Ruleset: bug fix - correctly handle empty array property setting

While already handled correctly for inline properties set via `phpcs:set`, setting a property to an empty array from a ruleset file was not handled correctly until now.

As things were, when setting an array property from the ruleset to an empty array like so:
```xml
    <rule ref="Standard.Category.SniffName">
        <properties>
            <property name="arrayProperty" type="array"/>
        </properties>
    </rule>
```

 the property value would be set to:
```php
public $arrayProperty = [
    0 => '',
];
```
... while the expected behaviour would be:
```php
public $arrayProperty = [];
```

While it is not expected that this type of property setting is encountered a lot in the wild, it should still work correctly.

Fixed now.

Includes test safeguarding the fix.

Author: jrfnl

tests/Core/Ruleset/Fixtures/PropertyTypeHandlingInline.inc

@@ -21,10 +21,12 @@
 // phpcs:set TestStandard.SetProperty.PropertyTypeHandling expectsArrayWithKeysAndValues[] string=>string,10=>10,float=>1.5,null=>null,true=>true,false=>false
 // phpcs:set TestStandard.SetProperty.PropertyTypeHandling expectsArrayWithExtendedValues[] string, 15, another string
 // phpcs:set TestStandard.SetProperty.PropertyTypeHandling expectsArrayWithExtendedKeysAndValues[] 10=>10,string=>string,15=>15,another string=>another string
+// phpcs:set TestStandard.SetProperty.PropertyTypeHandling expectsEmptyArray[]
 
 // phpcs:set TestStandard.SetProperty.PropertyTypeHandling expectsOldSchoolArrayWithOnlyValues[] string, 10, 1.5, null, true, false
 // phpcs:set TestStandard.SetProperty.PropertyTypeHandling expectsOldSchoolArrayWithKeysAndValues[] string=>string,10=>10,float=>1.5,null=>null,true=>true,false=>false
 // phpcs:set TestStandard.SetProperty.PropertyTypeHandling expectsOldSchoolArrayWithExtendedValues[] string, 15, another string
 // phpcs:set TestStandard.SetProperty.PropertyTypeHandling expectsOldSchoolArrayWithExtendedKeysAndValues[] 10=>10,string=>string,15=>15,another string=>another string
+// phpcs:set TestStandard.SetProperty.PropertyTypeHandling expectsOldSchoolEmptyArray[]
 
 echo 'hello!';

tests/Core/Ruleset/Fixtures/TestStandard/Sniffs/SetProperty/PropertyTypeHandlingSniff.php

@@ -113,6 +113,13 @@ final class PropertyTypeHandlingSniff implements Sniff
      */
     public $expectsArrayWithExtendedKeysAndValues;
 
+    /**
+     * Used to verify that array properties allow for setting a property to an empty array.
+     *
+     * @var array<mixed>
+     */
+    public $expectsEmptyArray;
+
     /**
      * Used to verify that array properties passed as a string get parsed to a proper array.
      *
@@ -141,6 +148,13 @@ final class PropertyTypeHandlingSniff implements Sniff
      */
     public $expectsOldSchoolArrayWithExtendedKeysAndValues;
 
+    /**
+     * Used to verify that array properties passed as a string allow for setting a property to an empty array.
+     *
+     * @var array<mixed>
+     */
+    public $expectsOldSchoolEmptyArray;
+
     public function register()
     {
         return [T_ECHO];

tests/Core/Ruleset/PropertyTypeHandlingTest.php

@@ -171,7 +171,10 @@ public static function dataTypeHandling()
                 'propertyName' => 'expectsArrayWithExtendedKeysAndValues',
                 'expected'     => $expectedArrayKeysAndValuesExtended,
             ],
-
+            'Empty array'                                    => [
+                'propertyName' => 'expectsEmptyArray',
+                'expected'     => [],
+            ],
         ];
 
     }//end dataTypeHandling()

tests/Core/Ruleset/PropertyTypeHandlingTest.xml

@@ -53,6 +53,8 @@
                 <element key="15" value="15"/>
                 <element key="another string" value="another string"/>
             </property>
+
+            <property name="expectsEmptyArray" type="array"/>
         </properties>
     </rule>