Implemented disabling of core updates.

readme.md

@@ -1,6 +1,6 @@
 # Update Blocker — for WP repositories
 
-Update Blocker is a lightweight generic blocker of plugin and theme updates from official WordPress repositories.
+Update Blocker is a lightweight generic blocker of plugin, theme, and core updates from official WordPress repositories.
 
 It was created as shared reusable plugin for the sake of no longer reinventing that particular wheel.
 
@@ -68,13 +68,15 @@ array(
 	'files'   => array( '.git', '.svn', '.hg' ),
 	'plugins' => array( 'update-blocker/update-blocker.php' ),
 	'themes'  => array(),
+	'core'    => false,
 )
 ```
 
  - `all` — boolean, disables updates completely
  - `files` — array of plugin/theme root–relative files to detect for block
  - `plugins` — array of plugin base names (`folder-name/plugin-name.php`) to block
  - `themes` — array of theme slugs (`theme-name`) to block
+ - `core` — boolean, disables core updates
 
 Settings pass through `update_blocker_blocked` filter.
 
@@ -98,6 +100,15 @@ add_filter( 'update_blocker_blocked', function( $blocked ) {
 } );
 ```
 
+### Core opt–in
+
+```php
+add_filter( 'update_blocker_blocked', function ( $blocked ) {
+	$blocked['core'] = true;
+	return $blocked;
+} );
+```
+
 ## License
 
  - MIT

update-blocker.php

@@ -35,6 +35,7 @@
 	'files'   => array( '.git', '.svn', '.hg' ),
 	'plugins' => array( 'update-blocker/update-blocker.php' ),
 	'themes'  => array(),
+	'core'    => false,
 ) );
 
 /**
@@ -55,7 +56,7 @@ public function __construct( $blocked = array() ) {
 		register_activation_hook( __FILE__, array( $this, 'delete_update_transients' ) );
 		register_deactivation_hook( __FILE__, array( $this, 'delete_update_transients' ) );
 
-		$defaults      = array( 'all' => false ) + array_fill_keys( array( 'files', 'plugins', 'themes' ), array() );
+		$defaults      = array( 'all' => false, 'core' => false ) + array_fill_keys( array( 'files', 'plugins', 'themes' ), array() );
 		$this->blocked = array_merge( $defaults, $blocked );
 
 		add_action( 'init', array( $this, 'init' ) );
@@ -72,6 +73,10 @@ public function init() {
 		} else {
 			add_filter( 'http_request_args', array( $this, 'http_request_args' ), 10, 2 );
 		}
+
+		if ( $this->blocked->all || $this->blocked->core ) {
+			add_filter( 'pre_site_transient_update_core', array( $this, 'return_empty_core_update' ) );
+		}
 	}
 
 	/**
@@ -240,4 +245,20 @@ public function has_blocked_file( $path ) {
 
 		return false;
 	}
+
+	/**
+	 * Returns faked empty results to short circuit core update check.
+	 *
+	 * @return object
+	 */
+	public function return_empty_core_update() {
+
+		global $wp_version;
+
+		return (object) array(
+			'updates'         => array(),
+			'version_checked' => $wp_version,
+			'last_checked'    => time(),
+		);
+	}
 }