Use strict comparison in various files

src/wp-admin/includes/class-wp-privacy-policy-content.php

@@ -107,7 +107,7 @@ public static function text_change_check() {
 		 * The == operator (equal, not identical) was used intentionally.
 		 * See https://www.php.net/manual/en/language.operators.array.php
 		 */
-		if ( $new != $old ) {
+		if ( $new != $old ) { // phpcs:ignore WordPress.PHP.StrictComparisons.LooseComparison
 			/*
 			 * A plugin was activated or deactivated, or some policy text has changed.
 			 * Show a notice on the relevant screens to inform the admin.

src/wp-admin/includes/media.php

@@ -93,7 +93,7 @@ function the_media_upload_tabs() {
 		foreach ( $tabs as $callback => $text ) {
 			$class = '';
 
-			if ( $current == $callback ) {
+			if ( $current === $callback ) {
 				$class = " class='current'";
 			}
 
@@ -807,7 +807,9 @@ function media_upload_form_handler() {
 				unset( $post['errors'] );
 			}
 
-			if ( $post != $_post ) {
+			// The == operator (equal, not identical) was used intentionally.
+			// See http://php.net/manual/en/language.operators.array.php
+			if ( $post != $_post ) { // phpcs:ignore WordPress.PHP.StrictComparisons.LooseComparison
 				wp_update_post( $post );
 			}
 
@@ -1172,7 +1174,7 @@ function image_align_input_fields( $post, $checked = '' ) {
 	foreach ( $alignments as $name => $label ) {
 		$name     = esc_attr( $name );
 		$output[] = "<input type='radio' name='attachments[{$post->ID}][align]' id='image-align-{$name}-{$post->ID}' value='$name'" .
-			( $checked == $name ? " checked='checked'" : '' ) .
+			( $checked === $name ? " checked='checked'" : '' ) .
 			" /><label for='image-align-{$name}-{$post->ID}' class='align image-align-{$name}-label'>$label</label>";
 	}
 
@@ -1222,7 +1224,7 @@ function image_size_input_fields( $post, $check = '' ) {
 		$css_id  = "image-size-{$size}-{$post->ID}";
 
 		// If this size is the default but that's not available, don't select it.
-		if ( $size == $check ) {
+		if ( $size === $check ) {
 			if ( $enabled ) {
 				$checked = " checked='checked'";
 			} else {
@@ -1762,7 +1764,7 @@ function get_media_item( $attachment_id, $args = null ) {
 	if ( 'image' === $type && $calling_post_id
 		&& current_theme_supports( 'post-thumbnails', get_post_type( $calling_post_id ) )
 		&& post_type_supports( get_post_type( $calling_post_id ), 'thumbnail' )
-		&& get_post_thumbnail_id( $calling_post_id ) != $attachment_id
+		&& get_post_thumbnail_id( $calling_post_id ) !== $attachment_id
 	) {
 
 		$calling_post             = get_post( $calling_post_id );
@@ -2853,20 +2855,20 @@ function media_upload_library_form( $errors ) {
 		$month_count    = count( $arc_result );
 		$selected_month = isset( $_GET['m'] ) ? $_GET['m'] : 0;
 
-		if ( $month_count && ! ( 1 == $month_count && 0 == $arc_result[0]->mmonth ) ) {
+		if ( $month_count && ! ( 1 === $month_count && 0 === (int) $arc_result[0]->mmonth ) ) {
 			?>
 			<select name='m'>
 			<option<?php selected( $selected_month, 0 ); ?> value='0'><?php _e( 'All dates' ); ?></option>
 			<?php
 
 			foreach ( $arc_result as $arc_row ) {
-				if ( 0 == $arc_row->yyear ) {
+				if ( 0 === (int) $arc_row->yyear ) {
 					continue;
 				}
 
 				$arc_row->mmonth = zeroise( $arc_row->mmonth, 2 );
 
