diff --git a/src/Core/Configure/ConfigEngineInterface.php b/src/Core/Configure/ConfigEngineInterface.php
index 225912d6c0d..c413068db46 100644
--- a/src/Core/Configure/ConfigEngineInterface.php
+++ b/src/Core/Configure/ConfigEngineInterface.php
@@ -36,6 +36,6 @@ public function read($key);
  * @param array $data The data to dump.
  * @return bool True on success or false on failure.
  */
-	public function dump($key, $data);
+	public function dump($key, array $data);
 
 }
diff --git a/src/Core/Configure/Engine/IniConfig.php b/src/Core/Configure/Engine/IniConfig.php
index baf1c39bfab..20b2e7d0a48 100644
--- a/src/Core/Configure/Engine/IniConfig.php
+++ b/src/Core/Configure/Engine/IniConfig.php
@@ -72,12 +72,12 @@ class IniConfig implements ConfigEngineInterface {
  * Build and construct a new ini file parser. The parser can be used to read
  * ini files that are on the filesystem.
  *
- * @param string $path Path to load ini config files from. Defaults to CONFIG.
- * @param string $section Only get one section, leave null to parse and fetch
+ * @param string|null $path Path to load ini config files from. Defaults to CONFIG.
+ * @param string|null $section Only get one section, leave null to parse and fetch
  *     all sections in the ini file.
  */
 	public function __construct($path = null, $section = null) {
-		if (!$path) {
+		if ($path === null) {
 			$path = CONFIG;
 		}
 		$this->_path = $path;
@@ -154,7 +154,7 @@ protected function _parseNestedValues($values) {
  * @param array $data The data to convert to ini file.
  * @return int Bytes saved.
  */
-	public function dump($key, $data) {
+	public function dump($key, array $data) {
 		$result = array();
 		foreach ($data as $k => $value) {
 			$isSection = false;
diff --git a/src/Core/Configure/Engine/PhpConfig.php b/src/Core/Configure/Engine/PhpConfig.php
index 4f8350c95ba..6670f22a59e 100644
--- a/src/Core/Configure/Engine/PhpConfig.php
+++ b/src/Core/Configure/Engine/PhpConfig.php
@@ -37,10 +37,10 @@ class PhpConfig implements ConfigEngineInterface {
 /**
  * Constructor for PHP Config file reading.
  *
- * @param string $path The path to read config files from. Defaults to CONFIG.
+ * @param string|null $path The path to read config files from. Defaults to CONFIG.
  */
 	public function __construct($path = null) {
-		if (!$path) {
+		if ($path === null) {
 			$path = CONFIG;
 		}
 		$this->_path = $path;
@@ -84,7 +84,7 @@ public function read($key) {
  * @param array $data Data to dump.
  * @return int Bytes saved.
  */
-	public function dump($key, $data) {
+	public function dump($key, array $data) {
 		$contents = '<?php' . "\n" . '$config = ' . var_export($data, true) . ';';
 
 		$filename = $this->_getFilePath($key);