gem module supports prerelease (--pre)

packaging/gem

@@ -67,6 +67,12 @@ options:
     description:
       - Version of the gem to be installed/removed.
     required: false
+  prerelease:
+    description:
+      - Allow installation of prerelease versions of the gem.
+    required: false
+    default: "no"
+    version_added: "1.6"
 author: Johan Wiren
 '''
 
@@ -174,6 +180,8 @@ def install(module):
         cmd.append('--user-install')
     else:
         cmd.append('--no-user-install')
+    if module.params['prerelease']:
+        cmd.append('--pre')
     cmd.append('--no-rdoc')
     cmd.append('--no-ri')
     cmd.append(module.params['gem_source'])
@@ -190,6 +198,7 @@ def main():
             repository           = dict(required=False, aliases=['source'], type='str'),
             state                = dict(required=False, default='present', choices=['present','absent','latest'], type='str'),
             user_install         = dict(required=False, default=True, type='bool'),
+            prerelease           = dict(required=False, default=False, type='bool'),
             version              = dict(required=False, type='str'),
         ),
         supports_check_mode = True,