Load: Ensure wp_using_ext_object_cache() always returns a boolean.

Author: liaisontw

src/wp-includes/load.php

@@ -808,20 +808,21 @@ function wp_set_wpdb_vars() {
  * @return bool The current 'using' setting.
  */
 function wp_using_ext_object_cache( $using = null ) {
-    global $_wp_using_ext_object_cache;
+	global $_wp_using_ext_object_cache;
 
-    // Save the current state to return later.
-    $current_using = $_wp_using_ext_object_cache;
+	// Save the current state to return later.
+	$current_using = $_wp_using_ext_object_cache;
 
-    if ( null !== $using ) {
-        $_wp_using_ext_object_cache = (bool) $using;
-    }
+	if ( null !== $using ) {
+		$_wp_using_ext_object_cache = (bool) $using;
+	}
+
+	if ( null === $_wp_using_ext_object_cache ) {
+		// If the global is uninitialized, the value would be null, which violates the type signature.
+		return false;
+	}
 
-    /**
-     * Ensure the returned value is always a boolean. 
-     * If the global is uninitialized, it could be null, which violates the type signature.
-     */
-    return (bool) $current_using;
+	return (bool) $current_using;
 }
 
 /**

tests/phpunit/tests/load/wpUsingExtObjectCache.php

@@ -0,0 +1,32 @@
+<?php
+
+/**
+ * Tests for wp_using_ext_object_cache().
+ *
+ * @group load
+ *
+ * @covers ::wp_using_ext_object_cache
+ */
+class Tests_Load_wpUsingExtObjectCache extends WP_UnitTestCase {
+
+	private $orig_using_ext_cache;
+
+	public function set_up() {
+		parent::set_up();
+		global $_wp_using_ext_object_cache;
+
+		$this->orig_using_ext_cache = $_wp_using_ext_object_cache;
+	}
+
+	public function tear_down() {
+		global $_wp_using_ext_object_cache;
+
+		$_wp_using_ext_object_cache = $this->orig_using_ext_cache;
+		parent::tear_down();
+	}
+
+	public function test_should_always_return_boolean() {
+		wp_using_ext_object_cache( 1 );
+		$this->assertIsBool( wp_using_ext_object_cache() );
+	}
+}