added travis ci and basic testing

.travis.yml

@@ -0,0 +1,15 @@
+sudo: false
+language: python
+python:
+  - "2.7"
+  - "3.5"
+  - "3.6"
+  - "3.7"
+
+# install dependencies
+install:
+  - pip install -r requirements.txt
+
+# run tests
+script:
+  - python -m pytest

requirements.txt

@@ -0,0 +1,3 @@
+numpy
+imageio
+vtk

tests/test_plotting.py

@@ -0,0 +1,15 @@
+import vtkInterface as vtki
+from vtkInterface import examples
+
+def RunningXServer():
+    """ Check if x server is running """
+    if os.name != 'posix':  # linux or mac os
+        raise Exception('Can only check x server on POSIX')
+    p = Popen(["xset", "-q"], stdout=PIPE, stderr=PIPE)
+    p.communicate()
+    return p.returncode == 0
+
+# we're getting there
+# def test_offscreen():
+#     sphere = examples.LoadSphere()
+#     sphere.Plot(off_screen=True)

tests/test_polydata.py

@@ -0,0 +1,16 @@
+import numpy as np
+import vtkInterface as vtki
+from vtkInterface import examples
+spherefile = examples.spherefile
+
+class TestPolyData(object):
+    # sphere = vtki.PolyData(spherefile)
+
+    def test_loadfromfile(self):
+        sphere = vtki.PolyData(spherefile)
+        assert sphere.GetNumberOfPoints()
+        assert sphere.GetNumberOfCells()
+        assert hasattr(sphere, 'points')
+
+# self = TestPolyData()
+# self.test_loadfromfile()

vtkInterface/plotting.py

@@ -3,7 +3,7 @@
 
 """
 from subprocess import Popen, PIPE
-
+import os
 from multiprocessing import Process
 import colorsys
 import numpy as np