Everybody is welcome to contribute to OPAL and to submit pull requests. However, a pull request is only taken into consideration if you follow these guidelines. A recommended read (to speed up the process of getting your pull request pulled): The Twitter Scala Style Guide
A pull request w.r.t. the master branch will directly be rejected. Integration with the master branch is always only done after thorough testing by a core developer.
The link to the copyright information (BSD License) was added to the file at the very beginning (/* BSD 2-Clause License - see OPAL/LICENSE for details. */). This is an open-source project and we have to make sure that no one adds non open-source code. If you add other resources (icons etc.) to the project make sure that a license file is also found in the commit!
Author information was added where appropriate. It is important to be able to identify the author of some code to know where to get help/to know who is responsible.
All existing unit and integration tests were successfully executed. Sufficient tests for the new code are included (use Scalatest or ScalaCheck for the development and use scoverage for checking the coverage; the tests should check all features(!) and should have a coverage that is close to 100%.
The code is formatted using the same settings and style as the rest of the code; use the sbt compileAll command to ensure basic formatting!
The code is reasonably documented.
Ensure that the code conventions w.r.t. naming and formatting are followed.
Do not use Scala's feature to import multiple classes/objects from the same package using the corresponding syntax (e.g., import scala.collcation.immutable.{HashMap,LinkedList,Stack}). Using such imports does not play well with certain editors.
(This behavior can be configured in IntelliJ)
Do not used wildcard imports, e.g., import scala.collection._, unless you import a huge (> 48) number of classes for the same package. Such imports are very brittle and can lead to strange behavior.
(This behavior can be configured in IntelliJ)
Never reformat code that is not related to your task at hand; unless explicitly asked to do so. The commit should focus solely on your feature.