute( 'style' ) ?? '';
 			$style_attr = gutenberg_interactivity_set_style( $style_attr, $style_name, $style_value );
diff --git a/lib/experimental/interactivity-api/directives/wp-text.php b/lib/experimental/interactivity-api/directives/wp-text.php
index b0cfc98a74e70..c4c5bb27a31e1 100644
--- a/lib/experimental/interactivity-api/directives/wp-text.php
+++ b/lib/experimental/interactivity-api/directives/wp-text.php
@@ -11,8 +11,9 @@
  *
  * @param WP_Directive_Processor $tags Tags.
  * @param WP_Directive_Context   $context Directive context.
+ * @param string                 $ns Namespace.
  */
-function gutenberg_interactivity_process_wp_text( $tags, $context ) {
+function gutenberg_interactivity_process_wp_text( $tags, $context, $ns ) {
 	if ( $tags->is_tag_closer() ) {
 		return;
 	}
@@ -22,6 +23,6 @@ function gutenberg_interactivity_process_wp_text( $tags, $context ) {
 		return;
 	}
 
-	$text = gutenberg_interactivity_evaluate_reference( $value, $context->get_context() );
+	$text = gutenberg_interactivity_evaluate_reference( $value, $ns, $context->get_context() );
 	$tags->set_inner_html( esc_html( $text ) );
 }

From 262017414d8fc1e7cdd2123a177787c6d3607eaa Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Thu, 4 Jan 2024 16:54:13 +0100
Subject: [PATCH 06/20] Improve comments in `parse_attribute_value`

---
 .../class-wp-directive-processor.php               | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/lib/experimental/interactivity-api/class-wp-directive-processor.php b/lib/experimental/interactivity-api/class-wp-directive-processor.php
index 22ba18defe55e..0b5d63e2a25aa 100644
--- a/lib/experimental/interactivity-api/class-wp-directive-processor.php
+++ b/lib/experimental/interactivity-api/class-wp-directive-processor.php
@@ -271,11 +271,23 @@ public static function parse_attribute_value( $value, $ns = null ) {
 		$matches = array();
 		$has_ns  = preg_match( '/^([\w\-_\/]+)::(.+)$/', $value, $matches );
 
+		/*
+		 * Overwrite both `$ns` and `$value` variables if `$value` explicitly
+		 * contains a namespace.
+		 */
 		if ( $has_ns ) {
 			list( , $ns, $value ) = $matches;
 		}
 
-		// Try parsing the value.
+		/*
+		 * Try to decode `$value` as a JSON object. If it works, `$value` is
+		 * replaced with the resulting array. The original string is preserved
+		 * otherwise.
+		 *
+		 * Note that `json_decode` returns `null` both for an invalid JSON or
+		 * the `'null'` string (a valid JSON). In the latter case, `$value` is
+		 * replaced with `null`.
+		 */
 		$data = json_decode( $value, true );
 		if ( null !== $data || 'null' === trim( $value ) ) {
 			$value = $data;

From 80694be2a7e2dd989a72d2bd4fb0433866851c65 Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Wed, 29 Nov 2023 18:24:29 +0100
Subject: [PATCH 07/20] Restore changes from `store()` migration PR

---
 .../class-wp-interactivity-initial-state.php  |  85 ++++++++
 .../class-wp-interactivity-store.php          |  69 -------
 .../interactivity-api/initial-state.php       |  29 +++
 lib/experimental/interactivity-api/store.php  |  28 ---
 lib/load.php                                  |   4 +-
 ...ss-wp-interactivity-initial-state-test.php | 111 +++++++++++
 .../class-wp-interactivity-store-test.php     | 186 ------------------
 7 files changed, 227 insertions(+), 285 deletions(-)
 create mode 100644 lib/experimental/interactivity-api/class-wp-interactivity-initial-state.php
 delete mode 100644 lib/experimental/interactivity-api/class-wp-interactivity-store.php
 create mode 100644 lib/experimental/interactivity-api/initial-state.php
 delete mode 100644 lib/experimental/interactivity-api/store.php
 create mode 100644 phpunit/experimental/interactivity-api/class-wp-interactivity-initial-state-test.php
 delete mode 100644 phpunit/experimental/interactivity-api/class-wp-interactivity-store-test.php

diff --git a/lib/experimental/interactivity-api/class-wp-interactivity-initial-state.php b/lib/experimental/interactivity-api/class-wp-interactivity-initial-state.php
new file mode 100644
index 0000000000000..a1edbcff776fb
--- /dev/null
+++ b/lib/experimental/interactivity-api/class-wp-interactivity-initial-state.php
@@ -0,0 +1,85 @@
+<?php
+/**
+ * WP_Interactivity_Initial_State class
+ *
+ * @package Gutenberg
+ * @subpackage Interactivity API
+ */
+
+if ( class_exists( 'WP_Interactivity_Initial_State' ) ) {
+	return;
+}
+
+/**
+ * Manages the initial state of the Interactivity API store in the server and
+ * its serialization so it can be restored in the browser upon hydration.
+ *
+ * @package Gutenberg
+ * @subpackage Interactivity API
+ */
+class WP_Interactivity_Initial_State {
+	/**
+	 * Map of initial state by namespace.
+	 *
+	 * @var array
+	 */
+	private static $initial_state = array();
+
+	/**
+	 * Get state from a given namespace.
+	 *
+	 * @param string $store_ns Namespace.
+	 *
+	 * @return array The requested state.
+	 */
+	public static function get_state( $store_ns = null ) {
+		if ( ! $store_ns ) {
+			return self::$initial_state;
+		}
+		return self::$initial_state[ $store_ns ] ?? array();
+	}
+
+	/**
+	 * Merge data into the state with the given namespace.
+	 *
+	 * @param string $store_ns Namespace.
+	 * @param array  $data      State to merge.
+	 *
+	 * @return void
+	 */
+	public static function merge_state( $store_ns, $data ) {
+		self::$initial_state[ $store_ns ] = array_replace_recursive(
+			self::get_state( $store_ns ),
+			$data
+		);
+	}
+
+	/**
+	 * Get store data.
+	 *
+	 * @return array
+	 */
+	public static function get_data() {
+		return self::$initial_state;
+	}
+
+	/**
+	 * Reset the initial state.
+	 */
+	public static function reset() {
+		self::$initial_state = array();
+	}
+
+	/**
+	 * Render the initial state.
+	 */
+	public static function render() {
+		if ( empty( self::$initial_state ) ) {
+			return;
+		}
+		echo sprintf(
+			'<script id="wp-interactivity-initial-state" type="application/json">%s</script>',
+			wp_json_encode( self::$initial_state, JSON_HEX_TAG | JSON_HEX_AMP )
+		);
+	}
+}
diff --git a/lib/experimental/interactivity-api/class-wp-interactivity-store.php b/lib/experimental/interactivity-api/class-wp-interactivity-store.php
deleted file mode 100644
index c53701b14e8af..0000000000000
--- a/lib/experimental/interactivity-api/class-wp-interactivity-store.php
+++ /dev/null
@@ -1,69 +0,0 @@
-<?php
-/**
- * WP_Interactivity_Store class
- *
- * Manages the initial state of the Interactivity API store in the server and
- * its serialization so it can be restored in the browser upon hydration.
- *
- * @package Gutenberg
- * @subpackage Interactivity API
- */
-
-if ( class_exists( 'WP_Interactivity_Store' ) ) {
-	return;
-}
-
-/**
- * Manages the initial state of the Interactivity API store in the server and
- * its serialization so it can be restored in the browser upon hydration.
- *
- * It's a private class, exposed by other functions, like `wp_store`.
- *
- * @access private
- */
-class WP_Interactivity_Store {
-	/**
-	 * Store.
-	 *
-	 * @var array
-	 */
-	private static $store = array();
-
-	/**
-	 * Get store data.
-	 *
-	 * @return array
-	 */
-	public static function get_data() {
-		return self::$store;
-	}
-
-	/**
-	 * Merge data.
-	 *
-	 * @param array $data The data that will be merged with the existing store.
-	 */
-	public static function merge_data( $data ) {
-		self::$store = array_replace_recursive( self::$store, $data );
-	}
-
-	/**
-	 * Reset the store data.
-	 */
-	public static function reset() {
-		self::$store = array();
-	}
-
-	/**
-	 * Render the store data.
-	 */
-	public static function render() {
-		if ( empty( self::$store ) ) {
-			return;
-		}
-		echo sprintf(
-			'<script id="wp-interactivity-initial-state" type="application/json">%s</script>',
-			wp_json_encode( self::$store, JSON_HEX_TAG | JSON_HEX_AMP )
-		);
-	}
-}
diff --git a/lib/experimental/interactivity-api/initial-state.php b/lib/experimental/interactivity-api/initial-state.php
new file mode 100644
index 0000000000000..a38d0da631f3c
--- /dev/null
+++ b/lib/experimental/interactivity-api/initial-state.php
@@ -0,0 +1,29 @@
+<?php
+/**
+ * Functions to expose the store of the WP_Interactivity_Initial_State class.
+ *
+ * @package Gutenberg
+ * @subpackage Interactivity API
+ */
+
+if ( ! function_exists( 'wp_initial_state' ) ) {
+	/**
+	 * Merge data into the state with the given namespace.
+	 *
+	 * @param string $store_ns  Namespace.
+	 * @param array  $data      State to merge.
+	 *
+	 * @return array The current state for the given namespace.
+	 */
+	function wp_initial_state( $store_ns, $data = null ) {
+		if ( $data ) {
+			WP_Interactivity_Initial_State::merge_state( $store_ns, $data );
+		}
+		return WP_Interactivity_Initial_State::get_state( $store_ns );
+	}
+
+	/**
+	 * Render the Interactivity API initial state in the frontend.
+	 */
+	add_action( 'wp_footer', array( 'WP_Interactivity_Initial_State', 'render' ), 8 );
+}
diff --git a/lib/experimental/interactivity-api/store.php b/lib/experimental/interactivity-api/store.php
deleted file mode 100644
index 05c8b35f780d4..0000000000000
--- a/lib/experimental/interactivity-api/store.php
+++ /dev/null
@@ -1,28 +0,0 @@
-<?php
-/**
- * Functions to expose the store of the WP_Interactivity_Store class.
- *
- * @package Gutenberg
- * @subpackage Interactivity API
- */
-
-if ( ! function_exists( 'wp_store' ) ) {
-	/**
-	 * Merge data with the existing store.
-	 *
-	 * @param array $data Data that will be merged with the existing store.
-	 *
-	 * @return $data The current store data.
-	 */
-	function wp_store( $data = null ) {
-		if ( $data ) {
-			WP_Interactivity_Store::merge_data( $data );
-		}
-		return WP_Interactivity_Store::get_data();
-	}
-}
-
-/**
- * Render the Interactivity API store in the frontend.
- */
-add_action( 'wp_footer', array( 'WP_Interactivity_Store', 'render' ), 8 );
diff --git a/lib/load.php b/lib/load.php
index 1aa55f7581c27..f8335a141e57f 100644
--- a/lib/load.php
+++ b/lib/load.php
@@ -117,8 +117,8 @@ function gutenberg_is_experiment_enabled( $name ) {
 	require __DIR__ . '/experimental/disable-tinymce.php';
 }
 
