Add self tests for gyp_to_android.

tools/tests/gyp_to_android_tests.py

Index: tools/tests/gyp_to_android_tests.py
diff --git a/tools/tests/gyp_to_android_tests.py b/tools/tests/gyp_to_android_tests.py
new file mode 100644
index 0000000000000000000000000000000000000000..dcd874e37c1ae7d5d67a97ac49d7d4e75724cc9c
--- /dev/null
+++ b/tools/tests/gyp_to_android_tests.py
@@ -0,0 +1,102 @@
+#!/usr/bin/python
+
+# Copyright 2014 Google Inc.
+#
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""
+Test gyp_to_android.py
+"""
+
+import os
+import sys
+
+# Find this file so we can find the Skia trunk.
+script_dir = os.path.dirname(__file__)

[epoger, 2014/01/21 20:00:51]

all caps for these constants

[scroggo, 2014/01/22 16:36:48]

Done.

+skia_trunk = os.path.normpath(os.path.join(script_dir, os.pardir, os.pardir))
+
+# Path to gyp_to_android
+sys.path.append(os.path.join('platform_tools', 'android', 'bin'))

[epoger, 2014/01/21 20:00:51]

It worries me that tools/ is running the unittests for platform_tools/ .

I think it would make more sense for platform_tools to get its own test_all.py
(copy it in from
https://code.google.com/p/skia/source/browse/trunk/gm/rebaseline_server/test_...
, which knows how to run all *_tests.py for you automatically, assuming that
they extend unittest.TestCase)

I would be OK with this rearrangement being a TODO...

[scroggo, 2014/01/22 16:36:48]

I've added a TODO. I think it's fine to move it inside this CL, but I'll leave
it here until you're happy with it so it will be easier to see what has changed
from patch set to patch set.

+
+import gyp_to_android
+
+def AssertFunctionAsserts(f):

[epoger, 2014/01/21 20:00:51]

Please make the self-test extend unittest.TestCase, like
https://code.google.com/p/skia/source/browse/trunk/gm/rebaseline_server/resul...

Among other things, it gives you
http://docs.python.org/2/library/unittest.html#unittest.TestCase.assertRaises ,
so you don't have to roll your own.

Again, I'm OK with this being a TODO.

[scroggo, 2014/01/22 16:36:48]

Done.

+  """
+  Assert that the passed in function asserts.
+  """
+  try:
+    f()
+  except AssertionError:
+    # Nothing to see here; this is the intended behavior.
+    pass
+  else:
+    assert False
+
+def TestVarsDict():
+  """
+  Tests for the VarsDict class.
+  """
+  vars_dict = gyp_to_android.VarsDict()

[epoger, 2014/01/21 20:00:51]

Using unittest.TestCase and its assertRaises() will make this function much more
compact, and easier to read.

vars_dict = gyp_to_android.VarsDict()
with self.assertRaises(AssertionError):
  vars_dict['c'] = None

...etc.

[scroggo, 2014/01/22 16:36:48]

Done.

+
+  # Inserting new dictionary entries should throw an exception.
+  def f():
+    vars_dict['c'] = None
+
+  AssertFunctionAsserts(f)
+
+  # ConvertDefines() should append all 'defines' to 'cflags' with '-D'.

[epoger, 2014/01/21 20:00:51]

When you convert this to unittest.TestCase, I think this is the start of a
separate test case.

[scroggo, 2014/01/22 16:36:48]

Done.

+
+  # 'cflags' starts off empty.
+  assert len(vars_dict['cflags']) == 0
+
+  vars_dict['defines'].extend(['foo', 'bar', 'c++'])
+
+  vars_dict.ConvertDefines()
+
+  assert len(vars_dict['cflags']) == len(vars_dict['defines'])
+
+  for define in vars_dict['defines']:
+    assert ('-D' + define) in vars_dict['cflags']
+
+  # ConvertDefines() can only be called once.
+  def g():
+    vars_dict.ConvertDefines()
+
+  AssertFunctionAsserts(g)
+
+def TestAddToList():
+  li = []
+  foo = 'foo'
+  gyp_to_android.AddToList(li, foo)
+  assert len(li) == 1
+  assert li[0] == foo
+
+  # Now attempt to add it again
+  gyp_to_android.AddToList(li, foo)
+  assert len(li) == 1
+  assert li[0] == foo
+
+def TestAndroidMkCreation():
+  if gyp_to_android.main() != 0:
+    raise Exception('gyp_to_android failed!')
+  # Now there should be a file named 'Android.mk' at the root level.
+  path_to_android_mk = os.path.join(skia_trunk, 'Android.mk')

[epoger, 2014/01/21 20:00:51]

I think it's dangerous for unittests to write into the real checkout.  I think
it would be much better to use
http://docs.python.org/2/library/tempfile.html#tempfile.mkdtemp to create a
temporary dir, and make gyp_to_android write into there (if possible).

[scroggo, 2014/01/22 16:36:48]

Done.

For what it's worth, gyp_to_android calls gyp in a way that gyp writes into
gyp/. I've tried changing it, but without changing gyp itself (which may be
possible), or using python to copy and modify the gyp files, it will write into
gyp/ regardless.

[scroggo, 2014/01/22 19:32:50]

Actually it wasn't so hard. In patch set 5 (and beyond), I copy the gyp files to
a new folder, so the gypd files are created in that file and later removed.

+  if not os.path.exists(path_to_android_mk):
+    raise Exception('Failed to create Android.mk!')
+  # Remove Android.mk, which is no longer needed.
+  os.remove(path_to_android_mk)
+
+  # gypd files should have been removed.
+  for filename in os.listdir(os.path.join(skia_trunk, 'gyp')):
+    assert not filename.endswith('gypd')
+
+def main():
+  print 'Running gyp_to_android tests...'
+  TestAndroidMkCreation()
+  TestVarsDict()
+  TestAddToList()
+  print 'gyp_to_android tests succeeded!'
+
+if __name__ == "__main__":
+  main()