-				if ( $arc_row->yyear . $arc_row->mmonth == $selected_month ) {
+				if ( (int) $arc_row->yyear . $arc_row->mmonth === (int) $selected_month ) {
 					$default = ' selected="selected"';
 				} else {
 					$default = '';

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

@@ -134,7 +134,7 @@ final class WP_Comment {
 	 * @since 4.4.0
 	 * @var string
 	 */
-	public $comment_parent = 0;
+	public $comment_parent = '0';
 
 	/**
 	 * Comment author ID.
@@ -144,7 +144,7 @@ final class WP_Comment {
 	 * @since 4.4.0
 	 * @var string
 	 */
-	public $user_id = 0;
+	public $user_id = '0';
 
 	/**
 	 * Comment children.

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

@@ -858,10 +858,10 @@ public function parse_query( $query = '' ) {
 		}
 
 		// Compat. Map subpost to attachment.
-		if ( is_scalar( $qv['subpost'] ) && '' != $qv['subpost'] ) {
+		if ( is_scalar( $qv['subpost'] ) && '' !== $qv['subpost'] ) {
 			$qv['attachment'] = $qv['subpost'];
 		}
-		if ( is_scalar( $qv['subpost_id'] ) && '' != $qv['subpost_id'] ) {
+		if ( is_scalar( $qv['subpost_id'] ) && '' !== $qv['subpost_id'] ) {
 			$qv['attachment_id'] = $qv['subpost_id'];
 		}
 
@@ -969,7 +969,7 @@ public function parse_query( $query = '' ) {
 			}
 			unset( $tax_query );
 
-			if ( empty( $qv['author'] ) || ( '0' == $qv['author'] ) ) {
+			if ( empty( $qv['author'] ) || ( '0' === (string) $qv['author'] ) ) {
 				$this->is_author = false;
 			} else {
 				$this->is_author = true;
@@ -991,24 +991,24 @@ public function parse_query( $query = '' ) {
 			}
 		}
 
-		if ( '' != $qv['feed'] ) {
+		if ( '' !== $qv['feed'] ) {
 			$this->is_feed = true;
 		}
 
-		if ( '' != $qv['embed'] ) {
+		if ( '' !== $qv['embed'] ) {
 			$this->is_embed = true;
 		}
 
-		if ( '' != $qv['tb'] ) {
+		if ( '' !== $qv['tb'] ) {
 			$this->is_trackback = true;
 		}
 
-		if ( '' != $qv['paged'] && ( (int) $qv['paged'] > 1 ) ) {
+		if ( '' !== $qv['paged'] && ( (int) $qv['paged'] > 1 ) ) {
 			$this->is_paged = true;
 		}
 
 		// If we're previewing inside the write screen.
-		if ( '' != $qv['preview'] ) {
+		if ( '' !== $qv['preview'] ) {
 			$this->is_preview = true;
 		}
 
@@ -1076,25 +1076,29 @@ public function parse_query( $query = '' ) {
 				unset( $this->queried_object );
 			}
 
-			if ( 'page' === get_option( 'show_on_front' ) && isset( $this->queried_object_id ) && get_option( 'page_for_posts' ) == $this->queried_object_id ) {
+			if ( 'page' === get_option( 'show_on_front' ) && isset( $this->queried_object_id )
+				&& (int) get_option( 'page_for_posts' ) === $this->queried_object_id
+			) {
 				$this->is_page       = false;
 				$this->is_home       = true;
 				$this->is_posts_page = true;
 			}
 
-			if ( isset( $this->queried_object_id ) && get_option( 'wp_page_for_privacy_policy' ) == $this->queried_object_id ) {
+			if ( isset( $this->queried_object_id )
+				&& (int) get_option( 'wp_page_for_privacy_policy' ) === $this->queried_object_id
+			) {
 				$this->is_privacy_policy = true;
 			}
 		}
 
 		if ( $qv['page_id'] ) {
-			if ( 'page' === get_option( 'show_on_front' ) && get_option( 'page_for_posts' ) == $qv['page_id'] ) {
+			if ( 'page' === get_option( 'show_on_front' ) && get_option( 'page_for_posts' ) === $qv['page_id'] ) {
 				$this->is_page       = false;
 				$this->is_home       = true;
 				$this->is_posts_page = true;
 			}
 
