Merge pull request #6 from mdmintz/context-manager-format

Add a context manager format

README.md

@@ -15,6 +15,14 @@ display.start()
 display.stop()
 ```
 
+### Or as a context manager:
+
+```python
+with Display(visible=0, size=(1440, 1880)):
+    # Run browser tests in a headless environment
+    ...
+```
+
 ## When to use:
 
 If you need to run browser tests on a headless machine (such as a Linux backend), and you can't use a browser's headless mode (such as Chrome's headless mode), then this may help. For example, Chrome does not allow extensions in headless mode, so if you need to run automated tests on a headless Linux machine and you need to use Chrome extensions, then this will let you run those tests using a virtual display.

sbvirtualdisplay/__version__.py

@@ -1,2 +1,2 @@
 # sbvirtualdisplay package
-__version__ = "1.1.1"
+__version__ = "1.2.0"

sbvirtualdisplay/abstractdisplay.py

@@ -95,6 +95,15 @@ def stop(self):
             self._clear_xauth()
         return self
 
+    def __enter__(self):
+        """Used by the :keyword:`with` statement"""
+        self.start()
+        return self
+
+    def __exit__(self, *exc_info):
+        """Used by the :keyword:`with` statement"""
+        self.stop()
+
     def _setup_xauth(self):
         """Set up the Xauthority file & the XAUTHORITY environment variable."""
         handle, filename = tempfile.mkstemp(