-require __DIR__ . '/experimental/interactivity-api/class-wp-interactivity-store.php';
-require __DIR__ . '/experimental/interactivity-api/store.php';
+require __DIR__ . '/experimental/interactivity-api/class-wp-interactivity-initial-state.php';
+require __DIR__ . '/experimental/interactivity-api/initial-state.php';
 require __DIR__ . '/experimental/interactivity-api/modules.php';
 require __DIR__ . '/experimental/interactivity-api/class-wp-directive-processor.php';
 require __DIR__ . '/experimental/interactivity-api/class-wp-directive-context.php';
diff --git a/phpunit/experimental/interactivity-api/class-wp-interactivity-initial-state-test.php b/phpunit/experimental/interactivity-api/class-wp-interactivity-initial-state-test.php
new file mode 100644
index 0000000000000..ece4ee9c39f01
--- /dev/null
+++ b/phpunit/experimental/interactivity-api/class-wp-interactivity-initial-state-test.php
@@ -0,0 +1,111 @@
+<?php
+/**
+ * `WP_Interactivity_Initial_State` class test.
+ *
+ * @package Gutenberg
+ * @subpackage Interactivity API
+ */
+
+/**
+ * Tests for the `WP_Interactivity_Initial_State` class.
+ *
+ * @group  interactivity-api
+ * @covers WP_Interactivity_Initial_State
+ */
+class WP_Interactivity_Initial_State_Test extends WP_UnitTestCase {
+	public function set_up() {
+		// Clear the state before each test.
+		WP_Interactivity_Initial_State::reset();
+	}
+
+	public function test_initial_state_should_be_empty() {
+		$this->assertEmpty( WP_Interactivity_Initial_State::get_data() );
+	}
+
+	public function test_initial_state_can_be_merged() {
+		$state = array(
+			'a'      => 1,
+			'b'      => 2,
+			'nested' => array(
+				'c' => 3,
+			),
+		);
+		WP_Interactivity_Initial_State::merge_state( 'core', $state );
+		$this->assertSame( $state, WP_Interactivity_Initial_State::get_state( 'core' ) );
+	}
+
+	public function test_initial_state_can_be_extended() {
+		WP_Interactivity_Initial_State::merge_state( 'core', array( 'a' => 1 ) );
+		WP_Interactivity_Initial_State::merge_state( 'core', array( 'b' => 2 ) );
+		WP_Interactivity_Initial_State::merge_state( 'custom', array( 'c' => 3 ) );
+		$this->assertSame(
+			array(
+				'core'   => array(
+					'a' => 1,
+					'b' => 2,
+				),
+				'custom' => array(
+					'c' => 3,
+				),
+			),
+			WP_Interactivity_Initial_State::get_data()
+		);
+	}
+
+	public function test_initial_state_existing_props_should_be_overwritten() {
+		WP_Interactivity_Initial_State::merge_state( 'core', array( 'a' => 1 ) );
+		WP_Interactivity_Initial_State::merge_state( 'core', array( 'a' => 'overwritten' ) );
+		$this->assertSame(
+			array(
+				'core' => array(
+					'a' => 'overwritten',
+				),
+			),
+			WP_Interactivity_Initial_State::get_data()
+		);
+	}
+
+	public function test_initial_state_existing_indexed_arrays_should_be_replaced() {
+		WP_Interactivity_Initial_State::merge_state( 'core', array( 'a' => array( 1, 2 ) ) );
+		WP_Interactivity_Initial_State::merge_state( 'core', array( 'a' => array( 3, 4 ) ) );
+		$this->assertSame(
+			array(
+				'core' => array(
+					'a' => array( 3, 4 ),
+				),
+			),
+			WP_Interactivity_Initial_State::get_data()
+		);
+	}
+
+	public function test_initial_state_should_be_correctly_rendered() {
+		WP_Interactivity_Initial_State::merge_state( 'core', array( 'a' => 1 ) );
+		WP_Interactivity_Initial_State::merge_state( 'core', array( 'b' => 2 ) );
+		WP_Interactivity_Initial_State::merge_state( 'custom', array( 'c' => 3 ) );
+
+		ob_start();
+		WP_Interactivity_Initial_State::render();
+		$rendered = ob_get_clean();
+		$this->assertSame(
+			'<script id="wp-interactivity-initial-state" type="application/json">{"core":{"a":1,"b":2},"custom":{"c":3}}</script>',
+			$rendered
+		);
+	}
+
+	public function test_initial_state_should_also_escape_tags_and_amps() {
+		WP_Interactivity_Initial_State::merge_state(
+			'test',
+			array(
+				'amps' => 'http://site.test/?foo=1&baz=2&bar=3',
+				'tags' => 'Do not do this: <!-- <script>',
+			)
+		);
+		ob_start();
+		WP_Interactivity_Initial_State::render();
+		$rendered = ob_get_clean();
+		$this->assertSame(
+			'<script id="wp-interactivity-initial-state" type="application/json">{"test":{"amps":"http:\/\/site.test\/?foo=1\u0026baz=2\u0026bar=3","tags":"Do not do this: \u003C!-- \u003Cscript\u003E"}}</script>',
+			$rendered
+		);
+	}
+}
diff --git a/phpunit/experimental/interactivity-api/class-wp-interactivity-store-test.php b/phpunit/experimental/interactivity-api/class-wp-interactivity-store-test.php
deleted file mode 100644
index 837d6fd50f193..0000000000000
--- a/phpunit/experimental/interactivity-api/class-wp-interactivity-store-test.php
+++ /dev/null
@@ -1,186 +0,0 @@
-<?php
-/**
- * `WP_Interactivity_Store` class test.
- *
- * @package Gutenberg
- * @subpackage Interactivity API
- */
-
-/**
- * Tests for the `WP_Interactivity_Store` class.
- *
- * @group  interactivity-api
- * @covers WP_Interactivity_Store
- */
-class WP_Interactivity_Store_Test extends WP_UnitTestCase {
-	public function set_up() {
-		// Clear the state before each test.
-		WP_Interactivity_Store::reset();
-	}
-
-	public function test_store_should_be_empty() {
-		$this->assertEmpty( WP_Interactivity_Store::get_data() );
-	}
-
-	public function test_store_can_be_merged() {
-		$data = array(
-			'state' => array(
-				'core' => array(
-					'a'      => 1,
-					'b'      => 2,
-					'nested' => array(
-						'c' => 3,
-					),
-				),
-			),
-		);
-		WP_Interactivity_Store::merge_data( $data );
-		$this->assertSame( $data, WP_Interactivity_Store::get_data() );
-	}
-
-	public function test_store_can_be_extended() {
-		WP_Interactivity_Store::merge_data(
-			array(
-				'state' => array(
-					'core' => array(
-						'a' => 1,
-					),
-				),
-			)
-		);
-		WP_Interactivity_Store::merge_data(
-			array(
-				'state' => array(
-					'core'   => array(
-						'b' => 2,
-					),
-					'custom' => array(
-						'c' => 3,
-					),
-				),
-			)
-		);
-		$this->assertSame(
-			array(
-				'state' => array(
-					'core'   => array(
-						'a' => 1,
-						'b' => 2,
-					),
-					'custom' => array(
-						'c' => 3,
-					),
-				),
-			),
-			WP_Interactivity_Store::get_data()
-		);
-	}
-
-	public function test_store_existing_props_should_be_overwritten() {
-		WP_Interactivity_Store::merge_data(
-			array(
-				'state' => array(
-					'core' => array(
-						'a' => 1,
-					),
-				),
-			)
-		);
-		WP_Interactivity_Store::merge_data(
-			array(
-				'state' => array(
-					'core' => array(
-						'a' => 'overwritten',
-					),
-				),
-			)
-		);
-		$this->assertSame(
-			array(
-				'state' => array(
-					'core' => array(
-						'a' => 'overwritten',
-					),
-				),
-			),
-			WP_Interactivity_Store::get_data()
-		);
-	}
-
-	public function test_store_existing_indexed_arrays_should_be_replaced() {
-		WP_Interactivity_Store::merge_data(
-			array(
-				'state' => array(
-					'core' => array(
-						'a' => array( 1, 2 ),
-					),
-				),
-			)
-		);
-		WP_Interactivity_Store::merge_data(
-			array(
-				'state' => array(
-					'core' => array(
-						'a' => array( 3, 4 ),
-					),
-				),
-			)
-		);
-		$this->assertSame(
-			array(
-				'state' => array(
-					'core' => array(
-						'a' => array( 3, 4 ),
-					),
-				),
-			),
-			WP_Interactivity_Store::get_data()
-		);
-	}
-
-	public function test_store_should_be_correctly_rendered() {
-		WP_Interactivity_Store::merge_data(
-			array(
-				'state' => array(
-					'core' => array(
-						'a' => 1,
-					),
-				),
-			)
-		);
-		WP_Interactivity_Store::merge_data(
-			array(
-				'state' => array(
-					'core' => array(
-						'b' => 2,
-					),
-				),
-			)
-		);
-		ob_start();
-		WP_Interactivity_Store::render();
-		$rendered = ob_get_clean();
-		$this->assertSame(
-			'<script id="wp-interactivity-initial-state" type="application/json">{"state":{"core":{"a":1,"b":2}}}</script>',
-			$rendered
-		);
-	}
-
-	public function test_store_should_also_escape_tags_and_amps() {
-		WP_Interactivity_Store::merge_data(
-			array(
-				'state' => array(
-					'amps' => 'http://site.test/?foo=1&baz=2&bar=3',
-					'tags' => 'Do not do this: <!-- <script>',
-				),
-			)
-		);
-		ob_start();
-		WP_Interactivity_Store::render();
-		$rendered = ob_get_clean();
-		$this->assertSame(
-			'<script id="wp-interactivity-initial-state" type="application/json">{"state":{"amps":"http:\/\/site.test\/?foo=1\u0026baz=2\u0026bar=3","tags":"Do not do this: \u003C!-- \u003Cscript\u003E"}}</script>',
-			$rendered
-		);
-	}
-}