-			if ( get_option( 'wp_page_for_privacy_policy' ) == $qv['page_id'] ) {
+			if ( get_option( 'wp_page_for_privacy_policy' ) === $qv['page_id'] ) {
 				$this->is_privacy_policy = true;
 			}
 		}
@@ -1122,7 +1126,7 @@ public function parse_query( $query = '' ) {
 		$this->is_singular = $this->is_single || $this->is_page || $this->is_attachment;
 		// Done correcting `is_*` for 'page_on_front' and 'page_for_posts'.
 
-		if ( '404' == $qv['error'] ) {
+		if ( '404' === $qv['error'] ) {
 			$this->set_404();
 		}
 
@@ -1903,7 +1907,7 @@ public function get_posts() {
 
 		// Set a flag if a 'pre_get_posts' hook changed the query vars.
 		$hash = md5( serialize( $this->query_vars ) );
-		if ( $hash != $this->query_vars_hash ) {
+		if ( $hash !== $this->query_vars_hash ) {
 			$this->query_vars_changed = true;
 			$this->query_vars_hash    = $hash;
 		}
@@ -1983,11 +1987,12 @@ public function get_posts() {
 			$q['showposts']      = (int) $q['showposts'];
 			$q['posts_per_page'] = $q['showposts'];
 		}
-		if ( ( isset( $q['posts_per_archive_page'] ) && 0 != $q['posts_per_archive_page'] ) && ( $this->is_archive || $this->is_search ) ) {
+		if ( ( isset( $q['posts_per_archive_page'] ) && 0 !== (int) $q['posts_per_archive_page'] )
+			&& ( $this->is_archive || $this->is_search ) ) {
 			$q['posts_per_page'] = $q['posts_per_archive_page'];
 		}
 		if ( ! isset( $q['nopaging'] ) ) {
-			if ( -1 == $q['posts_per_page'] ) {
+			if ( -1 === (int) $q['posts_per_page'] ) {
 				$q['nopaging'] = true;
 			} else {
 				$q['nopaging'] = false;
@@ -2003,14 +2008,15 @@ public function get_posts() {
 			}
 			$q['nopaging'] = false;
 		}
+
 		$q['posts_per_page'] = (int) $q['posts_per_page'];
 		if ( $q['posts_per_page'] < -1 ) {
 			$q['posts_per_page'] = abs( $q['posts_per_page'] );
-		} elseif ( 0 == $q['posts_per_page'] ) {
+		} elseif ( 0 === $q['posts_per_page'] ) {
 			$q['posts_per_page'] = 1;
 		}
 
-		if ( ! isset( $q['comments_per_page'] ) || 0 == $q['comments_per_page'] ) {
+		if ( ! isset( $q['comments_per_page'] ) || 0 === (int) $q['comments_per_page'] ) {
 			$q['comments_per_page'] = get_option( 'comments_per_page' );
 		}
 
@@ -2166,8 +2172,8 @@ public function get_posts() {
 				}
 			}
 
-			$page_for_posts = get_option( 'page_for_posts' );
-			if ( ( 'page' !== get_option( 'show_on_front' ) ) || empty( $page_for_posts ) || ( $reqpage != $page_for_posts ) ) {
+			$page_for_posts = (int) get_option( 'page_for_posts' );
+			if ( ( 'page' !== get_option( 'show_on_front' ) ) || empty( $page_for_posts ) || ( $reqpage !== $page_for_posts ) ) {
 				$q['pagename'] = sanitize_title_for_query( wp_basename( $q['pagename'] ) );
 				$q['name']     = $q['pagename'];
 				$where        .= " AND ({$wpdb->posts}.ID = '$reqpage')";
@@ -2217,7 +2223,7 @@ public function get_posts() {
 		}
 
