Code Modernization: Use null coalescing operator instead of isset() ternaries in remaining core files.

Developed as a subset of #10654
Initially developed in #4886

Follow-up to [61456], [61455], [61454], [61453], [61445], [61444], [61443], [61442], [61436], [61435], [61434], [61403], [61433], [61432], [61431], [61430], [61429], [61424], [61404], [61403].

Props costdev, westonruter, jrf, SergeyBiryukov, swissspidy, hellofromTonya, marybaum, oglekler, dmsnell, chaion07, noisysocks, mukesh27.
See #63430.
Fixes #58874.


git-svn-id: https://develop.svn.wordpress.org/trunk@61457 602fd350-edb4-49c9-b593-d223f7449a82

Author: westonruter

src/wp-includes/IXR/class-IXR-client.php

@@ -31,8 +31,8 @@ function __construct( $server, $path = false, $port = 80, $timeout = 15 )
             // Assume we have been given a URL instead
             $bits = parse_url($server);
             $this->server = $bits['host'];
-            $this->port = isset($bits['port']) ? $bits['port'] : 80;
-            $this->path = isset($bits['path']) ? $bits['path'] : '/';
+            $this->port = $bits['port'] ?? 80;
+            $this->path = $bits['path'] ?? '/';
 
             // Make absolutely sure we have a path
             if (!$this->path) {

src/wp-includes/class-wp-duotone.php

@@ -209,7 +209,7 @@ private static function colord_parse_hue( $value, $unit = 'deg' ) {
 			'rad'  => 360 / ( M_PI * 2 ),
 		);
 
-		$factor = isset( $angle_units[ $unit ] ) ? $angle_units[ $unit ] : 1;
+		$factor = $angle_units[ $unit ] ?? 1;
 
 		return (float) $value * $factor;
 	}
@@ -972,9 +972,7 @@ private static function get_selector( $block_type ) {
 		 * If the experimental duotone support was set, that value is to be
 		 * treated as a selector and requires scoping.
 		 */
-		$experimental_duotone = isset( $block_type->supports['color']['__experimentalDuotone'] )
-			? $block_type->supports['color']['__experimentalDuotone']
-			: false;
+		$experimental_duotone = $block_type->supports['color']['__experimentalDuotone'] ?? false;
 		if ( $experimental_duotone ) {
 			$root_selector = wp_get_block_css_selector( $block_type );
 			return is_string( $experimental_duotone )
@@ -1003,7 +1001,7 @@ private static function get_all_global_styles_presets() {
 		}
 		// Get the per block settings from the theme.json.
 		$tree              = wp_get_global_settings();
-		$presets_by_origin = isset( $tree['color']['duotone'] ) ? $tree['color']['duotone'] : array();
+		$presets_by_origin = $tree['color']['duotone'] ?? array();
 
 		self::$global_styles_presets = array();
 		foreach ( $presets_by_origin as $presets ) {
@@ -1304,9 +1302,7 @@ public static function add_editor_settings( $settings ) {
 	 * @return array Filtered block type settings.
 	 */
 	public static function migrate_experimental_duotone_support_flag( $settings, $metadata ) {
-		$duotone_support = isset( $metadata['supports']['color']['__experimentalDuotone'] )
-			? $metadata['supports']['color']['__experimentalDuotone']
-			: null;
+		$duotone_support = $metadata['supports']['color']['__experimentalDuotone'] ?? null;
 
 		if ( ! isset( $settings['supports']['filter']['duotone'] ) && null !== $duotone_support ) {
 			_wp_array_set( $settings, array( 'supports', 'filter', 'duotone' ), (bool) $duotone_support );

src/wp-includes/class-wp-hook.php

@@ -492,7 +492,7 @@ public function offsetExists( $offset ) {
 	 */
 	#[ReturnTypeWillChange]
 	public function offsetGet( $offset ) {
-		return isset( $this->callbacks[ $offset ] ) ? $this->callbacks[ $offset ] : null;
+		return $this->callbacks[ $offset ] ?? null;
 	}
 
 	/**

src/wp-includes/class-wp-theme.php

@@ -515,7 +515,7 @@ public function __construct( $theme_dir, $theme_root, $_child = null ) {
 				return;
 			}
 			// Set the parent. Pass the current instance so we can do the checks above and assess errors.
-			$this->parent = new WP_Theme( $this->template, isset( $theme_root_template ) ? $theme_root_template : $this->theme_root, $this );
+			$this->parent = new WP_Theme( $this->template, $theme_root_template ?? $this->theme_root, $this );
 		}
 
 		if ( wp_paused_themes()->get( $this->stylesheet ) && ( ! is_wp_error( $this->errors ) || ! isset( $this->errors->errors['theme_paused'] ) ) ) {
@@ -776,7 +776,7 @@ public function exists() {
 	 * @return WP_Theme|false Parent theme, or false if the active theme is not a child theme.
 	 */
 	public function parent() {
-		return isset( $this->parent ) ? $this->parent : false;
+		return $this->parent ?? false;
 	}
 
