Upgrade/Install: Reduce number of DB queries populating roles.

Reduces the number of database queries made when populating roles during install/multisite site creation by 344 (347 queries down to 3).

`populate_roles()` has been modified to prevent an individual database query each time a role or capability is added to the `WP_Roles` object. Instead the roles option, `{$wpdb->prefix}user_roles` is updated once at the end of the function call.

Introduces a test to ensure that updating the roles option via `WP_Roles` and updating the option in the manner now used by `populate_roles()` results in the same capabilities been applied to a role.

Props fliespl, johnjamesjacoby, ocean90, realloc, rishabhwp, sainathpoojary, sirlouen, spacedmonkey, swissspidy.
Fixes #37687.



git-svn-id: https://develop.svn.wordpress.org/trunk@60614 602fd350-edb4-49c9-b593-d223f7449a82

Author: peterwilsoncc

src/wp-admin/includes/schema.php

@@ -713,6 +713,13 @@ function populate_options( array $options = array() ) {
  * @since 2.0.0
  */
 function populate_roles() {
+	$wp_roles = wp_roles();
+
+	// Disable role updates to the database while populating roles.
+	$original_use_db  = $wp_roles->use_db;
+	$wp_roles->use_db = false;
+
+	// Populate roles
 	populate_roles_160();
 	populate_roles_210();
 	populate_roles_230();
@@ -721,6 +728,14 @@ function populate_roles() {
 	populate_roles_270();
 	populate_roles_280();
 	populate_roles_300();
+
+	// Save the updated roles to the database.
+	if ( $original_use_db ) {
+		update_option( $wp_roles->role_key, $wp_roles->roles, true );
+	}
+
+	// Restore original value for writing to database.
+	$wp_roles->use_db = $original_use_db;
 }
 
 /**

tests/phpunit/tests/user/capabilities.php

@@ -2542,4 +2542,55 @@ public function test_edit_block_binding_caps_are_mapped_correctly() {
 			);
 		}
 	}
+
+	/**
+	 * Ensure that caps are updated correctly when using `update_option()` to save roles.
+	 *
+	 * Compares the efficiency and accuracy of updating role capabilities when `WP_Roles`
+	 * uses the database vs when the updates are done via `update_option()`.
+	 *
+	 * This method of updating roles is used in `populate_roles()` to reduce the number of
+	 * queries by approximately 300.
+	 *
+	 * @ticket 37687
+	 */
+	public function test_role_capabilities_updated_correctly_via_update_option() {
+		global $wp_roles;
+		$emcee_role = 'emcee';
+		$wp_roles->add_role( $emcee_role, 'Emcee', array( 'level_1' => true ) );
+		$this->flush_roles();
+
+		$expected_caps = array(
+			'level_1'             => true,
+			'attend_kit_kat_klub' => true,
+			'win_tony_award'      => true,
+		);
+
+		$start_queries = get_num_queries();
+		$wp_roles->add_cap( $emcee_role, 'attend_kit_kat_klub' );
+		$wp_roles->add_cap( $emcee_role, 'win_tony_award' );
+		$emcee_queries = get_num_queries() - $start_queries;
+		$this->flush_roles();
+		$emcee_caps = $wp_roles->get_role( $emcee_role )->capabilities;
+
+		$wp_roles->use_db = false;
+		$sally_role       = 'sally';
+		$wp_roles->add_role( $sally_role, 'Sally Bowles', array( 'level_1' => true ) );
+		$start_queries = get_num_queries();
+		$wp_roles->add_cap( $sally_role, 'attend_kit_kat_klub' );
+		$wp_roles->add_cap( $sally_role, 'win_tony_award' );
+
+		update_option( $wp_roles->role_key, $wp_roles->roles, true );
+		$sally_queries    = get_num_queries() - $start_queries;
+		$wp_roles->use_db = true;
+
+		// Restore the default value.
+		$this->flush_roles();
+		$sally_caps = $wp_roles->get_role( $sally_role )->capabilities;
+
+		$this->assertSameSetsWithIndex( $expected_caps, $emcee_caps, 'Emcee role should include the three expected capabilities.' );
+		$this->assertSameSetsWithIndex( $expected_caps, $sally_caps, 'Sally role should include the three expected capabilities.' );
+		$this->assertSameSetsWithIndex( $emcee_caps, $sally_caps, 'Emcee and Sally roles should have the same capabilities after update.' );
+		$this->assertLessThan( $emcee_queries, $sally_queries, 'Updating roles via update_option should be more efficient than WP_Roles using the database.' );
+	}
 }