Refactor infra git libs and testing.

infra/libs/types/__init__.py

Index: infra/libs/types/__init__.py
diff --git a/infra/libs/types/__init__.py b/infra/libs/types/__init__.py
new file mode 100644
index 0000000000000000000000000000000000000000..0d60da620f12185bed2aa89acb63103b7110560a
--- /dev/null
+++ b/infra/libs/types/__init__.py
@@ -0,0 +1,7 @@
+# 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.
+
+from infra.libs.types.types import freeze

[Vadim Sh., 2014/06/30 17:24:12]

I don't understand how package __init__ works :( When is it executed? During its
execution, is the package already "defined"? And if so, looks like package
submodules should not rely on side effects of __init__.py...

[iannucci, 2014/06/30 23:03:03]

The process, IIUC, is something like:
  add empty module to sys.modules
  set default __path__ on empty module
  run code in __init__ with module as globals()
  If you see an import during execution
    find module in sys.modules
    use __path__ to understand how to find sub modules

So, if you don't need to tweak __path__, then imports just work as intended. If
you do some imports, tweak __path__ and then do other imports, the second set of
imports will pick up the change to __path__ but the first set will not.

You can even import the same module during the import of that module. As long as
you don't access a member of that module which hasn't been assigned yet, it's
fine.

I just verified this with:
  # pkg/__int__.py
    import sys
    print 'in pkg', id(sys.modules[__name__])
    import pkg.foo
    print 'in pkg', pkg.foo, id(pkg.foo)
 
  # pkg/foo/__init__.py
    import sys
    print 'in foo', id(sys.modules[__name__])
    import pkg
    print 'in foo', pkg, id(pkg)

  # run.py
  import pkg

running run.py gives
  in pkg 4554776536
  in foo 4554789000
  in foo <module 'pkg' from '/.../pkg/__init__.pyc'> 4554776536
  in pkg <module 'pkg.foo' from '/.../pkg/foo/__init__.pyc'> 4554789000

+from infra.libs.types.types import thaw
+from infra.libs.types.types import FrozenDict