Coding Standards: Fix instances of WordPress.PHP.NoSilencedErrors.Discouraged.

Noteable changes:
- The `magic_quotes_runtime` and `magic_quotes_sybase` settings were removed in PHP 5.4, so no longer need to be set.
- Some functions that use external libraries can generate errors that can't be tested for, so are globally allowed to silence errors.
- Quite a few functions would cause errors if `safe_mode` was set. This setting was removed in PHP 5.4.
- Only a handful of `header()` calls needed corresponding `headers_sent()` checks for unit tests to pass, but more may need to be added as the nightlies builds are tested.

See #46732.


git-svn-id: https://develop.svn.wordpress.org/trunk@45611 602fd350-edb4-49c9-b593-d223f7449a82

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

@@ -89,7 +89,7 @@ class _WP_Dependency {
 	 * @since 2.6.0
 	 */
 	public function __construct() {
-		@list( $this->handle, $this->src, $this->deps, $this->ver, $this->args ) = func_get_args();
+		list( $this->handle, $this->src, $this->deps, $this->ver, $this->args ) = func_get_args();
 		if ( ! is_array( $this->deps ) ) {
 			$this->deps = array();
 		}

src/wp-includes/class-wp-http-streams.php

@@ -140,8 +140,10 @@ class WP_Http_Streams {
 			}
 
 			if ( $proxy->is_enabled() && $proxy->send_through_proxy( $url ) ) {
+				// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged
 				$handle = @stream_socket_client( 'tcp://' . $proxy->host() . ':' . $proxy->port(), $connection_error, $connection_error_str, $connect_timeout, STREAM_CLIENT_CONNECT, $context );
 			} else {
+				// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged
 				$handle = @stream_socket_client( $connect_host . ':' . $arrURL['port'], $connection_error, $connection_error_str, $connect_timeout, STREAM_CLIENT_CONNECT, $context );
 			}
 

src/wp-includes/class-wp-image-editor-gd.php

@@ -436,7 +436,7 @@ class WP_Image_Editor_GD extends WP_Image_Editor {
 		// Set correct file permissions
 		$stat  = stat( dirname( $filename ) );
 		$perms = $stat['mode'] & 0000666; //same permissions as parent folder, strip off the executable bits
-		@ chmod( $filename, $perms );
+		chmod( $filename, $perms );
 
 		/**
 		 * Filters the name of the saved image file.

src/wp-includes/class-wp-image-editor-imagick.php

@@ -113,6 +113,7 @@ class WP_Image_Editor_Imagick extends WP_Image_Editor {
 		}
 
 		try {
+			// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged
 			return ( (bool) @Imagick::queryFormats( $imagick_extension ) );
 		} catch ( Exception $e ) {
 			return false;
@@ -654,7 +655,7 @@ class WP_Image_Editor_Imagick extends WP_Image_Editor {
 		// Set correct file permissions
 		$stat  = stat( dirname( $filename ) );
 		$perms = $stat['mode'] & 0000666; //same permissions as parent folder, strip off the executable bits
-		@ chmod( $filename, $perms );
+		chmod( $filename, $perms );
 
 		/** This filter is documented in wp-includes/class-wp-image-editor-gd.php */
 		return array(

src/wp-includes/class-wp.php

@@ -492,23 +492,15 @@ class WP {
 		if ( isset( $headers['Last-Modified'] ) && false === $headers['Last-Modified'] ) {
 			unset( $headers['Last-Modified'] );
 
-			// In PHP 5.3+, make sure we are not sending a Last-Modified header.
-			if ( function_exists( 'header_remove' ) ) {
-				@header_remove( 'Last-Modified' );
-			} else {
-				// In PHP 5.2, send an empty Last-Modified header, but only as a
-				// last resort to override a header already sent. #WP23021
-				foreach ( headers_list() as $header ) {
-					if ( 0 === stripos( $header, 'Last-Modified' ) ) {
-						$headers['Last-Modified'] = '';
-						break;
-					}
-				}
+			if ( ! headers_sent() ) {
+				header_remove( 'Last-Modified' );
 			}
 		}
 
