Start writing tests... (#7)

* Add astropy-helpers

* Add some of the dependencies

* Add an __all__

* Change opencv to opencv-python

* Fix up a bunch of the tests

* Make a couple of fixes uncovered by the tests

* Make license more visible

* Skip doctests for now

* Add dependencies on travis

* Drop osx test for now

* Use histogram autocut in test because median was not working on travis

* Use build stages to run tests on travis

* Add sphinx-astropy to Travis doc build

* Update helpers to master

* Fix helpers submodule

* Add egg-info tests to intial set of tests

* Remove the wrong helpers

* Change links to literals in docstrings

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "astropy_helpers"]
+	path = astropy_helpers
+	url = https://github.com/astropy/astropy-helpers.git

.travis.yml

@@ -38,7 +38,7 @@ env:
 
         # List other runtime dependencies for the package that are available as
         # conda packages here.
-        - CONDA_DEPENDENCIES=''
+        - CONDA_DEPENDENCIES='ginga ipyevents pillow opencv-python'
 
         # List other runtime dependencies for the package that are available as
         # pip packages here.
@@ -55,62 +55,70 @@ env:
         # line to use the X virtual framebuffer.
         # - SETUP_XVFB=True
 
-    matrix:
-        # Make sure that egg_info works without dependencies
-        - PYTHON_VERSION=3.5 SETUP_CMD='egg_info'
-        - PYTHON_VERSION=3.6 SETUP_CMD='egg_info'
-
+stages:
+   - name: Initial tests
+   - name: Comprehensive tests
+   - name: Cron tests
+     if: type = cron
 
 matrix:
 
     # Don't wait for allowed failures
     fast_finish: true
 
     include:
-        # Try MacOS X
-        - os: osx
-          env: SETUP_CMD='test'
+        - stage: Initial tests
+          env: PYTHON_VERSION=3.5 SETUP_CMD='egg_info'
+        - stage: Initial tests
+          env: PYTHON_VERSION=3.6 SETUP_CMD='egg_info'
+        - stage: Initial tests
+          env: PYTHON_VERSION=3.7 SETUP_CMD='egg_info'
 
         # Do a coverage test.
-        - os: linux
+        - stage: Initial tests
           env: SETUP_CMD='test --coverage'
 
         # Check for sphinx doc build warnings - we do this first because it
         # may run for a long time
-        - os: linux
+        - stage: Comprehensive tests
           env: SETUP_CMD='build_docs -w'
+               PIP_DEPENDENCIES='sphinx-astropy'
 
-        # Now try Astropy dev with the latest Python and LTS with Python 2.7 and 3.x.
-        - os: linux
+        # Now try Astropy dev with the latest Python and LTS with Python 3.x.
+        - stage: Comprehensive tests
           env: ASTROPY_VERSION=development
                EVENT_TYPE='pull_request push cron'
-        - os: linux
+        - stage: Comprehensive tests
           env: ASTROPY_VERSION=lts
 
         # Try all python versions and Numpy versions. Since we can assume that
         # the Numpy developers have taken care of testing Numpy with different
         # versions of Python, we can vary Python and Numpy versions at the same
         # time.
 
-        - os: linux
+        - stage: Comprehensive tests
           env: PYTHON_VERSION=3.5 NUMPY_VERSION=1.13
-        - os: linux
+        - stage: Comprehensive tests
           env: NUMPY_VERSION=1.14
 
         # Try numpy pre-release
-        - os: linux
+        - stage: Comprehensive tests
           env: NUMPY_VERSION=prerelease
                EVENT_TYPE='pull_request push cron'
 
         # Do a PEP8 test with pycodestyle
-        - os: linux
+        - stage: Comprehensive tests
           env: MAIN_CMD='pycodestyle astrowidgets --count' SETUP_CMD=''
 
+        # Try MacOS X
+        - stage: Cron tests
+          os: osx
+          env: SETUP_CMD='test'
+
     allow_failures:
         # Do a PEP8 test with pycodestyle
         # (allow to fail unless your code completely compliant)
-        - os: linux
-          env: MAIN_CMD='pycodestyle astrowidgets --count' SETUP_CMD=''
+        - env: MAIN_CMD='pycodestyle astrowidgets --count' SETUP_CMD=''
 
 install: