Extract read-only part of Collection

docs/en/index.rst

@@ -32,6 +32,11 @@ explicitly retrieve an iterator though ``getIterator()`` which can then be
 used to iterate over the collection. You can not rely on the internal iterator
 of the collection being at a certain position unless you explicitly positioned it before.
 
+Methods that do not alter the collection or have template types
+appearing in invariant or contravariant positions are not directly
+defined in ``Doctrine\Common\Collections\Collection``, but are inherited
+from the ``Doctrine\Common\Collections\ReadableCollection`` interface.
+
 The methods available on the interface are:
 
 add

lib/Doctrine/Common/Collections/AbstractLazyCollection.php

@@ -61,6 +61,8 @@ public function clear()
 
     /**
      * {@inheritDoc}
+     *
+     * @template TMaybeContained
      */
     public function contains($element)
     {
@@ -260,6 +262,8 @@ public function partition(Closure $p)
 
     /**
      * {@inheritDoc}
+     *
+     * @template TMaybeContained
      */
     public function indexOf($element)
     {

lib/Doctrine/Common/Collections/ArrayCollection.php

@@ -231,6 +231,8 @@ public function containsKey($key)
 
     /**
      * {@inheritDoc}
+     *
+     * @template TMaybeContained
      */
     public function contains($element)
     {
@@ -253,6 +255,12 @@ public function exists(Closure $p)
 
     /**
      * {@inheritDoc}
+     *
+     * @psalm-param TMaybeContained $element
+     *
+     * @psalm-return (TMaybeContained is T ? TKey|false : false)
+     *
+     * @template TMaybeContained
      */
     public function indexOf($element)
     {

lib/Doctrine/Common/Collections/Collection.php

@@ -4,8 +4,6 @@
 
 use ArrayAccess;
 use Closure;
-use Countable;
-use IteratorAggregate;
 
 /**
  * The missing (SPL) Collection/Array/OrderedMap interface.
@@ -26,10 +24,10 @@
  *
  * @psalm-template TKey of array-key
  * @psalm-template T
- * @template-extends IteratorAggregate<TKey, T>
+ * @template-extends ReadableCollection<TKey, T>
  * @template-extends ArrayAccess<TKey, T>
  */
-interface Collection extends Countable, IteratorAggregate, ArrayAccess
+interface Collection extends ReadableCollection, ArrayAccess
 {
     /**
      * Adds an element at the end of the collection.
@@ -48,24 +46,6 @@ public function add($element);
      */
     public function clear();
 
-    /**
-     * Checks whether an element is contained in the collection.
-     * This is an O(n) operation, where n is the size of the collection.
-     *
-     * @param mixed $element The element to search for.
-     * @psalm-param T $element
-     *
-     * @return bool TRUE if the collection contains the element, FALSE otherwise.
-     */
-    public function contains($element);
-
-    /**
-     * Checks whether the collection is empty (contains no elements).
-     *
-     * @return bool TRUE if the collection is empty, FALSE otherwise.
-     */
-    public function isEmpty();
-
     /**
      * Removes the element at the specified index from the collection.
      *
@@ -87,46 +67,6 @@ public function remove($key);
      */
     public function removeElement($element);
 
-    /**
-     * Checks whether the collection contains an element with the specified key/index.
-     *
-     * @param string|int $key The key/index to check for.
-     * @psalm-param TKey $key
-     *
-     * @return bool TRUE if the collection contains an element with the specified key/index,
-     *              FALSE otherwise.
-     */
-    public function containsKey($key);
-
-    /**
-     * Gets the element at the specified key/index.
-     *
-     * @param string|int $key The key/index of the element to retrieve.
-     * @psalm-param TKey $key
-     *
-     * @return mixed
-     * @psalm-return T|null
-     */
-    public function get($key);
-
-    /**
-     * Gets all keys/indices of the collection.
-     *
-     * @return int[]|string[] The keys/indices of the collection, in the order of the corresponding
-     *               elements in the collection.
-     * @psalm-return TKey[]
-     */
-    public function getKeys();
-
-    /**
-     * Gets all values of the collection.
-     *
-     * @return mixed[] The values of all elements in the collection, in the
-     *                 order they appear in the collection.
-     * @psalm-return list<T>
-     */
-    public function getValues();
-
     /**
      * Sets an element in the collection at the specified key/index.
      *
@@ -140,137 +80,20 @@ public function getValues();
     public function set($key, $value);
 