-		foreach ( (array) $headers as $name => $field_value ) {
-			@header( "{$name}: {$field_value}" );
+		if ( ! headers_sent() ) {
+			foreach ( (array) $headers as $name => $field_value ) {
+				header( "{$name}: {$field_value}" );
+			}
 		}
 
 		if ( $exit_required ) {
@@ -674,8 +666,8 @@ class WP {
 				}
 
 				// Only set X-Pingback for single posts that allow pings.
-				if ( $p && pings_open( $p ) ) {
-					@header( 'X-Pingback: ' . get_bloginfo( 'pingback_url', 'display' ) );
+				if ( $p && pings_open( $p ) && ! headers_sent() ) {
+					header( 'X-Pingback: ' . get_bloginfo( 'pingback_url', 'display' ) );
 				}
 
 				// check for paged content that exceeds the max number of pages

src/wp-includes/comment.php

@@ -2608,9 +2608,9 @@ function discover_pingback_server_uri( $url, $deprecated = '' ) {
 	if ( $pingback_link_offset_dquote || $pingback_link_offset_squote ) {
 		$quote                   = ( $pingback_link_offset_dquote ) ? '"' : '\'';
 		$pingback_link_offset    = ( $quote == '"' ) ? $pingback_link_offset_dquote : $pingback_link_offset_squote;
-		$pingback_href_pos       = @strpos( $contents, 'href=', $pingback_link_offset );
+		$pingback_href_pos       = strpos( $contents, 'href=', $pingback_link_offset );
 		$pingback_href_start     = $pingback_href_pos + 6;
-		$pingback_href_end       = @strpos( $contents, $quote, $pingback_href_start );
+		$pingback_href_end       = strpos( $contents, $quote, $pingback_href_start );
 		$pingback_server_url_len = $pingback_href_end - $pingback_href_start;
 		$pingback_server_url     = substr( $contents, $pingback_href_start, $pingback_server_url_len );
 
@@ -2808,7 +2808,7 @@ function pingback( $content, $post_id ) {
 		$pingback_server_url = discover_pingback_server_uri( $pagelinkedto );
 
 		if ( $pingback_server_url ) {
-			@ set_time_limit( 60 );
+			set_time_limit( 60 );
 			// Now, the RPC call
 			$pagelinkedfrom = get_permalink( $post );
 

src/wp-includes/compat.php

@@ -35,6 +35,7 @@ function _wp_can_use_pcre_u( $set = null ) {
 	}
 
 	if ( 'reset' === $utf8_pcre ) {
+		// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged -- intentional error generated to detect PCRE/u support.
 		$utf8_pcre = @preg_match( '/^./u', 'a' );
 	}
 

src/wp-includes/cron.php

@@ -677,11 +677,10 @@ function spawn_cron( $gmt_time = 0 ) {
 		echo ' ';
 
 		// flush any buffers and send the headers
-		while ( @ob_end_flush() ) {
-		}
+		wp_ob_end_flush_all();
 		flush();
 
-		WP_DEBUG ? include_once( ABSPATH . 'wp-cron.php' ) : @include_once( ABSPATH . 'wp-cron.php' );
+		include_once( ABSPATH . 'wp-cron.php' );
 		return true;
 	}
 

src/wp-includes/default-constants.php

@@ -34,7 +34,7 @@ function wp_initial_constants() {
 		define( 'WP_START_TIMESTAMP', microtime( true ) );
 	}
 
-	$current_limit     = @ini_get( 'memory_limit' );
+	$current_limit     = ini_get( 'memory_limit' );
 	$current_limit_int = wp_convert_hr_to_bytes( $current_limit );
 
 	// Define memory limits.
@@ -61,7 +61,7 @@ function wp_initial_constants() {
 	// Set memory limits.
 	$wp_limit_int = wp_convert_hr_to_bytes( WP_MEMORY_LIMIT );
 	if ( -1 !== $current_limit_int && ( -1 === $wp_limit_int || $wp_limit_int > $current_limit_int ) ) {
-		@ini_set( 'memory_limit', WP_MEMORY_LIMIT );
+		ini_set( 'memory_limit', WP_MEMORY_LIMIT );
 	}
 
 	if ( ! isset( $blog_id ) ) {

src/wp-includes/deprecated.php

@@ -1923,7 +1923,7 @@ function get_attachment_icon( $id = 0, $fullsize = false, $max_dims = false ) {
 	// Do we need to constrain the image?
 	if ( ($max_dims = apply_filters('attachment_max_dims', $max_dims)) && file_exists($src_file) ) {
 