From 5ae7d55f8fed86e0d35ae8c2ef225f77c2ecd970 Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Thu, 4 Jan 2024 17:00:41 +0100
Subject: [PATCH 08/20] Do not make namespace optional in `get_state()`

---
 .../class-wp-interactivity-initial-state.php                 | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/lib/experimental/interactivity-api/class-wp-interactivity-initial-state.php b/lib/experimental/interactivity-api/class-wp-interactivity-initial-state.php
index a1edbcff776fb..15e57edfa4a6a 100644
--- a/lib/experimental/interactivity-api/class-wp-interactivity-initial-state.php
+++ b/lib/experimental/interactivity-api/class-wp-interactivity-initial-state.php
@@ -32,10 +32,7 @@ class WP_Interactivity_Initial_State {
 	 *
 	 * @return array The requested state.
 	 */
-	public static function get_state( $store_ns = null ) {
-		if ( ! $store_ns ) {
-			return self::$initial_state;
-		}
+	public static function get_state( $store_ns ) {
 		return self::$initial_state[ $store_ns ] ?? array();
 	}
 

From daa7f124b64a766551ed94bb68f1c66c85bce94a Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Thu, 4 Jan 2024 17:28:41 +0100
Subject: [PATCH 09/20] Replace Store with Initial_State

---
 lib/experimental/interactivity-api/directive-processing.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/experimental/interactivity-api/directive-processing.php b/lib/experimental/interactivity-api/directive-processing.php
index 12269eab99b20..e4a551ce9555d 100644
--- a/lib/experimental/interactivity-api/directive-processing.php
+++ b/lib/experimental/interactivity-api/directive-processing.php
@@ -328,7 +328,7 @@ function gutenberg_interactivity_evaluate_reference( $reference, $ns, array $con
 	list( $ns, $path ) = WP_Directive_Processor::parse_attribute_value( $reference, $ns );
 
 	$store = array(
-		'state'   => WP_Interactivity_Store::get_data()[ $ns ],
+		'state'   => WP_Interactivity_Initial_State::get_state( $ns ),
 		'context' => $context[ $ns ] ?? array(),
 	);
 

From da9392cf037d2c644fa897abd549eec8593f5ef8 Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Thu, 4 Jan 2024 18:02:27 +0100
Subject: [PATCH 10/20] Fix set up and tear down of Initial State tests

---
 .../class-wp-interactivity-initial-state-test.php           | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/phpunit/experimental/interactivity-api/class-wp-interactivity-initial-state-test.php b/phpunit/experimental/interactivity-api/class-wp-interactivity-initial-state-test.php
index ece4ee9c39f01..a95c3482ec80d 100644
--- a/phpunit/experimental/interactivity-api/class-wp-interactivity-initial-state-test.php
+++ b/phpunit/experimental/interactivity-api/class-wp-interactivity-initial-state-test.php
@@ -14,9 +14,13 @@
  */
 class WP_Interactivity_Initial_State_Test extends WP_UnitTestCase {
 	public function set_up() {
-		// Clear the state before each test.
+		parent::set_up();
 		WP_Interactivity_Initial_State::reset();
 	}
+	public function tear_down() {
+		WP_Interactivity_Initial_State::reset();
+		parent::tear_down();
+	}
 
 	public function test_initial_state_should_be_empty() {
 		$this->assertEmpty( WP_Interactivity_Initial_State::get_data() );

From a6962cd1e746e73ff90635cd7102520518d048dd Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Thu, 4 Jan 2024 18:30:34 +0100
Subject: [PATCH 11/20] Update directive tests after implementation changes

---
 .../directives/wp-bind-test.php               | 12 ++--
 .../directives/wp-class-test.php              | 33 +++++-----
 .../directives/wp-context-test.php            | 61 ++++++++++---------
 .../directives/wp-style-test.php              | 12 ++--
 .../directives/wp-text-test.php               | 12 ++--
 5 files changed, 69 insertions(+), 61 deletions(-)

diff --git a/phpunit/experimental/interactivity-api/directives/wp-bind-test.php b/phpunit/experimental/interactivity-api/directives/wp-bind-test.php
index bfb4c428cd946..8fe212bb8ed93 100644
--- a/phpunit/experimental/interactivity-api/directives/wp-bind-test.php
+++ b/phpunit/experimental/interactivity-api/directives/wp-bind-test.php
@@ -14,16 +14,17 @@
  */
 class Tests_Directives_WpBind extends WP_UnitTestCase {
 	public function test_directive_sets_attribute() {
-		$markup = '<img data-wp-bind--src="context.myblock.imageSource" />';
+		$markup = '<img data-wp-bind--src="context.imageSource" />';
 		$tags   = new WP_HTML_Tag_Processor( $markup );
 		$tags->next_tag();
 
 		$context_before = new WP_Directive_Context( array( 'myblock' => array( 'imageSource' => './wordpress.png' ) ) );
 		$context        = $context_before;
-		gutenberg_interactivity_process_wp_bind( $tags, $context );
+		$directive_ns   = 'myblock';
+		gutenberg_interactivity_process_wp_bind( $tags, $context, $directive_ns );
 
 		$this->assertSame(
-			'<img src="./wordpress.png" data-wp-bind--src="context.myblock.imageSource" />',
+			'<img src="./wordpress.png" data-wp-bind--src="context.imageSource" />',
 			$tags->get_updated_html()
 		);
 		$this->assertSame( './wordpress.png', $tags->get_attribute( 'src' ) );
@@ -31,13 +32,14 @@ public function test_directive_sets_attribute() {
 	}
 
 	public function test_directive_ignores_empty_bound_attribute() {
-		$markup = '<img data-wp-bind.="context.myblock.imageSource" />';
+		$markup = '<img data-wp-bind.="context.imageSource" />';
 		$tags   = new WP_HTML_Tag_Processor( $markup );
 		$tags->next_tag();
 
 		$context_before = new WP_Directive_Context( array( 'myblock' => array( 'imageSource' => './wordpress.png' ) ) );
 		$context        = $context_before;
-		gutenberg_interactivity_process_wp_bind( $tags, $context );
+		$directive_ns   = 'myblock';
+		gutenberg_interactivity_process_wp_bind( $tags, $context, $directive_ns );
 
 		$this->assertSame( $markup, $tags->get_updated_html() );
 		$this->assertNull( $tags->get_attribute( 'src' ) );
diff --git a/phpunit/experimental/interactivity-api/directives/wp-class-test.php b/phpunit/experimental/interactivity-api/directives/wp-class-test.php
index 419546c6d9ef8..f40486647ff8b 100644
--- a/phpunit/experimental/interactivity-api/directives/wp-class-test.php
+++ b/phpunit/experimental/interactivity-api/directives/wp-class-test.php
@@ -14,16 +14,17 @@
  */
 class Tests_Directives_WpClass extends WP_UnitTestCase {
 	public function test_directive_adds_class() {
-		$markup = '<div data-wp-class--red="context.myblock.isRed" class="blue">Test</div>';
+		$markup = '<div data-wp-class--red="context.isRed" class="blue">Test</div>';
 		$tags   = new WP_HTML_Tag_Processor( $markup );
 		$tags->next_tag();
 
 		$context_before = new WP_Directive_Context( array( 'myblock' => array( 'isRed' => true ) ) );
 		$context        = $context_before;
-		gutenberg_interactivity_process_wp_class( $tags, $context );
+		$directive_ns   = 'myblock';
+		gutenberg_interactivity_process_wp_class( $tags, $context, $directive_ns );
 
 		$this->assertSame(
-			'<div data-wp-class--red="context.myblock.isRed" class="blue red">Test</div>',
+			'<div data-wp-class--red="context.isRed" class="blue red">Test</div>',
 			$tags->get_updated_html()
 		);
 		$this->assertStringContainsString( 'red', $tags->get_attribute( 'class' ) );
@@ -31,16 +32,17 @@ public function test_directive_adds_class() {
 	}
 
 	public function test_directive_removes_class() {
-		$markup = '<div data-wp-class--blue="context.myblock.isBlue" class="red blue">Test</div>';
+		$markup = '<div data-wp-class--blue="context.isBlue" class="red blue">Test</div>';
 		$tags   = new WP_HTML_Tag_Processor( $markup );
 		$tags->next_tag();
 
