Icons: Enforce strict name validation in the register method.

Reject icon names that use uppercase letters, that lack a namespace prefix, or that have already been registered. Add tests covering these cases.

Props im3dabasia1, mukesh27, wildworks.
See #64847.

Built from https://develop.svn.wordpress.org/trunk@62515


git-svn-id: http://core.svn.wordpress.org/trunk@61796 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/class-wp-icons-registry.php

@@ -115,6 +115,34 @@ class WP_Icons_Registry {
 			return false;
 		}
 
+		if ( preg_match( '/[A-Z]/', $icon_name ) ) {
+			_doing_it_wrong(
+				__METHOD__,
+				__( 'Icon names must not contain uppercase characters.' ),
+				'7.1.0'
+			);
+			return false;
+		}
+
+		$name_matcher = '/^[a-z][a-z0-9-]*\/[a-z][a-z0-9-]*$/';
+		if ( ! preg_match( $name_matcher, $icon_name ) ) {
+			_doing_it_wrong(
+				__METHOD__,
+				__( 'Icon names must contain a namespace prefix. Example: my-plugin/my-custom-icon' ),
+				'7.1.0'
+			);
+			return false;
+		}
+
+		if ( $this->is_registered( $icon_name ) ) {
+			_doing_it_wrong(
+				__METHOD__,
+				__( 'Icon is already registered.' ),
+				'7.1.0'
+			);
+			return false;
+		}
+
 		$allowed_keys = array_fill_keys( array( 'label', 'content', 'filePath' ), 1 );
 		foreach ( array_keys( $icon_properties ) as $key ) {
 			if ( ! array_key_exists( $key, $allowed_keys ) ) {

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '7.1-alpha-62514';
+$wp_version = '7.1-alpha-62515';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.