-		$imagesize = getimagesize($src_file);
+		$imagesize = @getimagesize($src_file);
 
 		if (($imagesize[0] > $max_dims[0]) || $imagesize[1] > $max_dims[1] ) {
 			$actual_aspect = $imagesize[0] / $imagesize[1];

src/wp-includes/feed.php

@@ -407,7 +407,7 @@ function get_the_category_rss( $type = null ) {
 		} elseif ( 'atom' == $type ) {
 			$the_list .= sprintf( '<category scheme="%1$s" term="%2$s" />', esc_attr( get_bloginfo_rss( 'url' ) ), esc_attr( $cat_name ) );
 		} else {
-			$the_list .= "\t\t<category><![CDATA[" . @html_entity_decode( $cat_name, ENT_COMPAT, get_option( 'blog_charset' ) ) . "]]></category>\n";
+			$the_list .= "\t\t<category><![CDATA[" . html_entity_decode( $cat_name, ENT_COMPAT, get_option( 'blog_charset' ) ) . "]]></category>\n";
 		}
 	}
 

src/wp-includes/formatting.php

@@ -994,7 +994,7 @@ function _wp_specialchars( $string, $quote_style = ENT_NOQUOTES, $charset = fals
 		$string = wp_kses_normalize_entities( $string );
 	}
 
-	$string = @htmlspecialchars( $string, $quote_style, $charset, $double_encode );
+	$string = htmlspecialchars( $string, $quote_style, $charset, $double_encode );
 
 	// Back-compat.
 	if ( 'single' === $_quote_style ) {
@@ -1129,6 +1129,7 @@ function wp_check_invalid_utf8( $string, $strip = false ) {
 	// Check for support for utf8 in the installed PCRE library once and store the result in a static
 	static $utf8_pcre = null;
 	if ( ! isset( $utf8_pcre ) ) {
+		// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged
 		$utf8_pcre = @preg_match( '/^./u', 'a' );
 	}
 	// We can't demand utf8 in the PCRE installation, so just return the string in those cases
@@ -1136,7 +1137,7 @@ function wp_check_invalid_utf8( $string, $strip = false ) {
 		return $string;
 	}
 
-	// preg_match fails when it encounters invalid UTF8 in $string
+	// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged -- preg_match fails when it encounters invalid UTF8 in $string
 	if ( 1 === @preg_match( '/^./us', $string ) ) {
 		return $string;
 	}

src/wp-includes/functions.php

@@ -97,7 +97,7 @@ function date_i18n( $dateformatstring, $timestamp_with_offset = false, $gmt = fa
 	global $wp_locale;
 	$i = $timestamp_with_offset;
 
-	if ( false === $i ) {
+	if ( ! is_numeric( $i ) ) {
 		$i = current_time( 'timestamp', $gmt );
 	}
 
@@ -177,7 +177,7 @@ function date_i18n( $dateformatstring, $timestamp_with_offset = false, $gmt = fa
 			}
 		}
 	}
-	$j = @gmdate( $dateformatstring, $i );
+	$j = gmdate( $dateformatstring, $i );
 
 	/**
 	 * Filters the date formatted based on the locale.
@@ -224,7 +224,7 @@ function wp_maybe_decline_date( $date ) {
 		$months_genitive = $wp_locale->month_genitive;
 
 		// Match a format like 'j F Y' or 'j. F'
-		if ( @preg_match( '#^\d{1,2}\.? [^\d ]+#u', $date ) ) {
+		if ( preg_match( '#^\d{1,2}\.? [^\d ]+#u', $date ) ) {
 
 			foreach ( $months as $key => $month ) {
 				$months[ $key ] = '# ' . $month . '( |$)#u';
@@ -238,7 +238,7 @@ function wp_maybe_decline_date( $date ) {
 		}
 
 		// Match a format like 'F jS' or 'F j' and change it to 'j F'
-		if ( @preg_match( '#^[^\d ]+ \d{1,2}(st|nd|rd|th)? #u', trim( $date ) ) ) {
+		if ( preg_match( '#^[^\d ]+ \d{1,2}(st|nd|rd|th)? #u', trim( $date ) ) ) {
 			foreach ( $months as $key => $month ) {
 				$months[ $key ] = '#' . $month . ' (\d{1,2})(st|nd|rd|th)?#u';
 			}
@@ -1258,7 +1258,9 @@ function status_header( $code, $description = '' ) {
 		$status_header = apply_filters( 'status_header', $status_header, $code, $description, $protocol );
 	}
 