 		$context_before = new WP_Directive_Context( array( 'myblock' => array( 'isBlue' => false ) ) );
 		$context        = $context_before;
-		gutenberg_interactivity_process_wp_class( $tags, $context );
+		$directive_ns   = 'myblock';
+		gutenberg_interactivity_process_wp_class( $tags, $context, $directive_ns );
 
 		$this->assertSame(
-			'<div data-wp-class--blue="context.myblock.isBlue" class="red">Test</div>',
+			'<div data-wp-class--blue="context.isBlue" class="red">Test</div>',
 			$tags->get_updated_html()
 		);
 		$this->assertStringNotContainsString( 'blue', $tags->get_attribute( 'class' ) );
@@ -48,17 +50,18 @@ public function test_directive_removes_class() {
 	}
 
 	public function test_directive_removes_empty_class_attribute() {
-		$markup = '<div data-wp-class--blue="context.myblock.isBlue" class="blue">Test</div>';
+		$markup = '<div data-wp-class--blue="context.isBlue" class="blue">Test</div>';
 		$tags   = new WP_HTML_Tag_Processor( $markup );
 		$tags->next_tag();
 
 		$context_before = new WP_Directive_Context( array( 'myblock' => array( 'isBlue' => false ) ) );
 		$context        = $context_before;
-		gutenberg_interactivity_process_wp_class( $tags, $context );
+		$directive_ns   = 'myblock';
+		gutenberg_interactivity_process_wp_class( $tags, $context, $directive_ns );
 
 		$this->assertSame(
 			// WP_HTML_Tag_Processor has a TODO note to prune whitespace after classname removal.
-			'<div data-wp-class--blue="context.myblock.isBlue" >Test</div>',
+			'<div data-wp-class--blue="context.isBlue" >Test</div>',
 			$tags->get_updated_html()
 		);
 		$this->assertNull( $tags->get_attribute( 'class' ) );
@@ -66,16 +69,17 @@ public function test_directive_removes_empty_class_attribute() {
 	}
 
 	public function test_directive_does_not_remove_non_existant_class() {
-		$markup = '<div data-wp-class--blue="context.myblock.isBlue" class="green red">Test</div>';
+		$markup = '<div data-wp-class--blue="context.isBlue" class="green red">Test</div>';
 		$tags   = new WP_HTML_Tag_Processor( $markup );
 		$tags->next_tag();
 
 		$context_before = new WP_Directive_Context( array( 'myblock' => array( 'isBlue' => false ) ) );
 		$context        = $context_before;
-		gutenberg_interactivity_process_wp_class( $tags, $context );
+		$directive_ns   = 'myblock';
+		gutenberg_interactivity_process_wp_class( $tags, $context, $directive_ns );
 
 		$this->assertSame(
-			'<div data-wp-class--blue="context.myblock.isBlue" class="green red">Test</div>',
+			'<div data-wp-class--blue="context.isBlue" class="green red">Test</div>',
 			$tags->get_updated_html()
 		);
 		$this->assertSame( 'green red', $tags->get_attribute( 'class' ) );
@@ -83,13 +87,14 @@ public function test_directive_does_not_remove_non_existant_class() {
 	}
 
 	public function test_directive_ignores_empty_class_name() {
-		$markup = '<div data-wp-class.="context.myblock.isRed" class="blue">Test</div>';
+		$markup = '<div data-wp-class.="context.isRed" class="blue">Test</div>';
 		$tags   = new WP_HTML_Tag_Processor( $markup );
 		$tags->next_tag();
 
 		$context_before = new WP_Directive_Context( array( 'myblock' => array( 'isRed' => true ) ) );
 		$context        = $context_before;
-		gutenberg_interactivity_process_wp_class( $tags, $context );
+		$directive_ns   = 'myblock';
+		gutenberg_interactivity_process_wp_class( $tags, $context, $directive_ns );
 
 		$this->assertSame( $markup, $tags->get_updated_html() );
 		$this->assertStringNotContainsString( 'red', $tags->get_attribute( 'class' ) );
diff --git a/phpunit/experimental/interactivity-api/directives/wp-context-test.php b/phpunit/experimental/interactivity-api/directives/wp-context-test.php
index 1277b016848cc..788feec95fe7c 100644
--- a/phpunit/experimental/interactivity-api/directives/wp-context-test.php
+++ b/phpunit/experimental/interactivity-api/directives/wp-context-test.php
@@ -21,11 +21,12 @@ public function test_directive_merges_context_correctly_upon_wp_context_attribut
 			)
 		);
 
-		$markup = '<div data-wp-context=\'{ "myblock": { "open": true } }\'>';
+		$ns     = 'myblock';
+		$markup = '<div data-wp-context=\'{ "open": true }\'>';
 		$tags   = new WP_HTML_Tag_Processor( $markup );
 		$tags->next_tag();
 
-		gutenberg_interactivity_process_wp_context( $tags, $context );
+		gutenberg_interactivity_process_wp_context( $tags, $context, $ns );
 
 		$this->assertSame(
 			array(
@@ -38,39 +39,39 @@ public function test_directive_merges_context_correctly_upon_wp_context_attribut
 
 	public function test_directive_resets_context_correctly_upon_closing_tag() {
 		$context = new WP_Directive_Context(
-			array( 'my-key' => 'original-value' )
+			array( 'myblock' => array( 'my-key' => 'original-value' ) )
 		);
 
 		$context->set_context(
-			array( 'my-key' => 'new-value' )
+			array( 'myblock' => array( 'my-key' => 'new-value' ) )
 		);
 
 		$markup = '</div>';
 		$tags   = new WP_HTML_Tag_Processor( $markup );
 		$tags->next_tag( array( 'tag_closers' => 'visit' ) );
 
-		gutenberg_interactivity_process_wp_context( $tags, $context );
+		gutenberg_interactivity_process_wp_context( $tags, $context, 'myblock' );
 
 		$this->assertSame(
 			array( 'my-key' => 'original-value' ),
-			$context->get_context()
+			$context->get_context()['myblock']
 		);
 	}
 
 	public function test_directive_doesnt_throw_on_malformed_context_objects() {
 		$context = new WP_Directive_Context(
-			array( 'my-key' => 'some-value' )
+			array( 'myblock' => array( 'my-key' => 'some-value' ) )
 		);
 
 		$markup = '<div data-wp-context=\'{ "wrong_json_object: }\'>';
 		$tags   = new WP_HTML_Tag_Processor( $markup );
 		$tags->next_tag();
 
-		gutenberg_interactivity_process_wp_context( $tags, $context );
+		gutenberg_interactivity_process_wp_context( $tags, $context, 'myblock' );
 
 		$this->assertSame(
 			array( 'my-key' => 'some-value' ),
-			$context->get_context()
+			$context->get_context()['myblock']
 		);
 	}
 
@@ -87,36 +88,36 @@ public function test_directive_keeps_working_after_malformed_context_objects() {
 
 		// Parent div.
 		$tags->next_tag( array( 'tag_closers' => 'visit' ) );
-		gutenberg_interactivity_process_wp_context( $tags, $context );
+		gutenberg_interactivity_process_wp_context( $tags, $context, 'myblock' );
 
 		$this->assertSame(
 			array( 'my-key' => 'some-value' ),
-			$context->get_context()
+			$context->get_context()['myblock']
 		);
 
 		// Children div.
 		$tags->next_tag( array( 'tag_closers' => 'visit' ) );
-		gutenberg_interactivity_process_wp_context( $tags, $context );
+		gutenberg_interactivity_process_wp_context( $tags, $context, 'myblock' );
 
 		// Still the same context.
 		$this->assertSame(
 			array( 'my-key' => 'some-value' ),
-			$context->get_context()
+			$context->get_context()['myblock']
 		);
 
 		// Closing children div.
 		$tags->next_tag( array( 'tag_closers' => 'visit' ) );
-		gutenberg_interactivity_process_wp_context( $tags, $context );
+		gutenberg_interactivity_process_wp_context( $tags, $context, 'myblock' );
 
 		// Still the same context.
 		$this->assertSame(
 			array( 'my-key' => 'some-value' ),
-			$context->get_context()
+			$context->get_context()['myblock']
 		);
 
 		// Closing parent div.
 		$tags->next_tag( array( 'tag_closers' => 'visit' ) );
-		gutenberg_interactivity_process_wp_context( $tags, $context );
+		gutenberg_interactivity_process_wp_context( $tags, $context, 'myblock' );
 
 		// Now the context is empty.
 		$this->assertSame(
@@ -138,36 +139,36 @@ public function test_directive_keeps_working_with_a_directive_without_value() {
 
 		// Parent div.
 		$tags->next_tag( array( 'tag_closers' => 'visit' ) );
-		gutenberg_interactivity_process_wp_context( $tags, $context );
+		gutenberg_interactivity_process_wp_context( $tags, $context, 'myblock' );
 
 		$this->assertSame(
 			array( 'my-key' => 'some-value' ),
-			$context->get_context()
+			$context->get_context()['myblock']
 		);
 
 		// Children div.
 		$tags->next_tag( array( 'tag_closers' => 'visit' ) );
-		gutenberg_interactivity_process_wp_context( $tags, $context );
+		gutenberg_interactivity_process_wp_context( $tags, $context, 'myblock' );
 
 		// Still the same context.
 		$this->assertSame(
 			array( 'my-key' => 'some-value' ),
-			$context->get_context()
+			$context->get_context()['myblock']
 		);
 
 		// Closing children div.
 		$tags->next_tag( array( 'tag_closers' => 'visit' ) );
-		gutenberg_interactivity_process_wp_context( $tags, $context );
+		gutenberg_interactivity_process_wp_context( $tags, $context, 'myblock' );
 