     /**
-     * Gets a native PHP array representation of the collection.
-     *
-     * @return mixed[]
-     * @psalm-return array<TKey,T>
-     */
-    public function toArray();
-
-    /**
-     * Sets the internal iterator to the first element in the collection and returns this element.
-     *
-     * @return mixed
-     * @psalm-return T|false
-     */
-    public function first();
-
-    /**
-     * Sets the internal iterator to the last element in the collection and returns this element.
-     *
-     * @return mixed
-     * @psalm-return T|false
-     */
-    public function last();
-
-    /**
-     * Gets the key/index of the element at the current iterator position.
-     *
-     * @return int|string|null
-     * @psalm-return TKey|null
-     */
-    public function key();
-
-    /**
-     * Gets the element of the collection at the current iterator position.
-     *
-     * @return mixed
-     * @psalm-return T|false
-     */
-    public function current();
-
-    /**
-     * Moves the internal iterator position to the next element and returns this element.
-     *
-     * @return mixed
-     * @psalm-return T|false
-     */
-    public function next();
-
-    /**
-     * Tests for the existence of an element that satisfies the given predicate.
-     *
-     * @param Closure $p The predicate.
-     * @psalm-param Closure(TKey, T):bool $p
-     *
-     * @return bool TRUE if the predicate is TRUE for at least one element, FALSE otherwise.
-     */
-    public function exists(Closure $p);
-
-    /**
-     * Returns all the elements of this collection that satisfy the predicate p.
-     * The order of the elements is preserved.
-     *
-     * @param Closure $p The predicate used for filtering.
-     * @psalm-param Closure(T):bool $p
+     * {@inheritdoc}
      *
      * @return Collection<mixed> A collection with the results of the filter operation.
      * @psalm-return Collection<TKey, T>
      */
     public function filter(Closure $p);
 
     /**
-     * Tests whether the given predicate p holds for all elements of this collection.
-     *
-     * @param Closure $p The predicate.
-     * @psalm-param Closure(TKey, T):bool $p
-     *
-     * @return bool TRUE, if the predicate yields TRUE for all elements, FALSE otherwise.
-     */
-    public function forAll(Closure $p);
-
-    /**
-     * Applies the given function to each element in the collection and returns
-     * a new collection with the elements returned by the function.
-     *
-     * @psalm-param Closure(T):U $func
-     *
-     * @return Collection<mixed>
-     * @psalm-return Collection<TKey, U>
-     *
-     * @psalm-template U
-     */
-    public function map(Closure $func);
-
-    /**
-     * Partitions this collection in two collections according to a predicate.
-     * Keys are preserved in the resulting collections.
-     *
-     * @param Closure $p The predicate on which to partition.
-     * @psalm-param Closure(TKey, T):bool $p
+     * {@inheritdoc}
      *
      * @return Collection<mixed>[] An array with two elements. The first element contains the collection
      *                      of elements where the predicate returned TRUE, the second element
      *                      contains the collection of elements where the predicate returned FALSE.
      * @psalm-return array{0: Collection<TKey, T>, 1: Collection<TKey, T>}
      */
     public function partition(Closure $p);
-
-    /**
-     * Gets the index/key of a given element. The comparison of two elements is strict,
-     * that means not only the value but also the type must match.
-     * For objects this means reference equality.
-     *
-     * @param mixed $element The element to search for.
-     * @psalm-param T $element
-     *
-     * @return int|string|bool The key/index of the element or FALSE if the element was not found.
-     * @psalm-return TKey|false
-     */
-    public function indexOf($element);
-
-    /**
-     * Extracts a slice of $length elements starting at position $offset from the Collection.
-     *
-     * If $length is null it returns all elements from $offset to the end of the Collection.
-     * Keys have to be preserved by this method. Calling this method will only return the
-     * selected slice and NOT change the elements contained in the collection slice is called on.
-     *
-     * @param int      $offset The offset to start from.
-     * @param int|null $length The maximum number of elements to return, or null for no limit.
-     *
-     * @return mixed[]
-     * @psalm-return array<TKey,T>
-     */
-    public function slice($offset, $length = null);
 }