-	@header( $status_header, true, $code );
+	if ( ! headers_sent() ) {
+		header( $status_header, true, $code );
+	}
 }
 
 /**
@@ -1310,26 +1312,18 @@ function wp_get_nocache_headers() {
  * @see wp_get_nocache_headers()
  */
 function nocache_headers() {
+	if ( headers_sent() ) {
+		return;
+	}
+
 	$headers = wp_get_nocache_headers();
 
 	unset( $headers['Last-Modified'] );
 
-	// In PHP 5.3+, make sure we are not sending a Last-Modified header.
-	if ( function_exists( 'header_remove' ) ) {
-		@header_remove( 'Last-Modified' );
-	} else {
-		// In PHP 5.2, send an empty Last-Modified header, but only as a
-		// last resort to override a header already sent. #WP23021
-		foreach ( headers_list() as $header ) {
-			if ( 0 === stripos( $header, 'Last-Modified' ) ) {
-				$headers['Last-Modified'] = '';
-				break;
-			}
-		}
-	}
+	header_remove( 'Last-Modified' );
 
 	foreach ( $headers as $name => $field_value ) {
-		@header( "{$name}: {$field_value}" );
+		header( "{$name}: {$field_value}" );
 	}
 }
 
@@ -1829,7 +1823,7 @@ function wp_mkdir_p( $target ) {
 		if ( $dir_perms != ( $dir_perms & ~umask() ) ) {
 			$folder_parts = explode( '/', substr( $target, strlen( $target_parent ) + 1 ) );
 			for ( $i = 1, $c = count( $folder_parts ); $i <= $c; $i++ ) {
-				@chmod( $target_parent . '/' . implode( '/', array_slice( $folder_parts, 0, $i ) ), $dir_perms );
+				chmod( $target_parent . '/' . implode( '/', array_slice( $folder_parts, 0, $i ) ), $dir_perms );
 			}
 		}
 
@@ -2421,12 +2415,12 @@ function wp_upload_bits( $name, $deprecated, $bits, $time = null ) {
 		return array( 'error' => $message );
 	}
 
-	$ifp = @ fopen( $new_file, 'wb' );
+	$ifp = @fopen( $new_file, 'wb' );
 	if ( ! $ifp ) {
 		return array( 'error' => sprintf( __( 'Could not write file %s' ), $new_file ) );
 	}
 
-	@fwrite( $ifp, $bits );
+	fwrite( $ifp, $bits );
 	fclose( $ifp );
 	clearstatcache();
 
@@ -2434,7 +2428,7 @@ function wp_upload_bits( $name, $deprecated, $bits, $time = null ) {
 	$stat  = @ stat( dirname( $new_file ) );
 	$perms = $stat['mode'] & 0007777;
 	$perms = $perms & 0000666;
-	@ chmod( $new_file, $perms );
+	chmod( $new_file, $perms );
 	clearstatcache();
 
 	// Compute the URL
@@ -2707,7 +2701,7 @@ function wp_get_image_mime( $file ) {
 			$imagetype = exif_imagetype( $file );
 			$mime      = ( $imagetype ) ? image_type_to_mime_type( $imagetype ) : false;
 		} elseif ( function_exists( 'getimagesize' ) ) {
-			$imagesize = getimagesize( $file );
+			$imagesize = @getimagesize( $file );
 			$mime      = ( isset( $imagesize['mime'] ) ) ? $imagesize['mime'] : false;
 		} else {
 			$mime = false;
@@ -3601,6 +3595,7 @@ function wp_json_encode( $data, $options = 0, $depth = 512 ) {
 	// Prepare the data for JSON serialization.
 	$args[0] = _wp_json_prepare_data( $data );
 
+	// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged -- json_encode() errors are handled after this call
 	$json = @call_user_func_array( 'json_encode', $args );
 