 		// Still the same context.
 		$this->assertSame(
 			array( 'my-key' => 'some-value' ),
-			$context->get_context()
+			$context->get_context()['myblock']
 		);
 
 		// Closing parent div.
 		$tags->next_tag( array( 'tag_closers' => 'visit' ) );
-		gutenberg_interactivity_process_wp_context( $tags, $context );
+		gutenberg_interactivity_process_wp_context( $tags, $context, 'myblock' );
 
 		// Now the context is empty.
 		$this->assertSame(
@@ -189,36 +190,36 @@ public function test_directive_keeps_working_with_an_empty_directive() {
 
 		// Parent div.
 		$tags->next_tag( array( 'tag_closers' => 'visit' ) );
-		gutenberg_interactivity_process_wp_context( $tags, $context );
+		gutenberg_interactivity_process_wp_context( $tags, $context, 'myblock' );
 
 		$this->assertSame(
 			array( 'my-key' => 'some-value' ),
-			$context->get_context()
+			$context->get_context()['myblock']
 		);
 
 		// Children div.
 		$tags->next_tag( array( 'tag_closers' => 'visit' ) );
-		gutenberg_interactivity_process_wp_context( $tags, $context );
+		gutenberg_interactivity_process_wp_context( $tags, $context, 'myblock' );
 
 		// Still the same context.
 		$this->assertSame(
 			array( 'my-key' => 'some-value' ),
-			$context->get_context()
+			$context->get_context()['myblock']
 		);
 
 		// Closing children div.
 		$tags->next_tag( array( 'tag_closers' => 'visit' ) );
-		gutenberg_interactivity_process_wp_context( $tags, $context );
+		gutenberg_interactivity_process_wp_context( $tags, $context, 'myblock' );
 
 		// Still the same context.
 		$this->assertSame(
 			array( 'my-key' => 'some-value' ),
-			$context->get_context()
+			$context->get_context()['myblock']
 		);
 
 		// Closing parent div.
 		$tags->next_tag( array( 'tag_closers' => 'visit' ) );
-		gutenberg_interactivity_process_wp_context( $tags, $context );
+		gutenberg_interactivity_process_wp_context( $tags, $context, 'myblock' );
 
 		// Now the context is empty.
 		$this->assertSame(
diff --git a/phpunit/experimental/interactivity-api/directives/wp-style-test.php b/phpunit/experimental/interactivity-api/directives/wp-style-test.php
index 51468bd8a2814..9625803ebca78 100644
--- a/phpunit/experimental/interactivity-api/directives/wp-style-test.php
+++ b/phpunit/experimental/interactivity-api/directives/wp-style-test.php
@@ -18,9 +18,9 @@ public function test_directive_adds_style() {
 		$tags   = new WP_HTML_Tag_Processor( $markup );
 		$tags->next_tag();
 
-		$context_before = new WP_Directive_Context( array( 'color' => 'green' ) );
+		$context_before = new WP_Directive_Context( array( 'myblock' => array( 'color' => 'green' ) ) );
 		$context        = $context_before;
-		gutenberg_interactivity_process_wp_style( $tags, $context );
+		gutenberg_interactivity_process_wp_style( $tags, $context, 'myblock' );
 
 		$this->assertSame(
 			'<div data-wp-style--color="context.color" style="background: blue;color: green;">Test</div>',
@@ -35,9 +35,9 @@ public function test_directive_ignores_empty_style() {
 		$tags   = new WP_HTML_Tag_Processor( $markup );
 		$tags->next_tag();
 
-		$context_before = new WP_Directive_Context( array( 'color' => 'green' ) );
+		$context_before = new WP_Directive_Context( array( 'myblock' => array( 'color' => 'green' ) ) );
 		$context        = $context_before;
-		gutenberg_interactivity_process_wp_style( $tags, $context );
+		gutenberg_interactivity_process_wp_style( $tags, $context, 'myblock' );
 
 		$this->assertSame( $markup, $tags->get_updated_html() );
 		$this->assertStringNotContainsString( 'color: green;', $tags->get_attribute( 'style' ) );
@@ -49,9 +49,9 @@ public function test_directive_works_without_style_attribute() {
 		$tags   = new WP_HTML_Tag_Processor( $markup );
 		$tags->next_tag();
 
-		$context_before = new WP_Directive_Context( array( 'color' => 'green' ) );
+		$context_before = new WP_Directive_Context( array( 'myblock' => array( 'color' => 'green' ) ) );
 		$context        = $context_before;
-		gutenberg_interactivity_process_wp_style( $tags, $context );
+		gutenberg_interactivity_process_wp_style( $tags, $context, 'myblock' );
 
 		$this->assertSame(
 			'<div style="color: green;" data-wp-style--color="context.color">Test</div>',
diff --git a/phpunit/experimental/interactivity-api/directives/wp-text-test.php b/phpunit/experimental/interactivity-api/directives/wp-text-test.php
index 81d2d0f370a64..9c889a3f0eb68 100644
--- a/phpunit/experimental/interactivity-api/directives/wp-text-test.php
+++ b/phpunit/experimental/interactivity-api/directives/wp-text-test.php
@@ -14,31 +14,31 @@
  */
 class Tests_Directives_WpText extends WP_UnitTestCase {
 	public function test_directive_sets_inner_html_based_on_attribute_value_and_escapes_html() {
-		$markup = '<div data-wp-text="context.myblock.someText"></div>';
+		$markup = '<div data-wp-text="context.someText"></div>';
 
 		$tags = new WP_Directive_Processor( $markup );
 		$tags->next_tag();
 
 		$context_before = new WP_Directive_Context( array( 'myblock' => array( 'someText' => 'The HTML tag <br> produces a line break.' ) ) );
 		$context        = clone $context_before;
-		gutenberg_interactivity_process_wp_text( $tags, $context );
+		gutenberg_interactivity_process_wp_text( $tags, $context, 'myblock' );
 
-		$expected_markup = '<div data-wp-text="context.myblock.someText">The HTML tag &lt;br&gt; produces a line break.</div>';
+		$expected_markup = '<div data-wp-text="context.someText">The HTML tag &lt;br&gt; produces a line break.</div>';
 		$this->assertSame( $expected_markup, $tags->get_updated_html() );
 		$this->assertSame( $context_before->get_context(), $context->get_context(), 'data-wp-text directive changed context' );
 	}
 
 	public function test_directive_overwrites_inner_html_based_on_attribute_value() {
-		$markup = '<div data-wp-text="context.myblock.someText">Lorem ipsum dolor sit.</div>';
+		$markup = '<div data-wp-text="context.someText">Lorem ipsum dolor sit.</div>';
 
 		$tags = new WP_Directive_Processor( $markup );
 		$tags->next_tag();
 
 		$context_before = new WP_Directive_Context( array( 'myblock' => array( 'someText' => 'Honi soit qui mal y pense.' ) ) );
 		$context        = clone $context_before;
-		gutenberg_interactivity_process_wp_text( $tags, $context );
+		gutenberg_interactivity_process_wp_text( $tags, $context, 'myblock' );
 
-		$expected_markup = '<div data-wp-text="context.myblock.someText">Honi soit qui mal y pense.</div>';
+		$expected_markup = '<div data-wp-text="context.someText">Honi soit qui mal y pense.</div>';
 		$this->assertSame( $expected_markup, $tags->get_updated_html() );
 		$this->assertSame( $context_before->get_context(), $context->get_context(), 'data-wp-text directive changed context' );
 	}

From 8398252b0b79a69450bc1e095cfa6da0ef097914 Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Thu, 4 Jan 2024 18:51:26 +0100
Subject: [PATCH 12/20] Add TODO comment to derived state

---
 lib/experimental/interactivity-api/directive-processing.php | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/experimental/interactivity-api/directive-processing.php b/lib/experimental/interactivity-api/directive-processing.php
index e4a551ce9555d..40526ebfcd70a 100644
--- a/lib/experimental/interactivity-api/directive-processing.php
+++ b/lib/experimental/interactivity-api/directive-processing.php
@@ -358,6 +358,8 @@ function gutenberg_interactivity_evaluate_reference( $reference, $ns, array $con
 	 * E.g., "file" is an string and a "callable" (the "file" function exists).
 	 */
 	if ( $current instanceof Closure ) {
+		// TODO: Do not pass the store as argument. Implement something similar
+		// to what we have in the JS runtime (`getContext()`, etc.).
 		$current = call_user_func( $current, $store );
 	}
 

From 5f333ffbed73fb116eaea67fb31f112bfd7f65f9 Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Thu, 4 Jan 2024 18:56:16 +0100
Subject: [PATCH 13/20] Refactor directive processing tests

---
 .../directive-processing-test.php             | 88 ++++++++++---------
 1 file changed, 47 insertions(+), 41 deletions(-)

diff --git a/phpunit/experimental/interactivity-api/directive-processing-test.php b/phpunit/experimental/interactivity-api/directive-processing-test.php
index 99218f69a8fb7..efbe307043a9f 100644
--- a/phpunit/experimental/interactivity-api/directive-processing-test.php
+++ b/phpunit/experimental/interactivity-api/directive-processing-test.php
@@ -85,6 +85,7 @@ public function set_up() {
 	}
 
 	public function tear_down() {
+		WP_Interactivity_Initial_State::reset();
 		unregister_block_type( 'test/context-level-1' );
 		unregister_block_type( 'test/context-level-2' );
 		unregister_block_type( 'test/context-read-only' );
@@ -228,29 +229,37 @@ public function test_directives_ordering() {
 
 	public function test_evaluate_function_should_access_state() {
 		// Init a simple store.
-		wp_store(
+		wp_initial_state(
+			'test',
 			array(
-				'state' => array(
-					'core' => array(
-						'number' => 1,
-						'bool'   => true,
-						'nested' => array(
-							'string' => 'hi',
-						),
-					),
+				'number' => 1,
+				'bool'   => true,
+				'nested' => array(
+					'string' => 'hi',
 				),
 			)
 		);
 