 	/**
@@ -1397,7 +1397,7 @@ public function get_page_templates( $post = null, $post_type = 'page' ) {
 		}
 
 		$post_templates = $this->get_post_templates();
-		$post_templates = isset( $post_templates[ $post_type ] ) ? $post_templates[ $post_type ] : array();
+		$post_templates = $post_templates[ $post_type ] ?? array();
 
 		/**
 		 * Filters list of page templates for a theme.

src/wp-includes/deprecated.php

@@ -4264,9 +4264,7 @@ function wp_render_duotone_filter_preset( $preset ) {
 function wp_skip_border_serialization( $block_type ) {
 	_deprecated_function( __FUNCTION__, '6.0.0', 'wp_should_skip_block_supports_serialization()' );
 
-	$border_support = isset( $block_type->supports['__experimentalBorder'] )
-		? $block_type->supports['__experimentalBorder']
-		: false;
+	$border_support = $block_type->supports['__experimentalBorder'] ?? false;
 
 	return is_array( $border_support ) &&
 		array_key_exists( '__experimentalSkipSerialization', $border_support ) &&
@@ -4288,9 +4286,7 @@ function wp_skip_border_serialization( $block_type ) {
 function wp_skip_dimensions_serialization( $block_type ) {
 	_deprecated_function( __FUNCTION__, '6.0.0', 'wp_should_skip_block_supports_serialization()' );
 
-	$dimensions_support = isset( $block_type->supports['__experimentalDimensions'] )
-		? $block_type->supports['__experimentalDimensions']
-		: false;
+	$dimensions_support = $block_type->supports['__experimentalDimensions'] ?? false;
 
 	return is_array( $dimensions_support ) &&
 		array_key_exists( '__experimentalSkipSerialization', $dimensions_support ) &&
@@ -4312,9 +4308,7 @@ function wp_skip_dimensions_serialization( $block_type ) {
 function wp_skip_spacing_serialization( $block_type ) {
 	_deprecated_function( __FUNCTION__, '6.0.0', 'wp_should_skip_block_supports_serialization()' );
 
-	$spacing_support = isset( $block_type->supports['spacing'] )
-		? $block_type->supports['spacing']
-		: false;
+	$spacing_support = $block_type->supports['spacing'] ?? false;
 
 	return is_array( $spacing_support ) &&
 		array_key_exists( '__experimentalSkipSerialization', $spacing_support ) &&

src/wp-includes/pluggable.php

@@ -1722,7 +1722,7 @@ function wp_validate_redirect( $location, $fallback_url = '' ) {
 		 * @param string[] $hosts An array of allowed host names.
 		 * @param string   $host  The host name of the redirect destination; empty string if not set.
 		 */
-		$allowed_hosts = (array) apply_filters( 'allowed_redirect_hosts', array( $wpp['host'] ), isset( $lp['host'] ) ? $lp['host'] : '' );
+		$allowed_hosts = (array) apply_filters( 'allowed_redirect_hosts', array( $wpp['host'] ), $lp['host'] ?? '' );
 
 		if ( isset( $lp['host'] ) && ( ! in_array( $lp['host'], $allowed_hosts, true ) && strtolower( $wpp['host'] ) !== $lp['host'] ) ) {
 			$location = $fallback_url;

src/wp-includes/theme.php

@@ -1104,7 +1104,7 @@ function get_theme_mod( $name, $default_value = false ) {
  */
 function set_theme_mod( $name, $value ) {
 	$mods      = get_theme_mods();
-	$old_value = isset( $mods[ $name ] ) ? $mods[ $name ] : false;
+	$old_value = $mods[ $name ] ?? false;
 
 	/**
 	 * Filters the theme modification, or 'theme_mod', value on save.
@@ -3428,7 +3428,7 @@ function get_registered_theme_feature( $feature ) {
 		return null;
 	}
 
-	return isset( $_wp_registered_theme_features[ $feature ] ) ? $_wp_registered_theme_features[ $feature ] : null;
+	return $_wp_registered_theme_features[ $feature ] ?? null;
 }
 
 /**