 	// If json_encode() was successful, no need to do more sanity checking.
@@ -3775,10 +3770,13 @@ function _wp_json_prepare_data( $data ) {
  * @param int   $status_code The HTTP status code to output.
  */
 function wp_send_json( $response, $status_code = null ) {
-	@header( 'Content-Type: application/json; charset=' . get_option( 'blog_charset' ) );
-	if ( null !== $status_code ) {
-		status_header( $status_code );
+	if ( ! headers_sent() ) {
+		header( 'Content-Type: application/json; charset=' . get_option( 'blog_charset' ) );
+		if ( null !== $status_code ) {
+			status_header( $status_code );
+		}
 	}
+
 	echo wp_json_encode( $response );
 
 	if ( wp_doing_ajax() ) {
@@ -5726,7 +5724,7 @@ function __return_empty_string() { // phpcs:ignore WordPress.NamingConventions.V
  * @see https://src.chromium.org/viewvc/chrome?view=rev&revision=6985
  */
 function send_nosniff_header() {
-	@header( 'X-Content-Type-Options: nosniff' );
+	header( 'X-Content-Type-Options: nosniff' );
 }
 
 /**
@@ -5840,7 +5838,7 @@ function wp_find_hierarchy_loop_tortoise_hare( $callback, $start, $override = ar
  * @see https://developer.mozilla.org/en/the_x-frame-options_response_header
  */
 function send_frame_options_header() {
-	@header( 'X-Frame-Options: SAMEORIGIN' );
+	header( 'X-Frame-Options: SAMEORIGIN' );
 }
 
 /**
@@ -6414,7 +6412,7 @@ function wp_raise_memory_limit( $context = 'admin' ) {
 		return false;
 	}
 
-	$current_limit     = @ini_get( 'memory_limit' );
+	$current_limit     = ini_get( 'memory_limit' );
 	$current_limit_int = wp_convert_hr_to_bytes( $current_limit );
 
 	if ( -1 === $current_limit_int ) {
@@ -6486,13 +6484,13 @@ function wp_raise_memory_limit( $context = 'admin' ) {
 	$filtered_limit_int = wp_convert_hr_to_bytes( $filtered_limit );
 
 	if ( -1 === $filtered_limit_int || ( $filtered_limit_int > $wp_max_limit_int && $filtered_limit_int > $current_limit_int ) ) {
-		if ( false !== @ini_set( 'memory_limit', $filtered_limit ) ) {
+		if ( false !== ini_set( 'memory_limit', $filtered_limit ) ) {
 			return $filtered_limit;
 		} else {
 			return false;
 		}
 	} elseif ( -1 === $wp_max_limit_int || $wp_max_limit_int > $current_limit_int ) {
-		if ( false !== @ini_set( 'memory_limit', $wp_max_limit ) ) {
+		if ( false !== ini_set( 'memory_limit', $wp_max_limit ) ) {
 			return $wp_max_limit;
 		} else {
 			return false;
@@ -7179,13 +7177,13 @@ function recurse_dirsize( $directory, $exclude = null, $max_execution_time = nul
 }
 
 /**
-* Checks compatibility with the current WordPress version.
-*
-* @since 5.2.0
-*
-* @param string $required Minimum required WordPress version.
-* @return bool True if required version is compatible or empty, false if not.
-*/
+ * Checks compatibility with the current WordPress version.
+ *
+ * @since 5.2.0
+ *
+ * @param string $required Minimum required WordPress version.
+ * @return bool True if required version is compatible or empty, false if not.
+ */
 function is_wp_version_compatible( $required ) {
 	return empty( $required ) || version_compare( get_bloginfo( 'version' ), $required, '>=' );
 }

src/wp-includes/http.php

@@ -496,8 +496,8 @@ function send_origin_headers() {
 	$origin = get_http_origin();
 
 	if ( is_allowed_http_origin( $origin ) ) {
-		@header( 'Access-Control-Allow-Origin: ' . $origin );
-		@header( 'Access-Control-Allow-Credentials: true' );
+		header( 'Access-Control-Allow-Origin: ' . $origin );
+		header( 'Access-Control-Allow-Credentials: true' );
 		if ( 'OPTIONS' === $_SERVER['REQUEST_METHOD'] ) {
 			exit;
 		}

src/wp-includes/load.php

@@ -352,7 +352,7 @@ function wp_debug_mode() {
 	}
 
 	if ( defined( 'XMLRPC_REQUEST' ) || defined( 'REST_REQUEST' ) || ( defined( 'WP_INSTALLING' ) && WP_INSTALLING ) || wp_doing_ajax() || wp_is_json_request() ) {
-		@ini_set( 'display_errors', 0 );
+		ini_set( 'display_errors', 0 );
 	}
 }
 