-		$this->assertSame( 1, gutenberg_interactivity_evaluate_reference( 'state.core.number' ) );
-		$this->assertTrue( gutenberg_interactivity_evaluate_reference( 'state.core.bool' ) );
-		$this->assertSame( 'hi', gutenberg_interactivity_evaluate_reference( 'state.core.nested.string' ) );
-		$this->assertFalse( gutenberg_interactivity_evaluate_reference( '!state.core.bool' ) );
+		$this->assertSame( 1, gutenberg_interactivity_evaluate_reference( 'state.number', 'test' ) );
+		$this->assertTrue( gutenberg_interactivity_evaluate_reference( 'state.bool', 'test' ) );
+		$this->assertSame( 'hi', gutenberg_interactivity_evaluate_reference( 'state.nested.string', 'test' ) );
+		$this->assertFalse( gutenberg_interactivity_evaluate_reference( '!state.bool', 'test' ) );
 	}
 
 	public function test_evaluate_function_should_access_passed_context() {
+		wp_initial_state(
+			'test',
+			array(
+				'number' => 1,
+				'bool'   => true,
+				'nested' => array(
+					'string' => 'hi',
+				),
+			)
+		);
+
 		$context = array(
-			'local' => array(
+			'test' => array(
 				'number' => 2,
 				'bool'   => false,
 				'nested' => array(
@@ -259,53 +268,50 @@ public function test_evaluate_function_should_access_passed_context() {
 			),
 		);
 
-		$this->assertSame( 2, gutenberg_interactivity_evaluate_reference( 'context.local.number', $context ) );
-		$this->assertFalse( gutenberg_interactivity_evaluate_reference( 'context.local.bool', $context ) );
-		$this->assertTrue( gutenberg_interactivity_evaluate_reference( '!context.local.bool', $context ) );
-		$this->assertSame( 'bye', gutenberg_interactivity_evaluate_reference( 'context.local.nested.string', $context ) );
+		$this->assertSame( 2, gutenberg_interactivity_evaluate_reference( 'context.number', 'test', $context ) );
+		$this->assertFalse( gutenberg_interactivity_evaluate_reference( 'context.bool', 'test', $context ) );
+		$this->assertTrue( gutenberg_interactivity_evaluate_reference( '!context.bool', 'test', $context ) );
+		$this->assertSame( 'bye', gutenberg_interactivity_evaluate_reference( 'context.nested.string', 'test', $context ) );
 
-		// Previously defined state is also accessible.
-		$this->assertSame( 1, gutenberg_interactivity_evaluate_reference( 'state.core.number' ) );
-		$this->assertTrue( gutenberg_interactivity_evaluate_reference( 'state.core.bool' ) );
-		$this->assertSame( 'hi', gutenberg_interactivity_evaluate_reference( 'state.core.nested.string' ) );
+		// Defined state is also accessible.
+		$this->assertSame( 1, gutenberg_interactivity_evaluate_reference( 'state.number', 'test' ) );
+		$this->assertTrue( gutenberg_interactivity_evaluate_reference( 'state.bool', 'test' ) );
+		$this->assertSame( 'hi', gutenberg_interactivity_evaluate_reference( 'state.nested.string', 'test' ) );
 	}
 
 	public function test_evaluate_function_should_return_null_for_unresolved_paths() {
-		$this->assertNull( gutenberg_interactivity_evaluate_reference( 'this.property.doesnt.exist' ) );
+		$this->assertNull( gutenberg_interactivity_evaluate_reference( 'this.property.doesnt.exist', 'myblock' ) );
 	}
 
 	public function test_evaluate_function_should_execute_anonymous_functions() {
-		$context = new WP_Directive_Context( array( 'count' => 2 ) );
+		$context = new WP_Directive_Context( array( 'myblock' => array( 'count' => 2 ) ) );
 
-		wp_store(
+		wp_initial_state(
+			'myblock',
 			array(
-				'state'     => array(
-					'count' => 3,
-				),
-				'selectors' => array(
-					'anonymous_function'  => function ( $store ) {
-						return $store['state']['count'] + $store['context']['count'];
-					},
-					// Other types of callables should not be executed.
-					'function_name'       => 'gutenberg_test_process_directives_helper_increment',
-					'class_method'        => array( $this, 'increment' ),
-					'class_static_method' => array( 'Tests_Process_Directives', 'static_increment' ),
-				),
+				'count'               => 3,
+				'anonymous_function'  => function ( $store ) {
+					return $store['state']['count'] + $store['context']['count'];
+				},
+				// Other types of callables should not be executed.
+				'function_name'       => 'gutenberg_test_process_directives_helper_increment',
+				'class_method'        => array( $this, 'increment' ),
+				'class_static_method' => array( 'Tests_Process_Directives', 'static_increment' ),
 			)
 		);
 
-		$this->assertSame( 5, gutenberg_interactivity_evaluate_reference( 'selectors.anonymous_function', $context->get_context() ) );
+		$this->assertSame( 5, gutenberg_interactivity_evaluate_reference( 'state.anonymous_function', 'myblock', $context->get_context() ) );
 		$this->assertSame(
 			'gutenberg_test_process_directives_helper_increment',
-			gutenberg_interactivity_evaluate_reference( 'selectors.function_name', $context->get_context() )
+			gutenberg_interactivity_evaluate_reference( 'state.function_name', 'myblock', $context->get_context() )
 		);
 		$this->assertSame(
 			array( $this, 'increment' ),
-			gutenberg_interactivity_evaluate_reference( 'selectors.class_method', $context->get_context() )
+			gutenberg_interactivity_evaluate_reference( 'state.class_method', 'myblock', $context->get_context() )
 		);
 		$this->assertSame(
 			array( 'Tests_Process_Directives', 'static_increment' ),
-			gutenberg_interactivity_evaluate_reference( 'selectors.class_static_method', $context->get_context() )
+			gutenberg_interactivity_evaluate_reference( 'state.class_static_method', 'myblock', $context->get_context() )
 		);
 	}
 }

From 640e72344e17bf26fb01d746d6d5874f7ddfcdb7 Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Tue, 9 Jan 2024 15:16:13 +0100
Subject: [PATCH 14/20] Move namespace logic to a directive

---
 .../directive-processing.php                  | 34 ++++++---------
 .../directives/wp-interactive.php             | 42 +++++++++++++++++++
 lib/load.php                                  |  1 +
 3 files changed, 56 insertions(+), 21 deletions(-)
 create mode 100644 lib/experimental/interactivity-api/directives/wp-interactive.php

diff --git a/lib/experimental/interactivity-api/directive-processing.php b/lib/experimental/interactivity-api/directive-processing.php
index 40526ebfcd70a..80d5ee71815da 100644
--- a/lib/experimental/interactivity-api/directive-processing.php
+++ b/lib/experimental/interactivity-api/directive-processing.php
@@ -193,11 +193,12 @@ function gutenberg_process_non_interactive_block( $non_interactive_block, $conte
  */
 function gutenberg_process_interactive_html( $html, $context, $inner_blocks = array(), &$namespace_stack = array() ) {
 	static $directives = array(
-		'data-wp-context' => 'gutenberg_interactivity_process_wp_context',
-		'data-wp-bind'    => 'gutenberg_interactivity_process_wp_bind',
-		'data-wp-class'   => 'gutenberg_interactivity_process_wp_class',
-		'data-wp-style'   => 'gutenberg_interactivity_process_wp_style',
-		'data-wp-text'    => 'gutenberg_interactivity_process_wp_text',
+		'data-wp-interactive' => 'gutenberg_interactivity_process_wp_interactive',
+		'data-wp-context'     => 'gutenberg_interactivity_process_wp_context',
+		'data-wp-bind'        => 'gutenberg_interactivity_process_wp_bind',
+		'data-wp-class'       => 'gutenberg_interactivity_process_wp_class',
+		'data-wp-style'       => 'gutenberg_interactivity_process_wp_style',
+		'data-wp-text'        => 'gutenberg_interactivity_process_wp_text',
 	);
 
 	$tags                   = new WP_Directive_Processor( $html );
@@ -273,26 +274,17 @@ function gutenberg_process_interactive_html( $html, $context, $inner_blocks = ar
 			$attributes
 		);
 
-		// Push the new namespace if the current tag is an island.
-		$island = $tags->get_attribute( 'data-wp-interactive' );
-		if ( isset( $island ) && ! $tags->is_tag_closer() ) {
-			$island_data       = json_decode( $island, true );
-			$namespace_stack[] = $island_data['namespace'];
-		}
-
 		foreach ( $sorted_attrs as $attribute ) {
-			call_user_func(
+			call_user_func_array(
 				$directives[ $attribute ],
-				$tags,
-				$context,
-				end( $namespace_stack )
+				array(
+					$tags,
+					$context,
+					end( $namespace_stack ),
+					&$namespace_stack,
+				)
 			);
 		}
-
-		// Pop the current namespace if this is the closing tag of an island.
-		if ( isset( $island ) && $tags->is_tag_closer() ) {
-			array_pop( $namespace_stack );
-		}
 	}
 
