Fonts: Get font-family name from 'fontFamily' field.

Instead of getting the name from the optional `'name'` field, the font-family name now comes from the required `'fontFamily'` field.

This change fixes a back-compat (BC) break in how the font-family name is pulled from the incoming font data in the `WP_Font_Face_Resolver`.

Why?

WP Core does not require the `'name'` field in theme.json. For themes that do not declare it, that set of font variations is ignored, thus causing a BC break from how the stopgap code worked (see [53282]).

However, `WP_Theme_JSON` schema does require the `fontFamily` field in each of the `typography.fontFamilies`.

== Other details:

Includes a parser to extract the first entry when a `fontFamily` field has a comma-separated list of font-families, e.g. `Inter, sans-serif`.

References:
* Merge from Gutenberg's PR WordPress/gutenberg#54615.

Follow-up to [56500], [53282].

Props ironprogrammer, hellofromTonya, mmaattiiaass, pbking.
Fixes #59165.
Built from https://develop.svn.wordpress.org/trunk@56688


git-svn-id: http://core.svn.wordpress.org/trunk@56200 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/fonts/class-wp-font-face-resolver.php

@@ -50,30 +50,54 @@ private static function parse_settings( array $settings ) {
 		foreach ( $settings['typography']['fontFamilies'] as $font_families ) {
 			foreach ( $font_families as $definition ) {
 
-				// Skip if font-family "name" is not defined.
-				if ( empty( $definition['name'] ) ) {
+				// Skip if "fontFace" is not defined, meaning there are no variations.
+				if ( empty( $definition['fontFace'] ) ) {
 					continue;
 				}
 
-				// Skip if "fontFace" is not defined, meaning there are no variations.
-				if ( empty( $definition['fontFace'] ) ) {
+				// Skip if "fontFamily" is not defined.
+				if ( empty( $definition['fontFamily'] ) ) {
 					continue;
 				}
 
-				$font_family = $definition['name'];
+				$font_family_name = static::maybe_parse_name_from_comma_separated_list( $definition['fontFamily'] );
+
+				// Skip if no font family is defined.
+				if ( empty( $font_family_name ) ) {
+					continue;
+				}
 
 				// Prepare the fonts array structure for this font-family.
-				if ( ! array_key_exists( $font_family, $fonts ) ) {
-					$fonts[ $font_family ] = array();
+				if ( ! array_key_exists( $font_family_name, $fonts ) ) {
+					$fonts[ $font_family_name ] = array();
 				}
 
-				$fonts[ $font_family ] = static::convert_font_face_properties( $definition['fontFace'], $font_family );
+				$fonts[ $font_family_name ] = static::convert_font_face_properties( $definition['fontFace'], $font_family_name );
 			}
 		}
 
 		return $fonts;
 	}
 
+	/**
+	 * Parse font-family name from comma-separated lists.
+	 *
+	 * If the given `fontFamily` is a comma-separated lists (example: "Inter, sans-serif" ),
+	 * parse and return the fist font from the list.
+	 *
+	 * @since 6.4.0
+	 *
+	 * @param string $font_family Font family `fontFamily' to parse.
+	 * @return string Font-family name.
+	 */
+	private static function maybe_parse_name_from_comma_separated_list( $font_family ) {
+		if ( str_contains( $font_family, ',' ) ) {
+			$font_family = explode( ',', $font_family )[0];
+		}
+
+		return trim( $font_family, "\"'" );
+	}
+
 	/**
 	 * Converts font-face properties from theme.json format.
 	 *

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.4-alpha-56687';
+$wp_version = '6.4-alpha-56688';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.