 		if ( $q['page_id'] ) {
-			if ( ( 'page' !== get_option( 'show_on_front' ) ) || ( get_option( 'page_for_posts' ) != $q['page_id'] ) ) {
+			if ( ( 'page' !== get_option( 'show_on_front' ) ) || ( get_option( 'page_for_posts' ) !== $q['page_id'] ) ) {
 				$q['p'] = $q['page_id'];
 				$where  = " AND {$wpdb->posts}.ID = " . $q['page_id'];
 			}
@@ -2338,7 +2344,7 @@ public function get_posts() {
 
 		// Author/user stuff.
 
-		if ( ! empty( $q['author'] ) && '0' != $q['author'] ) {
+		if ( ! empty( $q['author'] ) && 0 !== (int) $q['author'] ) {
 			$q['author'] = addslashes_gpc( '' . urldecode( $q['author'] ) );
 			$authors     = array_unique( array_map( 'intval', preg_split( '/[,\s]+/', $q['author'] ) ) );
 			foreach ( $authors as $author ) {
@@ -3295,7 +3301,7 @@ public function get_posts() {
 			return $post_parents;
 		}
 
-		$is_unfiltered_query = $old_request == $this->request && "{$wpdb->posts}.*" === $fields;
+		$is_unfiltered_query = $old_request === $this->request && "{$wpdb->posts}.*" === $fields;
 
 		if ( null === $this->posts ) {
 			$split_the_query = (
@@ -3701,7 +3707,7 @@ public function the_post() {
 		$this->in_the_loop = true;
 		$this->before_loop = false;
 
-		if ( -1 == $this->current_post ) { // Loop has just started.
+		if ( -1 === $this->current_post ) { // Loop has just started.
 			/**
 			 * Fires once the loop is started.
 			 *
@@ -3728,7 +3734,7 @@ public function the_post() {
 	public function have_posts() {
 		if ( $this->current_post + 1 < $this->post_count ) {
 			return true;
-		} elseif ( $this->current_post + 1 == $this->post_count && $this->post_count > 0 ) {
+		} elseif ( $this->current_post + 1 === $this->post_count && $this->post_count > 0 ) {
 			/**
 			 * Fires once the loop has ended.
 			 *
@@ -3795,7 +3801,7 @@ public function the_comment() {
 
 		$comment = $this->next_comment();
 
-		if ( 0 == $this->current_comment ) {
+		if ( 0 === $this->current_comment ) {
 			/**
 			 * Fires once the comment loop is started.
 			 *
@@ -3817,7 +3823,7 @@ public function the_comment() {
 	public function have_comments() {
 		if ( $this->current_comment + 1 < $this->comment_count ) {
 			return true;
-		} elseif ( $this->current_comment + 1 == $this->comment_count ) {
+		} elseif ( $this->current_comment + 1 === $this->comment_count ) {
 			$this->rewind_comments();
 		}
 
@@ -4484,7 +4490,7 @@ public function is_page( $page = '' ) {
 				}
 				$pagepath_obj = get_page_by_path( $pagepath );
 
-				if ( $pagepath_obj && ( $pagepath_obj->ID == $page_obj->ID ) ) {
+				if ( $pagepath_obj && ( $pagepath_obj->ID === $page_obj->ID ) ) {
 					return true;
 				}
 			}
@@ -4594,7 +4600,7 @@ public function is_single( $post = '' ) {
 				}
 				$postpath_obj = get_page_by_path( $postpath, OBJECT, $post_obj->post_type );
 
-				if ( $postpath_obj && ( $postpath_obj->ID == $post_obj->ID ) ) {
+				if ( $postpath_obj && ( $postpath_obj->ID === $post_obj->ID ) ) {
 					return true;
 				}
 			}