Add `toPairs()` and `toCollection()`.

src/collections_methods.c

@@ -17,7 +17,8 @@
 #define NEW_COLLECTION_OBJ(name) \
     NEW_OBJ(name, collections_collection_ce, collection_handlers)
 #define NEW_PAIR_OBJ(name) \
-    NEW_OBJ(name, collections_pair_ce, &std_object_handlers)
+    NEW_OBJ(name, collections_pair_ce, &std_object_handlers); \
+    object_properties_init(name, collections_pair_ce)
 
 #define IS_COLLECTION_P(zval) \
     Z_TYPE_P(zval) == IS_OBJECT && Z_OBJCE_P(zval) == collections_collection_ce
@@ -1142,12 +1143,39 @@ PHP_METHOD(Collection, toArray)
 
 PHP_METHOD(Collection, toCollection)
 {
-    
+    zval* dest;
+    ZEND_PARSE_PARAMETERS_START(1, 1)
+        Z_PARAM_OBJECT_OF_CLASS(dest, collections_collection_ce)
+    ZEND_PARSE_PARAMETERS_END();
+    zend_array* current = COLLECTION_FETCH_EX();
+    zend_array* dest_arr = COLLECTION_FETCH(dest);
+    SEPARATE_COLLECTION(dest_arr, dest);
+    ZEND_HASH_FOREACH_BUCKET(current, Bucket* bucket)
+        if (bucket->key)
+            zend_hash_add(dest_arr, bucket->key, &bucket->val);
+        else
+            zend_hash_next_index_insert(dest_arr, &bucket->val);
+    ZEND_HASH_FOREACH_END();
+    RETVAL_ZVAL(dest, 1, 0);
 }
 
 PHP_METHOD(Collection, toPairs)
 {
-    
+    zend_array* current = COLLECTION_FETCH_EX();
+    ARRAY_NEW_EX(new_collection, current);
+    ZEND_HASH_FOREACH_BUCKET(current, Bucket* bucket)
+        NEW_PAIR_OBJ(obj);
+        zval pair, key;
+        ZVAL_OBJ(&pair, obj);
+        if (bucket->key)
+            ZVAL_STR(&key, bucket->key);
+        else
+            ZVAL_LONG(&key, bucket->h);
+        PAIR_UPDATE_FIRST(&pair, &key);
+        PAIR_UPDATE_SECOND(&pair, &bucket->val);
+        zend_hash_next_index_insert(new_collection, &pair);
+    ZEND_HASH_FOREACH_END();
+    RETVAL_NEW_COLLECTION(new_collection);
 }
 
 PHP_METHOD(Collection, union)

tests/020-to-collection.phpt

@@ -0,0 +1,10 @@
+--TEST--
+Test Collection::toCollection().
+--FILE--
+<?php
+$collection = Collection::init(['a', 'b']);
+Collection::init(['foo', 'bar'])->toCollection($collection);
+if ($collection->toArray() != ['a', 'b', 'foo', 'bar'])
+    echo 'Collection::toCollection() failed.', PHP_EOL;
+?>
+--EXPECT--

tests/021-to-pairs.phpt

@@ -0,0 +1,12 @@
+--TEST--
+Test Collection::toPairs().
+--FILE--
+<?php
+$pairs = Collection::init(['a' => 'b', 'c' => 'd'])->toPairs();
+$test = '';
+foreach ($pairs as $pair)
+    $test .= $pair->first . ',' . $pair->second . ';';
+if ($test != 'a,b;c,d;')
+    echo 'Collection::toPairs() failed.', PHP_EOL;
+?>
+--EXPECT--