Redefine/reimplement CDIST_ORDER_DEPENDENCY

CDIST_ORDER_DEPENDENCY now defines type order dependency context.
cdist (emulator) maintains global state variables, as files,
order_dep_state and typeorder_dep, and per object state variable,
as file, typeorder_dep.

If order_dep_state exists then this defines that order dependency is
turned on.
If order_dep_state does not exist then order dependency is turned off.

If order dependency is on then objects created after it is turned on are
recorded into:
    * global typeorder_dep, in case of init manifest
    * object's typeorder_dep, in case of type's manifest.

If order dependency is on then requirement is injected, where object
created before current, is read from:
    * global typeorder_dep, in case of init manifest
    * object's typeorder_dep, in case of type's manifest.

Every time order dependency is turned off, typeorder_dep files are
removed, which means that type order list is cleared, context is
cleaned.

In the end cdist cleans after itself, i.e. mentioned files are removed.

When running type manifest is finished typeorder_dep file is removed.
When running config finishes global typeorder_dep and order_dep_state
files are removed.

Global type order recording is untouched.
Furthermore, for completeness, type order is now recorded for each object
too.

cdist/test/emulator/__init__.py

@@ -24,8 +24,6 @@
 import io
 import os
 import shutil
-import string
-import filecmp
 import random
 import logging
 
@@ -34,7 +32,6 @@ from cdist import test
 from cdist.exec import local
 from cdist import emulator
 from cdist import core
-from cdist import config
 
 import os.path as op
 my_dir = op.abspath(op.dirname(__file__))
@@ -115,7 +112,7 @@ class EmulatorTestCase(test.CdistTestCase):
     def test_requirement_pattern(self):
         argv = ['__file', '/tmp/foobar']
         self.env['require'] = '__file/etc/*'
-        emu = emulator.Emulator(argv, env=self.env)
+        emulator.Emulator(argv, env=self.env)
         # if we get here all is fine
 
     def test_loglevel(self):
@@ -172,6 +169,44 @@ class EmulatorTestCase(test.CdistTestCase):
         self.assertEqual(list(file_object.requirements), ['__planet/mars'])
         # if we get here all is fine
 
+    def test_order_dependency_context(self):
+        test_seq = ('A', True, 'B', 'C', 'D', False, 'E', 'F', True, 'G',
+                    'H', False, 'I', )
+        expected_requirements = {
+            'C': set(('__planet/B', )),
+            'D': set(('__planet/C', )),
+            'H': set(('__planet/G', )),
+        }
+        # Ensure env var is not in env
+        if 'CDIST_ORDER_DEPENDENCY' in self.env:
+            del self.env['CDIST_ORDER_DEPENDENCY']
+
+        for x in test_seq:
+            if isinstance(x, str):
+                # Clear because of order dep injection
+                # In real world, this is not shared over instances
+                if 'require' in self.env:
+                    del self.env['require']
+                argv = ['__planet', x]
+                emu = emulator.Emulator(argv, env=self.env)
+                emu.run()
+            elif isinstance(x, bool):
+                if x:
+                    self.env['CDIST_ORDER_DEPENDENCY'] = 'on'
+                elif 'CDIST_ORDER_DEPENDENCY' in self.env:
+                    del self.env['CDIST_ORDER_DEPENDENCY']
+        cdist_type = core.CdistType(self.local.type_path, '__planet')
+        for x in test_seq:
+            if isinstance(x, str):
+                obj = core.CdistObject(cdist_type, self.local.object_path,
+                                       self.local.object_marker_name, x)
+                reqs = set(obj.requirements)
+                if x in expected_requirements:
+                    self.assertEqual(reqs, expected_requirements[x])
+                else:
+                    self.assertTrue(len(reqs) == 0)
+        # if we get here all is fine
+
 
 class EmulatorConflictingRequirementsTestCase(test.CdistTestCase):