Added PRESUBMIT.py for binary_size tools.

tools/binary_size/explain_binary_size_delta_unittest.py

Index: tools/binary_size/explain_binary_size_delta_unittest.py
diff --git a/tools/binary_size/explain_binary_size_delta_unittest.py b/tools/binary_size/explain_binary_size_delta_unittest.py
new file mode 100755
index 0000000000000000000000000000000000000000..58da34eac97e48812ac16c731f3a5afc3ef80652
--- /dev/null
+++ b/tools/binary_size/explain_binary_size_delta_unittest.py
@@ -0,0 +1,210 @@
+#!/usr/bin/env python
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Check that explain_binary_size_delta seems to work."""
+
+import cStringIO
+import sys

[Primiano Tucci (use gerrit), 2014/05/22 09:30:38]

you can import unittest and use it, as all the other unittests do.
THis will avoid you handling the hand crafted diff magic (see below).

+
+import explain_binary_size_delta
+
+
+def TestCompare():

[Primiano Tucci (use gerrit), 2014/05/22 09:30:38]

This should be
class TestCompare(unittest.TestCase):
  def runTest(self):

+  # List entries have form: symbol_name, symbol_type, symbol_size, file_path
+  symbol_list1 = (
+    # File with one symbol, left as-is.
+    ( 'unchanged', 't', 1000, '/file_unchanged' ),
+    # File with one symbol, changed.
+    ( 'changed', 't', 1000, '/file_all_changed' ),
+    # File with one symbol, deleted.
+    ( 'removed', 't', 1000, '/file_all_deleted' ),
+    # File with two symbols, one unchanged, one changed, same bucket
+    ( 'unchanged', 't', 1000, '/file_pair_unchanged_changed' ),
+    ( 'changed', 't', 1000, '/file_pair_unchanged_changed' ),
+    # File with two symbols, one unchanged, one deleted, same bucket
+    ( 'unchanged', 't', 1000, '/file_pair_unchanged_removed' ),
+    ( 'removed', 't', 1000, '/file_pair_unchanged_removed' ),
+    # File with two symbols, one unchanged, one added, same bucket
+    ( 'unchanged', 't', 1000, '/file_pair_unchanged_added' ),
+    # File with two symbols, one unchanged, one changed, different bucket
+    ( 'unchanged', 't', 1000, '/file_pair_unchanged_diffbuck_changed' ),
+    ( 'changed', '@', 1000, '/file_pair_unchanged_diffbuck_changed' ),
+    # File with two symbols, one unchanged, one deleted, different bucket
+    ( 'unchanged', 't', 1000, '/file_pair_unchanged_diffbuck_removed' ),
+    ( 'removed', '@', 1000, '/file_pair_unchanged_diffbuck_removed' ),
+    # File with two symbols, one unchanged, one added, different bucket
+    ( 'unchanged', 't', 1000, '/file_pair_unchanged_diffbuck_added' ),
+    # File with four symbols, one added, one removed, one changed, one unchanged
+    ( 'size_changed', 't', 1000, '/file_tetra' ),
+    ( 'removed', 't', 1000, '/file_tetra' ),
+    ( 'unchanged', 't', 1000, '/file_tetra' ),
+  )
+
+  symbol_list2 = (
+    # File with one symbol, left as-is.
+    ( 'unchanged', 't', 1000, '/file_unchanged' ),
+    # File with one symbol, changed.
+    ( 'changed', 't', 2000, '/file_all_changed' ),
+    # File with two symbols, one unchanged, one changed, same bucket
+    ( 'unchanged', 't', 1000, '/file_pair_unchanged_changed' ),
+    ( 'changed', 't', 2000, '/file_pair_unchanged_changed' ),
+    # File with two symbols, one unchanged, one deleted, same bucket
+    ( 'unchanged', 't', 1000, '/file_pair_unchanged_removed' ),
+    # File with two symbols, one unchanged, one added, same bucket
+    ( 'unchanged', 't', 1000, '/file_pair_unchanged_added' ),
+    ( 'added', 't', 1000, '/file_pair_unchanged_added' ),
+    # File with two symbols, one unchanged, one changed, different bucket
+    ( 'unchanged', 't', 1000, '/file_pair_unchanged_diffbuck_changed' ),
+    ( 'changed', '@', 2000, '/file_pair_unchanged_diffbuck_changed' ),
+    # File with two symbols, one unchanged, one deleted, different bucket
+    ( 'unchanged', 't', 1000, '/file_pair_unchanged_diffbuck_removed' ),
+    # File with two symbols, one unchanged, one added, different bucket
+    ( 'unchanged', 't', 1000, '/file_pair_unchanged_diffbuck_added' ),
+    ( 'added', '@', 1000, '/file_pair_unchanged_diffbuck_added' ),
+    # File with four symbols, one added, one removed, one changed, one unchanged
+    ( 'size_changed', 't', 2000, '/file_tetra' ),
+    ( 'unchanged', 't', 1000, '/file_tetra' ),
+    ( 'added', 't', 1000, '/file_tetra' ),
+    # New file with one symbol added
+    ( 'added', 't', 1000, '/file_new' ),
+  )
+
+  # Here we go
+  (added, removed, changed, unchanged) = \
+      explain_binary_size_delta.Compare(symbol_list1, symbol_list2)
+
+  # File with one symbol, left as-is.
+  assert ('/file_unchanged', 't', 'unchanged', 1000, 1000) in unchanged