@@ -908,6 +908,7 @@ function is_protected_ajax_action() {
 function wp_set_internal_encoding() {
 	if ( function_exists( 'mb_internal_encoding' ) ) {
 		$charset = get_option( 'blog_charset' );
+		// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged
 		if ( ! $charset || ! @mb_internal_encoding( $charset ) ) {
 			mb_internal_encoding( 'UTF-8' );
 		}

src/wp-includes/media.php

@@ -238,7 +238,7 @@ function image_downsize( $id, $size = 'medium' ) {
 		$info       = null;
 
 		if ( $thumb_file ) {
-			$info = getimagesize( $thumb_file );
+			$info = @getimagesize( $thumb_file );
 		}
 
 		if ( $thumb_file && $info ) {
@@ -910,8 +910,8 @@ function wp_get_attachment_image_src( $attachment_id, $size = 'thumbnail', $icon
 				/** This filter is documented in wp-includes/post.php */
 				$icon_dir = apply_filters( 'icon_dir', ABSPATH . WPINC . '/images/media' );
 
-				$src_file                = $icon_dir . '/' . wp_basename( $src );
-				@list( $width, $height ) = getimagesize( $src_file );
+				$src_file               = $icon_dir . '/' . wp_basename( $src );
+				list( $width, $height ) = @getimagesize( $src_file );
 			}
 		}
 

src/wp-includes/pluggable.php

@@ -1522,7 +1522,10 @@ if ( ! function_exists( 'wp_notify_postauthor' ) ) :
 
 		$switched_locale = switch_to_locale( get_locale() );
 
-		$comment_author_domain = @gethostbyaddr( $comment->comment_author_IP );
+		$comment_author_domain = '';
+		if ( WP_Http::is_ip_address( $comment->comment_author_IP ) ) {
+			$comment_author_domain = gethostbyaddr( $comment->comment_author_IP );
+		}
 
 		// The blogname option is escaped with esc_html on the way into the database in sanitize_option
 		// we want to reverse this for the plain text arena of emails.
@@ -1639,7 +1642,7 @@ if ( ! function_exists( 'wp_notify_postauthor' ) ) :
 		$message_headers = apply_filters( 'comment_notification_headers', $message_headers, $comment->comment_ID );
 
 		foreach ( $emails as $email ) {
-			@wp_mail( $email, wp_specialchars_decode( $subject ), $notify_message, $message_headers );
+			wp_mail( $email, wp_specialchars_decode( $subject ), $notify_message, $message_headers );
 		}
 
 		if ( $switched_locale ) {
@@ -1696,8 +1699,12 @@ if ( ! function_exists( 'wp_notify_moderator' ) ) :
 
 		$switched_locale = switch_to_locale( get_locale() );
 
-		$comment_author_domain = @gethostbyaddr( $comment->comment_author_IP );
-		$comments_waiting      = $wpdb->get_var( "SELECT count(comment_ID) FROM $wpdb->comments WHERE comment_approved = '0'" );
+		$comment_author_domain = '';
+		if ( WP_Http::is_ip_address( $comment->comment_author_IP ) ) {
+			$comment_author_domain = gethostbyaddr( $comment->comment_author_IP );
+		}
+
+		$comments_waiting = $wpdb->get_var( "SELECT count(comment_ID) FROM $wpdb->comments WHERE comment_approved = '0'" );
 
 		// The blogname option is escaped with esc_html on the way into the database in sanitize_option
 		// we want to reverse this for the plain text arena of emails.
@@ -1810,7 +1817,7 @@ if ( ! function_exists( 'wp_notify_moderator' ) ) :
 		$message_headers = apply_filters( 'comment_moderation_headers', $message_headers, $comment_id );
 
 		foreach ( $emails as $email ) {
-			@wp_mail( $email, wp_specialchars_decode( $subject ), $notify_message, $message_headers );
+			wp_mail( $email, wp_specialchars_decode( $subject ), $notify_message, $message_headers );
 		}
 
 		if ( $switched_locale ) {
@@ -1947,7 +1954,7 @@ if ( ! function_exists( 'wp_new_user_notification' ) ) :
 			 */
 			$wp_new_user_notification_email_admin = apply_filters( 'wp_new_user_notification_email_admin', $wp_new_user_notification_email_admin, $user, $blogname );
 