 	$processed_html = $tags->get_updated_html();
diff --git a/lib/experimental/interactivity-api/directives/wp-interactive.php b/lib/experimental/interactivity-api/directives/wp-interactive.php
new file mode 100644
index 0000000000000..72a0f70274562
--- /dev/null
+++ b/lib/experimental/interactivity-api/directives/wp-interactive.php
@@ -0,0 +1,42 @@
+<?php
+/**
+ * Process the wp-interactive directive.
+ *
+ * @package Gutenberg
+ * @subpackage Interactivity API
+ */
+
+/**
+ * Process wp-interactive directive.
+ *
+ * @param WP_Directive_Processor $tags Tags.
+ * @param WP_Directive_Context   $context Directive context.
+ * @param string                 $ns Namespace.
+ * @param array                  $ns_stack Namespace stack.
+ */
+function gutenberg_interactivity_process_wp_interactive( $tags, $context, $ns, &$ns_stack ) {
+	// Pop the current namespace if this is the closing tag of an island.
+	if ( $tags->is_tag_closer() ) {
+		array_pop( $ns_stack );
+		return;
+	}
+
+	/*
+	 * Decode the data-wp-interactive attribute. In the case it is not a valid
+	 * JSON string, the NULL value is stored in `$island_data`.
+	 */
+	$island      = $tags->get_attribute( 'data-wp-interactive' );
+	$island_data = json_decode( $island, true );
+
+	/*
+	 * Push the newly defined namespace, or the current one if the island
+	 * definition was invalid or does not contain a namespace.
+	 *
+	 * This is done because the function pops out the current namespace from the
+	 * stack whenever it finds an island's closing tag, independtly of whether
+	 * the island definition was correct or contained a valid namespace.
+	 */
+	$ns_stack[] = isset( $island_data ) && $island_data['namespace']
+		? $island_data['namespace']
+		: $ns;
+}
diff --git a/lib/load.php b/lib/load.php
index f8335a141e57f..d413334227ee7 100644
--- a/lib/load.php
+++ b/lib/load.php
@@ -128,6 +128,7 @@ function gutenberg_is_experiment_enabled( $name ) {
 require __DIR__ . '/experimental/interactivity-api/directives/wp-class.php';
 require __DIR__ . '/experimental/interactivity-api/directives/wp-style.php';
 require __DIR__ . '/experimental/interactivity-api/directives/wp-text.php';
+require __DIR__ . '/experimental/interactivity-api/directives/wp-interactive.php';
 
 require __DIR__ . '/experimental/modules/class-gutenberg-modules.php';
 

From a7da3a9a789b2da469d13dfe530900f5c264188e Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Tue, 9 Jan 2024 15:33:41 +0100
Subject: [PATCH 15/20] Add tests for namespaces logic

---
 .../directive-processing-test.php             | 205 ++++++++++++++++++
 1 file changed, 205 insertions(+)

diff --git a/phpunit/experimental/interactivity-api/directive-processing-test.php b/phpunit/experimental/interactivity-api/directive-processing-test.php
index efbe307043a9f..4b7ca71a64c90 100644
--- a/phpunit/experimental/interactivity-api/directive-processing-test.php
+++ b/phpunit/experimental/interactivity-api/directive-processing-test.php
@@ -82,6 +82,31 @@ public function set_up() {
 				),
 			)
 		);
+
+		register_block_type(
+			'test/directives',
+			array(
+				'render_callback' => function ( $attributes, $content ) {
+					$parsed_attributes = array();
+					foreach ( $attributes as $key => $value ) {
+						$parsed_attributes[ $key ] = is_array( $value )
+							? wp_json_encode( $value, JSON_HEX_APOS )
+							: esc_attr( $value );
+					}
+
+					$wrapper_attributes = get_block_wrapper_attributes(
+						$parsed_attributes
+					);
+
+					return "<div $wrapper_attributes>$content</div>";
+				},
+				'supports'        => array(
+					'interactivity' => true,
+				),
+			)
+		);
+
+		WP_Interactivity_Initial_State::reset();
 	}
 
 	public function tear_down() {
@@ -92,6 +117,7 @@ public function tear_down() {
 		unregister_block_type( 'test/non-interactive-with-directive' );
 		unregister_block_type( 'test/context-level-with-manual-inner-block-rendering' );
 		unregister_block_type( 'test/directives-ordering' );
+		unregister_block_type( 'test/directives' );
 		parent::tear_down();
 	}
 
@@ -314,4 +340,183 @@ public function test_evaluate_function_should_execute_anonymous_functions() {
 			gutenberg_interactivity_evaluate_reference( 'state.class_static_method', 'myblock', $context->get_context() )
 		);
 	}
+
+	public function test_namespace_should_be_inherited_from_ancestor() {
+		/*
+		 * This function call should be done inside block render functions. We
+		 * run it here instead just for conveninence.
+		 */
+		wp_initial_state( 'test-1', array( 'text' => 'state' ) );
+
+		$post_content = '
+			<!-- wp:test/directives { "data-wp-interactive": { "namespace": "test-1" } } -->
+				<!-- wp:test/directives { "data-wp-context": { "text": "context" } } -->
+					<!-- wp:test/directives {
+						"class": "bind-state",
+						"data-wp-bind--data-value": "state.text"
+					} /-->
+					<!-- wp:test/directives {
+						"class": "bind-context",
+						"data-wp-bind--data-value": "context.text"
+					} /-->
+				<!-- /wp:test/directives -->
+			<!-- /wp:test/directives -->
+		';
+
+		$html = do_blocks( $post_content );
+		$tags = new WP_HTML_Tag_Processor( $html );
+
+		$tags->next_tag( array( 'class_name' => 'bind-state' ) );
+		$this->assertSame( 'state', $tags->get_attribute( 'data-value' ) );
+
+		$tags->next_tag( array( 'class_name' => 'bind-context' ) );
+		$this->assertSame( 'context', $tags->get_attribute( 'data-value' ) );
+	}
+
+	public function test_namespace_should_be_inherited_from_same_element() {
+		/*
+		 * This function call should be done inside block render functions. We
+		 * run it here instead just for conveninence.
+		 */
+		wp_initial_state( 'test-2', array( 'text' => 'state-2' ) );
+
+		$post_content = '
+			<!-- wp:test/directives { "data-wp-interactive": { "namespace": "test-1" } } -->
+				<!-- wp:test/directives { "data-wp-context": { "text": "context" } } -->
+					<!-- wp:test/directives {
+						"class": "bind-state",
+						"data-wp-interactive": { "namespace": "test-2" },
+						"data-wp-bind--data-value": "state.text"
+					} /-->
+					<!-- wp:test/directives {
+						"class": "bind-context",
+						"data-wp-interactive": { "namespace": "test-2" },
+						"data-wp-context": { "text": "context-2" },
+						"data-wp-bind--data-value": "context.text"
+					} /-->
+				<!-- /wp:test/directives -->
+			<!-- /wp:test/directives -->
+		';
+
+		$html = do_blocks( $post_content );
+		$tags = new WP_HTML_Tag_Processor( $html );
+
+		$tags->next_tag( array( 'class_name' => 'bind-state' ) );
+		$this->assertSame( 'state-2', $tags->get_attribute( 'data-value' ) );
+
+		$tags->next_tag( array( 'class_name' => 'bind-context' ) );
+		$this->assertSame( 'context-2', $tags->get_attribute( 'data-value' ) );
+	}
+
+	public function test_namespace_should_not_leak_from_descendant() {
+		/*
+		 * This function call should be done inside block render functions. We
+		 * run it here instead just for conveninence.
+		 */
+		wp_initial_state( 'test-1', array( 'text' => 'state-1' ) );
+		wp_initial_state( 'test-2', array( 'text' => 'state-2' ) );
+
+		$post_content = '
+			<!-- wp:test/directives {
+				"data-wp-interactive": { "namespace": "test-2" },
+				"data-wp-context": { "text": "context-2" }
+			} -->
+				<!-- wp:test/directives {
+					"class": "target",
+					"data-wp-interactive": { "namespace": "test-1" },
+					"data-wp-context": { "text": "context-1" },
+					"data-wp-bind--data-state": "state.text",
+					"data-wp-bind--data-context": "context.text"
+				} -->
+					<!-- wp:test/directives {
+						"data-wp-interactive": { "namespace": "test-2" }
+					} /-->
+				<!-- /wp:test/directives -->
+			<!-- /wp:test/directives -->
+		';
+
+		$html = do_blocks( $post_content );
+		$tags = new WP_HTML_Tag_Processor( $html );
+
+		$tags->next_tag( array( 'class_name' => 'target' ) );
+		$this->assertSame( 'state-1', $tags->get_attribute( 'data-state' ) );
+		$this->assertSame( 'context-1', $tags->get_attribute( 'data-context' ) );
+	}
+
+	public function test_namespace_should_not_leak_from_sibling() {
+		/*
+		 * This function call should be done inside block render functions. We
+		 * run it here instead just for conveninence.
+		 */
+		wp_initial_state( 'test-1', array( 'text' => 'state-1' ) );
+		wp_initial_state( 'test-2', array( 'text' => 'state-2' ) );
+
+		$post_content = '
+			<!-- wp:test/directives {
+				"data-wp-interactive": { "namespace": "test-2" },
+				"data-wp-context": { "text": "context-2" }
+			} -->
+				<!-- wp:test/directives {
+					"data-wp-interactive": { "namespace": "test-1" },
+					"data-wp-context": { "text": "context-1" }
+				} -->
+					<!-- wp:test/directives {
+						"data-wp-interactive": { "namespace": "test-2" }
+					} /-->
+					<!-- wp:test/directives {
+						"class": "target",
+						"data-wp-bind--data-from-state": "state.text",
+						"data-wp-bind--data-from-context": "context.text"
+					} /-->
+				<!-- /wp:test/directives -->
+			<!-- /wp:test/directives -->
+		';
+
+		$html = do_blocks( $post_content );
+		$tags = new WP_HTML_Tag_Processor( $html );
+
+		$tags->next_tag( array( 'class_name' => 'target' ) );
+		$this->assertSame( 'state-1', $tags->get_attribute( 'data-from-state' ) );
+		$this->assertSame( 'context-1', $tags->get_attribute( 'data-from-context' ) );
+	}
+
+	public function test_namespace_can_be_overwritten_in_directives() {
+		/*
+		 * This function call should be done inside block render functions. We
+		 * run it here instead just for conveninence.
+		 */
+		wp_initial_state( 'test-1', array( 'text' => 'state-1' ) );
+		wp_initial_state( 'test-2', array( 'text' => 'state-2' ) );
+
+		$post_content = '
+			<!-- wp:test/directives { "data-wp-interactive": { "namespace": "test-1" } } -->
+					<!-- wp:test/directives {
+						"class": "inherited-ns",
+						"data-wp-bind--data-value": "state.text"
+					} /-->
+					<!-- wp:test/directives {
+						"class": "custom-ns",
+						"data-wp-bind--data-value": "test-2::state.text"
+					} /-->
+					<!-- wp:test/directives {
+						"class": "mixed-ns",
+						"data-wp-bind--data-inherited-ns": "state.text",
+						"data-wp-bind--data-custom-ns": "test-2::state.text"
+					} /-->
+			<!-- /wp:test/directives -->
+		';
+
+		$html = do_blocks( $post_content );
+		$tags = new WP_HTML_Tag_Processor( $html );
+
+		$tags->next_tag( array( 'class_name' => 'inherited-ns' ) );
+		$this->assertSame( 'state-1', $tags->get_attribute( 'data-value' ) );
+
+		$tags->next_tag( array( 'class_name' => 'custom-ns' ) );
+		$this->assertSame( 'state-2', $tags->get_attribute( 'data-value' ) );
+
+		$tags->next_tag( array( 'class_name' => 'mixed-ns' ) );
+		$this->assertSame( 'state-1', $tags->get_attribute( 'data-inherited-ns' ) );
+		$this->assertSame( 'state-2', $tags->get_attribute( 'data-custom-ns' ) );
+	}
 }

