Missing comments on property metadata

Author: abluchet

src/Metadata/Property/PropertyMetadata.php

@@ -305,6 +305,23 @@ public function withAttributes(array $attributes): self
         return $metadata;
     }
 
+    /**
+     * Gets an attribute.
+     *
+     * @param string $key
+     * @param mixed  $defaultValue
+     *
+     * @return mixed
+     */
+    public function getAttribute(string $key, $defaultValue = null)
+    {
+        if (isset($this->attributes[$key])) {
+            return $this->attributes[$key];
+        }
+
+        return $defaultValue;
+    }
+
     /**
      * Is the property inherited from a child class?
      *
@@ -330,11 +347,23 @@ public function withChildInherited(string $childInherited): self
         return $metadata;
     }
 
+    /**
+     * Does the property have a subresource?
+     *
+     * @return bool|null
+     */
     public function hasSubresource()
     {
         return $this->subresource;
     }
 
+    /**
+     * Returns a new instance with the given subresource flag.
+     *
+     * @param bool $subresource
+     *
+     * @return self
+     */
     public function withSubresource(bool $subresource = null): self
     {
         $metadata = clone $this;