ReSharper automatically detects MSTest and NUnit tests in your projects.
After you build a project, ReSharper populates Unit Test Explorer with the list of tests that it has detected in the project.
In the editor, next to declarations of test classes and single tests, ReSharper adds special icons on the left gutter of the editor window. You can click these icons to run or debug tests .
|Test class declaration||
If the Enable action bar for action indicators and show it next to the left margin check box is selected on the Editor Appearance page of the Options dialog box, unit tests specific actions are combined with quick-fixes, context actions, etc. on the left gutter.