fix: Update return types of Implode and Unlines operation.

src/Contract/Operation/Implodeable.php

@@ -23,7 +23,7 @@ interface Implodeable
      *
      * @see https://loophp-collection.readthedocs.io/en/stable/pages/api.html#implode
      *
-     * @return Collection<int, string>
+     * @return Collection<TKey, string>
      */
     public function implode(string $glue = ''): Collection;
 }

src/Operation/Implode.php

@@ -26,13 +26,13 @@ final class Implode extends AbstractOperation
     /**
      * @pure
      *
-     * @return Closure(string): Closure(Iterator<TKey, T>): Generator<int, string>
+     * @return Closure(string): Closure(Iterator<TKey, T>): Generator<TKey, string>
      */
     public function __invoke(): Closure
     {
         return
             /**
-             * @return Closure(Iterator<TKey, T>): Generator<int, string>
+             * @return Closure(Iterator<TKey, T>): Generator<TKey, string>
              */
             static function (string $glue): Closure {
                 $reducer =
@@ -41,7 +41,7 @@ static function (string $glue): Closure {
                      */
                     static fn (string $carry, $item): string => $carry .= $item;
 
-                /** @var Closure(Iterator<TKey, T>): Generator<int, string> $pipe */
+                /** @var Closure(Iterator<TKey, T>): Generator<TKey, string> $pipe */
                 $pipe = Pipe::of()(
                     Intersperse::of()($glue)(1)(0),
                     Drop::of()(1),

src/Operation/Unlines.php

@@ -26,7 +26,7 @@ final class Unlines extends AbstractOperation
     /**
      * @pure
      *
-     * @return Closure(Iterator<TKey, (T|string)>): Generator<TKey, string, mixed, void>
+     * @return Closure(Iterator<TKey, (T|string)>): Generator<TKey, string>
      */
     public function __invoke(): Closure
     {

tests/static-analysis/implode.php

@@ -0,0 +1,32 @@
+<?php
+
+/**
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+include __DIR__ . '/../../vendor/autoload.php';
+
+use loophp\collection\Collection;
+use loophp\collection\Contract\Collection as CollectionInterface;
+
+/**
+ * @param CollectionInterface<int, string> $collection
+ */
+function implode_checkListString(CollectionInterface $collection): void
+{
+}
+
+/**
+ * @param CollectionInterface<string, string> $collection
+ */
+function implode_checkMapInt(CollectionInterface $collection): void
+{
+}
+
+$input = range('a', 'e');
+
+implode_checkListString(Collection::fromIterable($input)->implode(','));
+implode_checkMapInt(Collection::fromIterable(array_combine($input, $input))->implode(','));