-			@wp_mail(
+			wp_mail(
 				$wp_new_user_notification_email_admin['to'],
 				wp_specialchars_decode( sprintf( $wp_new_user_notification_email_admin['subject'], $blogname ) ),
 				$wp_new_user_notification_email_admin['message'],

src/wp-includes/rest-api/class-wp-rest-server.php

@@ -1279,19 +1279,7 @@ class WP_REST_Server {
 	 * @param string $key Header key.
 	 */
 	public function remove_header( $key ) {
-		if ( function_exists( 'header_remove' ) ) {
-			// In PHP 5.3+ there is a way to remove an already set header.
-			header_remove( $key );
-		} else {
-			// In PHP 5.2, send an empty header, but only as a last resort to
-			// override a header already sent.
-			foreach ( headers_list() as $header ) {
-				if ( 0 === stripos( $header, "$key:" ) ) {
-					$this->send_header( $key, '' );
-					break;
-				}
-			}
-		}
+		header_remove( $key );
 	}
 
 	/**

src/wp-includes/widgets.php

@@ -1493,7 +1493,7 @@ function wp_widget_rss_output( $rss, $args = array() ) {
 			$title = __( 'Untitled' );
 		}
 
-		$desc = @html_entity_decode( $item->get_description(), ENT_QUOTES, get_option( 'blog_charset' ) );
+		$desc = html_entity_decode( $item->get_description(), ENT_QUOTES, get_option( 'blog_charset' ) );
 		$desc = esc_attr( wp_trim_words( $desc, 55, ' […]' ) );
 
 		$summary = '';

src/wp-includes/widgets/class-wp-widget-rss.php

@@ -67,7 +67,7 @@ class WP_Widget_RSS extends WP_Widget {
 		$link  = '';
 
 		if ( ! is_wp_error( $rss ) ) {
-			$desc = esc_attr( strip_tags( @html_entity_decode( $rss->get_description(), ENT_QUOTES, get_option( 'blog_charset' ) ) ) );
+			$desc = esc_attr( strip_tags( html_entity_decode( $rss->get_description(), ENT_QUOTES, get_option( 'blog_charset' ) ) ) );
 			if ( empty( $title ) ) {
 				$title = strip_tags( $rss->get_title() );
 			}

src/wp-includes/widgets/class-wp-widget-text.php

@@ -123,6 +123,7 @@ class WP_Widget_Text extends WP_Widget {
 
 		// Suppress warnings generated by loadHTML
 		$errors = libxml_use_internal_errors( true );
+		// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged
 		@$doc->loadHTML(
 			sprintf(
 				'<!DOCTYPE html><html><head><meta charset="%s"></head><body>%s</body></html>',

src/wp-includes/wp-db.php

@@ -1376,7 +1376,7 @@ class wpdb {
 		}
 
 		array_walk( $args, array( $this, 'escape_by_ref' ) );
-		$query = @vsprintf( $query, $args );
+		$query = vsprintf( $query, $args );
 
 		return $this->add_placeholder_escape( $query );
 	}
@@ -1614,6 +1614,7 @@ class wpdb {
 			if ( WP_DEBUG ) {
 				mysqli_real_connect( $this->dbh, $host, $this->dbuser, $this->dbpassword, null, $port, $socket, $client_flags );
 			} else {
+				// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged
 				@mysqli_real_connect( $this->dbh, $host, $this->dbuser, $this->dbpassword, null, $port, $socket, $client_flags );
 			}
 
@@ -1645,6 +1646,7 @@ class wpdb {
 			if ( WP_DEBUG ) {
 				$this->dbh = mysql_connect( $this->dbhost, $this->dbuser, $this->dbpassword, $new_link, $client_flags );
 			} else {
+				// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged
 				$this->dbh = @mysql_connect( $this->dbhost, $this->dbuser, $this->dbpassword, $new_link, $client_flags );
 			}
 		}