[11.4] Add "revert a commit" (#624)

Co-authored-by: Graham Campbell <GrahamCampbell@users.noreply.github.com>

Author: MoogyG

src/Api/Repositories.php

@@ -329,6 +329,20 @@ public function createCommit($project_id, array $parameters = [])
         return $this->post($this->getProjectPath($project_id, 'repository/commits'), $resolver->resolve($parameters));
     }
 
+    /**
+     * @param int|string $project_id
+     * @param string     $branch
+     * @param string     $sha
+     *
+     * @return mixed
+     */
+    public function revertCommit($project_id, string $branch, string $sha)
+    {
+        return $this->post($this->getProjectPath($project_id, 'repository/commits/'.self::encodePath($sha).'/revert'), [
+            'branch' => $branch,
+        ]);
+    }
+
     /**
      * @param int|string $project_id
      * @param string     $sha

tests/Api/RepositoriesTest.php

@@ -428,6 +428,23 @@ public function shouldCreateCommit(): void
         ]));
     }
 
+    /**
+     * @test
+     */
+    public function shouldRevertCommit(): void
+    {
+        $expectedArray = ['title' => 'Initial commit.', 'author_name' => 'John Doe', 'author_email' => 'john@example.com'];
+
+        $api = $this->getApiMock();
+        $api->expects($this->once())
+            ->method('post')
+            ->with('projects/1/repository/commits/abcd1234/revert')
+            ->will($this->returnValue($expectedArray))
+        ;
+
+        $this->assertEquals($expectedArray, $api->revertCommit(1, 'develop', 'abcd1234'));
+    }
+
     /**
      * @test
      */