Add tests for makefile_writer.py.

platform_tools/android/tests/makefile_writer_tests.py

Index: platform_tools/android/tests/makefile_writer_tests.py
diff --git a/platform_tools/android/tests/makefile_writer_tests.py b/platform_tools/android/tests/makefile_writer_tests.py
new file mode 100644
index 0000000000000000000000000000000000000000..9a764b5c0500526cb42210936ee88d3c54fdd36b
--- /dev/null
+++ b/platform_tools/android/tests/makefile_writer_tests.py
@@ -0,0 +1,198 @@
+#!/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 makefile_writer.py
+"""
+
+import argparse
+import os
+import shutil
+import sys
+import tempfile
+import test_variables
+import unittest
+
+sys.path.append(test_variables.GYP_GEN_DIR)
+
+import makefile_writer
+import vars_dict_lib
+
+EXPECTATIONS_DIR = os.path.join(os.path.dirname(__file__), 'expectations')
+MAKEFILE_NAME = 'Android.mk'
+
+def generate_dummy_vars_dict(name):
+  """Create a VarsDict and fill it with dummy entries.
+
+  Args:
+      name: string to be appended to each entry, if not None.
+
+  Returns:
+      A VarsDict with dummy entries.
+  """
+  vars_dict = vars_dict_lib.VarsDict()
+  for key in vars_dict.keys():
+    entry = key.lower()
+    if name:
+      entry += '_' + name
+    vars_dict[key].add(entry)
+  return vars_dict
+
+
+def generate_dummy_vars_dict_data(name, condition):
+  """Create a dummy VarsDictData.
+
+  Create a dummy VarsDictData, using the name for both the contained
+  VarsDict and the VarsDictData
+
+  Args:
+      name: name used by both the returned VarsDictData and its contained
+          VarsDict.
+      condition: condition used by the returned VarsDictData.
+
+  Returns:
+      A VarsDictData with dummy values, using the passed in info.
+  """
+  vars_dict = generate_dummy_vars_dict(name)
+
+  return makefile_writer.VarsDictData(vars_dict=vars_dict, name=name,
+                                      condition=condition)
+
+
+def generate_dummy_makefile(target_dir):
+  """Create a dummy makefile to demonstrate how it works.
+
+  Use dummy values unrelated to any gyp files. Its output should remain the
+  same unless/until makefile_writer.write_android_mk changes.
+
+  Args:
+      target_dir: directory in which to write the resulting Android.mk
+  """
+  common_vars_dict = generate_dummy_vars_dict(None)
+
+  deviation_params = [('foo', 'COND'), ('bar', None)]
+  deviations = [generate_dummy_vars_dict_data(name, condition)
+                for (name, condition) in deviation_params]
+
+  makefile_writer.write_android_mk(target_dir=target_dir,
+                                   common=common_vars_dict,
+                                   deviations_from_common=deviations)
+
+
+class MakefileWriterTest(unittest.TestCase):
+
+  def test_write_group_empty(self):
+    f = tempfile.TemporaryFile()
+    assert f.tell() == 0
+    for empty in (None, []):
+      for truth in (True, False):
+        makefile_writer.write_group(f, 'name', empty, truth)
+        self.assertEqual(f.tell(), 0)
+    f.close()
+
+  def __compare_files(self, actual_name, expectation_name, msg=None):
+    """Check that two files are identical.
+
+    Assert line by line that the files match.
+
+    Args:
+        actual_name: Full path to the test file.
+        expectation_name: Basename of the expectations file within which
+            to compare. The file is expected to be in
+            platform_tools/android/tests/expectations.
+        msg: Message to pass to assertEqual.
+    Raises:
+        AssertionError: If the files do not match.
+    """
+    with open(actual_name, 'r') as result:
+      with open(os.path.join(EXPECTATIONS_DIR,
+                             expectation_name)) as expectation:
+        for line in result:
+          self.assertEqual(line, expectation.readline(), msg)
+
+  def test_write_group(self):
+    animals = ('dog', 'cat', 'mouse', 'elephant')
+    fd, filename = tempfile.mkstemp()
+    with open(filename, 'w') as f:
+      makefile_writer.write_group(f, 'animals', animals, False)
+    os.close(fd)
+    # Now confirm that it matches expectations
+    self.__compare_files(filename, 'animals.txt')
+
+    with open(filename, 'w') as f:
+      makefile_writer.write_group(f, 'animals_append', animals, True)
+    # Now confirm that it matches expectations
+    self.__compare_files(filename, 'animals_append.txt')
+    os.remove(filename)
+
+  def test_write_local_vars(self):
+    vars_dict = generate_dummy_vars_dict(None)
+
+    # Call variations of write_local_vars.
+    for append in [ True, False ]:
+      for name in [ None, 'arm', 'foo' ]:
+        # Now write to a temporary file.
+        fd, outfile = tempfile.mkstemp()
+        with open(outfile, 'w') as f:
+          makefile_writer.write_local_vars(f, vars_dict, append, name)
+        os.close(fd)
+
+        # Compare to the expected file.
+        filename = 'write_local_vars'
+        if append:
+          filename += '_append'
+        else:
+          filename += '_no_append'
+        if name:
+          filename += '_' + name
+        else:
+          filename += '_no_name'
+        self.__compare_files(outfile, filename)
+
+        # KNOWN_TARGETS is always a part of the input VarsDict, but it should
+        # not be written to the resulting file.
+        # Note that this assumes none of our dummy entries is 'KNOWN_TARGETS'.
+        known_targets_name = 'KNOWN_TARGETS'
+        self.assertEqual(len(vars_dict[known_targets_name]), 1)
+
+        with open(outfile, 'r') as f:
+          self.assertNotIn(known_targets_name, f.read())
+        os.remove(outfile)
+
+  def test_write_android_mk(self):
+    outdir = tempfile.mkdtemp()
+    generate_dummy_makefile(outdir)
+
+    self.__compare_files(os.path.join(outdir, MAKEFILE_NAME), MAKEFILE_NAME,
+                         'If you\'ve modified makefile_writer.py, run ' +
+                         '"makefile_writer_tests.py --rebaseline" ' +
+                         'to rebaseline')
+
+    shutil.rmtree(outdir)
+
+
+def main():
+  loader = unittest.TestLoader()
+  suite = loader.loadTestsFromTestCase(MakefileWriterTest)
+  results = unittest.TextTestRunner(verbosity=2).run(suite)
+  print repr(results)
+  if not results.wasSuccessful():
+    raise Exception('failed one or more unittests')
+
+
+if __name__ == '__main__':
+  parser = argparse.ArgumentParser()
+  parser.add_argument('-r', '--rebaseline',
+                      help='Rebaseline expectation for Android.mk',
+                      action='store_true')
+  args = parser.parse_args()
+
+  if args.rebaseline:
+    generate_dummy_makefile(EXPECTATIONS_DIR)
+  else:
+    main()
+