[Primiano Tucci (use gerrit), 2014/05/22 09:30:38]

When you switch to python unittests, you could take advantage here of
self.assertIn (is just more verbose and more explicative in the cases the
assertion fails).
Don't feel personally strong against just assert, though, so do as you prefer.

+  # File with one symbol, changed.
+  assert ('/file_all_changed', 't', 'changed', 1000, 2000) in changed
+  # File with one symbol, deleted.
+  assert ('/file_all_deleted', 't', 'removed', 1000, None) in removed
+  # New file with one symbol added
+  assert ('/file_new', 't', 'added', None, 1000) in added
+  # File with two symbols, one unchanged, one changed, same bucket
+  assert ('/file_pair_unchanged_changed',
+          't', 'unchanged', 1000, 1000) in unchanged
+  assert ('/file_pair_unchanged_changed',
+          't', 'changed', 1000, 2000) in changed
+  # File with two symbols, one unchanged, one removed, same bucket
+  assert ('/file_pair_unchanged_removed',
+          't', 'unchanged', 1000, 1000) in unchanged
+  assert ('/file_pair_unchanged_removed',
+          't', 'removed', 1000, None) in removed
+  # File with two symbols, one unchanged, one added, same bucket
+  assert ('/file_pair_unchanged_added',
+          't', 'unchanged', 1000, 1000) in unchanged
+  assert ('/file_pair_unchanged_added',
+          't', 'added', None, 1000) in added
+  # File with two symbols, one unchanged, one changed, different bucket
+  assert ('/file_pair_unchanged_diffbuck_changed',
+          't', 'unchanged', 1000, 1000) in unchanged
+  assert ('/file_pair_unchanged_diffbuck_changed',
+          '@', 'changed', 1000, 2000) in changed
+  # File with two symbols, one unchanged, one removed, different bucket
+  assert ('/file_pair_unchanged_diffbuck_removed',
+          't', 'unchanged', 1000, 1000) in unchanged
+  assert ('/file_pair_unchanged_diffbuck_removed',
+          '@', 'removed', 1000, None) in removed
+  # File with two symbols, one unchanged, one added, different bucket
+  assert ('/file_pair_unchanged_diffbuck_added',
+          't', 'unchanged', 1000, 1000) in unchanged
+  assert ('/file_pair_unchanged_diffbuck_added',
+          '@', 'added', None, 1000) in added
+  # File with four symbols, one added, one removed, one changed, one unchanged
+  assert ('/file_tetra', 't', 'size_changed', 1000, 2000) in changed
+  assert ('/file_tetra', 't', 'unchanged', 1000, 1000) in unchanged
+  assert ('/file_tetra', 't', 'added', None, 1000) in added
+  assert ('/file_tetra', 't', 'removed', 1000, None) in removed
+
+  # Now check final stats.
+  orig_stdout = sys.stdout
+  output_collector = cStringIO.StringIO()
+  sys.stdout = output_collector
+  try:
+    explain_binary_size_delta.CrunchStats(added, removed, changed,
+                                          unchanged, True, True)
+  finally:
+    sys.stdout = orig_stdout
+  result = output_collector.getvalue()
+
+  expected_output = """\
+Symbol statistics:
