Add simple depends_on API.

recipe_engine/recipe_test_api.py

Index: recipe_engine/recipe_test_api.py
diff --git a/recipe_engine/recipe_test_api.py b/recipe_engine/recipe_test_api.py
index bb1da1cf0b66c6c54c7829a388d741a477ee3f9d..99b67053b6bebf4b3821f8aed434b93bd687ee94 100644
--- a/recipe_engine/recipe_test_api.py
+++ b/recipe_engine/recipe_test_api.py
@@ -5,6 +5,7 @@
 import collections
 
 from .util import ModuleInjectionSite, static_call, static_wraps
+from .types import freeze
 
 def combineify(name, dest, a, b):
   """
@@ -159,6 +160,7 @@ class TestData(BaseTestData):
     self.properties = {}  # key -> val
     self.mod_data = collections.defaultdict(ModuleTestData)
     self.step_data = collections.defaultdict(StepTestData)
+    self.depend_on_data = {}

[luqui, 2015/11/16 20:48:00]

This is a little worrisome to me.  Why isn't depend_on just a special kind of
step?

[martiniss, 2015/11/18 01:00:00]

Because it's not a step? I have to mock the output based on the key of (name,
properties). It seems strange to stick that into a string as the step name. 

     self.expected_exception = None
 
   def __add__(self, other):
@@ -170,6 +172,7 @@ class TestData(BaseTestData):
 
     combineify('mod_data', ret, self, other)
     combineify('step_data', ret, self, other)
+    combineify('depend_on_data', ret, self, other)
     ret.expected_exception = self.expected_exception
     if other.expected_exception:
       ret.expected_exception = other.expected_exception
@@ -198,6 +201,12 @@ class TestData(BaseTestData):
     name = exception.__class__.__name__
     return not (self.enabled and name == self.expected_exception)
 
+  def depend_on(self, recipe, properties, result):
+    tup = freeze((recipe, properties))
+    assert tup not in self.depend_on_data, (
+        'Already gave test data for %s' % recipe)
+    self.depend_on_data[tup] = freeze(result)
+
   def __repr__(self):
     return "TestData(%r)" % ({
       'name': self.name,
@@ -205,6 +214,7 @@ class TestData(BaseTestData):
       'mod_data': dict(self.mod_data.iteritems()),
       'step_data': dict(self.step_data.iteritems()),
       'expected_exception': self.expected_exception,
+      'depend_on_data': self.depend_on_data

[luqui, 2015/11/16 20:48:00]

ubernit: ultimate comma

[martiniss, 2015/11/18 01:00:00]

Done.

     },)
 
 
@@ -462,3 +472,8 @@ class RecipeTestApi(object):
     ret = TestData(None)
     ret.expect_exception(exc_type)
     return ret
+
+  def depend_on(self, recipe, properties, result):
+    ret = TestData()
+    ret.depend_on(recipe, properties, result)
+    return ret