From b4490496bde5c7bbaf921cce01461ef381b98776 Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Tue, 9 Jan 2024 16:02:08 +0100
Subject: [PATCH 16/20] Fix typo in comments

---
 .../interactivity-api/directives/wp-interactive.php           | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/experimental/interactivity-api/directives/wp-interactive.php b/lib/experimental/interactivity-api/directives/wp-interactive.php
index 72a0f70274562..02800982bd726 100644
--- a/lib/experimental/interactivity-api/directives/wp-interactive.php
+++ b/lib/experimental/interactivity-api/directives/wp-interactive.php
@@ -33,8 +33,8 @@ function gutenberg_interactivity_process_wp_interactive( $tags, $context, $ns, &
 	 * definition was invalid or does not contain a namespace.
 	 *
 	 * This is done because the function pops out the current namespace from the
-	 * stack whenever it finds an island's closing tag, independtly of whether
-	 * the island definition was correct or contained a valid namespace.
+	 * stack whenever it finds an island's closing tag, independently of whether
+	 * the island definition was correct or it contained a valid namespace.
 	 */
 	$ns_stack[] = isset( $island_data ) && $island_data['namespace']
 		? $island_data['namespace']

From dcfc2c094f6d7fdd5e16f9cf0009f07c46a146dd Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Tue, 9 Jan 2024 16:05:00 +0100
Subject: [PATCH 17/20] Handle empty attributes in wp-interactive

---
 .../interactivity-api/directives/wp-interactive.php         | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/experimental/interactivity-api/directives/wp-interactive.php b/lib/experimental/interactivity-api/directives/wp-interactive.php
index 02800982bd726..9f3471a8b4e6a 100644
--- a/lib/experimental/interactivity-api/directives/wp-interactive.php
+++ b/lib/experimental/interactivity-api/directives/wp-interactive.php
@@ -23,10 +23,12 @@ function gutenberg_interactivity_process_wp_interactive( $tags, $context, $ns, &
 
 	/*
 	 * Decode the data-wp-interactive attribute. In the case it is not a valid
-	 * JSON string, the NULL value is stored in `$island_data`.
+	 * JSON string, NULL is stored in `$island_data`.
 	 */
 	$island      = $tags->get_attribute( 'data-wp-interactive' );
-	$island_data = json_decode( $island, true );
+	$island_data = is_string( $island ) && ! empty( $island )
+		? json_decode( $island, true )
+		: null;
 
 	/*
 	 * Push the newly defined namespace, or the current one if the island

From 4096915fb8c7cbbcadd88933dd9d31da0a534f07 Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Tue, 9 Jan 2024 16:08:17 +0100
Subject: [PATCH 18/20] Handle boolean attributes in wp-context

---
 lib/experimental/interactivity-api/directives/wp-context.php | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/experimental/interactivity-api/directives/wp-context.php b/lib/experimental/interactivity-api/directives/wp-context.php
index 43bfcfa926d2f..b41b47c86c78c 100644
--- a/lib/experimental/interactivity-api/directives/wp-context.php
+++ b/lib/experimental/interactivity-api/directives/wp-context.php
@@ -21,7 +21,9 @@ function gutenberg_interactivity_process_wp_context( $tags, $context, $ns ) {
 	$attr_value = $tags->get_attribute( 'data-wp-context' );
 
 	//Separate namespace and value from the context directive attribute.
-	list( $ns, $data ) = WP_Directive_Processor::parse_attribute_value( $attr_value, $ns );
+	list( $ns, $data ) = is_string( $attr_value ) && ! empty( $attr_value )
+		? WP_Directive_Processor::parse_attribute_value( $attr_value, $ns )
+		: array( $ns, null );
 
 	// Add parsed data to the context under the corresponding namespace.
 	$context->set_context( array( $ns => is_array( $data ) ? $data : array() ) );

From d8e650d724f55eb970ecc4afe057ddd1ab55b258 Mon Sep 17 00:00:00 2001
From: David Arenas <david.arenas@automattic.com>
Date: Tue, 9 Jan 2024 16:24:08 +0100
Subject: [PATCH 19/20] Do not support derived state yet

---
 .../interactivity-api/directive-processing.php           | 9 ++++++---
 .../interactivity-api/directive-processing-test.php      | 2 ++
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/lib/experimental/interactivity-api/directive-processing.php b/lib/experimental/interactivity-api/directive-processing.php
index 80d5ee71815da..b49ee538390ff 100644
--- a/lib/experimental/interactivity-api/directive-processing.php
+++ b/lib/experimental/interactivity-api/directive-processing.php
@@ -350,9 +350,12 @@ function gutenberg_interactivity_evaluate_reference( $reference, $ns, array $con
 	 * E.g., "file" is an string and a "callable" (the "file" function exists).
 	 */
 	if ( $current instanceof Closure ) {
-		// TODO: Do not pass the store as argument. Implement something similar
-		// to what we have in the JS runtime (`getContext()`, etc.).
-		$current = call_user_func( $current, $store );
+		/*
+		 * TODO: Figure out a way to implement derived state without having to
+		 * pass the store as argument:
+		 *
+		 * $current = call_user_func( $current );
+		 */
 	}
 
 	// Returns the opposite if it has a negator operator (!).
diff --git a/phpunit/experimental/interactivity-api/directive-processing-test.php b/phpunit/experimental/interactivity-api/directive-processing-test.php
index 4b7ca71a64c90..d6b5bc3860a95 100644
--- a/phpunit/experimental/interactivity-api/directive-processing-test.php
+++ b/phpunit/experimental/interactivity-api/directive-processing-test.php
@@ -310,6 +310,8 @@ public function test_evaluate_function_should_return_null_for_unresolved_paths()
 	}
 
 	public function test_evaluate_function_should_execute_anonymous_functions() {
+		$this->markTestSkipped( 'Derived state was supported for `wp_store()` but not for `wp_initial_state()` yet.' );
+
 		$context = new WP_Directive_Context( array( 'myblock' => array( 'count' => 2 ) ) );
 
 		wp_initial_state(

From 3e61b1e224a2622aa4017a31e8fa6f99d448e868 Mon Sep 17 00:00:00 2001
From: Carlos Bravo <carlos.bravo@automattic.com>
Date: Tue, 9 Jan 2024 18:35:46 +0100
Subject: [PATCH 20/20] Add root blocks bail out quick by name

---
 .../class-wp-directive-processor.php               | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/lib/experimental/interactivity-api/class-wp-directive-processor.php b/lib/experimental/interactivity-api/class-wp-directive-processor.php
index 0b5d63e2a25aa..3b8a38f973815 100644
--- a/lib/experimental/interactivity-api/class-wp-directive-processor.php
+++ b/lib/experimental/interactivity-api/class-wp-directive-processor.php
@@ -35,7 +35,11 @@ class WP_Directive_Processor extends Gutenberg_HTML_Tag_Processor_6_5 {
 	 * @param array $block The block to add.
 	 */
 	public static function mark_root_block( $block ) {
-		self::$root_block = md5( serialize( $block ) );
+		if ( null !== $block['blockName'] ) {
+			self::$root_block = $block['blockName'] . md5( serialize( $block ) );
+		} else {
+			self::$root_block = md5( serialize( $block ) );
+		}
 	}
 
 	/**
@@ -52,6 +56,14 @@ public static function unmark_root_block() {
 	 * @return bool True if block is a root block, false otherwise.
 	 */
 	public static function is_marked_as_root_block( $block ) {
+		// If self::$root_block is null, is impossible that any block has been marked as root.
+		if ( is_null( self::$root_block ) ) {
+			return false;
+		}
+		// Blocks whose blockName is null are specifically intended to convey - "this is a freeform HTML block."
+		if ( null !== $block['blockName'] ) {
+			return str_contains( self::$root_block, $block['blockName'] ) && $block['blockName'] . md5( serialize( $block ) ) === self::$root_block;
+		}
 		return md5( serialize( $block ) ) === self::$root_block;
 	}