+  4 added, totalling 4000 bytes across 4 sources
+  4 removed, totalling 4000 bytes removed across 4 sources
+  4 changed, resulting in a net change of 4000 bytes \
+(4000 bytes before, 8000 bytes after) across 4 sources
+  8 unchanged, totalling 8000 bytes
+Source stats:
+  11 sources encountered.
+  1 completely new.
+  1 removed completely.
+  8 partially changed.
+  1 completely unchanged.
+Per-source Analysis:
+  Source: /file_all_changed
+    Change: 1000 bytes (gained 1000, lost 0)
+    Changed symbols:
+      changed type=t, delta=1000 bytes (was 1000 bytes, now 2000 bytes)
+  Source: /file_all_deleted
+    Change: -1000 bytes (gained 0, lost 1000)
+    Removed symbols:
+      removed type=t, size=1000 bytes
+  Source: /file_new
+    Change: 1000 bytes (gained 1000, lost 0)
+    New symbols:
+      added type=t, size=1000 bytes
+  Source: /file_pair_unchanged_added
+    Change: 1000 bytes (gained 1000, lost 0)
+    New symbols:
+      added type=t, size=1000 bytes
+  Source: /file_pair_unchanged_changed
+    Change: 1000 bytes (gained 1000, lost 0)
+    Changed symbols:
+      changed type=t, delta=1000 bytes (was 1000 bytes, now 2000 bytes)
+  Source: /file_pair_unchanged_diffbuck_added
+    Change: 1000 bytes (gained 1000, lost 0)
+    New symbols:
+      added type=@, size=1000 bytes
+  Source: /file_pair_unchanged_diffbuck_changed
+    Change: 1000 bytes (gained 1000, lost 0)
+    Changed symbols:
+      changed type=@, delta=1000 bytes (was 1000 bytes, now 2000 bytes)
+  Source: /file_pair_unchanged_diffbuck_removed
+    Change: -1000 bytes (gained 0, lost 1000)
+    Removed symbols:
+      removed type=@, size=1000 bytes
+  Source: /file_pair_unchanged_removed
+    Change: -1000 bytes (gained 0, lost 1000)
+    Removed symbols:
+      removed type=t, size=1000 bytes
+  Source: /file_tetra
+    Change: 1000 bytes (gained 2000, lost 1000)
+    New symbols:
+      added type=t, size=1000 bytes
+    Removed symbols:
+      removed type=t, size=1000 bytes
+    Changed symbols:
+      size_changed type=t, delta=1000 bytes (was 1000 bytes, now 2000 bytes)
+"""
+
+  if result != expected_output:

[Primiano Tucci (use gerrit), 2014/05/22 09:30:38]

Lines 193-198 can be simply rewritten as:
self.assertEqual(result.splitlines(), expected_output.splitlines())

Power of python modules ;-)

+    import difflib
+    differ = difflib.Differ()
+    assert False, "Unexpected output:\n" + \
+        "".join(differ.compare(expected_output.splitlines(1),
+                               result.splitlines(1)))
+
+  print "explain_binary_size_delta_unittest: All tests passed"
+  return 0
+
+
+def main():

[Primiano Tucci (use gerrit), 2014/05/22 09:30:38]

remove this.
Python unittests can already auto-discover test cases.

+  """Main entry point."""
+  return TestCompare()
+
+
+if __name__ == '__main__':
+  sys.exit(main())

[Primiano Tucci (use gerrit), 2014/05/22 09:30:38]

s/sys.exit(main())/unittest.main()/