Fixed CF creation to trap imports of non-existent values

moto/cloudformation/exceptions.py

@@ -33,6 +33,18 @@ class MissingParameterError(BadRequest):
         )
 
 
+class ExportNotFound(BadRequest):
+    """Exception to raise if a template tries to import a non-existent export"""
+
+    def __init__(self, export_name):
+        template = Template(ERROR_RESPONSE)
+        super(ExportNotFound, self).__init__()
+        self.description = template.render(
+            code='ExportNotFound',
+            message="No export named {0} found.".format(export_name)
+        )
+
+
 ERROR_RESPONSE = """<ErrorResponse xmlns="http://cloudformation.amazonaws.com/doc/2010-05-15/">
   <Error>
     <Type>Sender</Type>

moto/cloudformation/models.py

@@ -38,7 +38,7 @@ class FakeStack(BaseModel):
                                   resource_status_reason="User Initiated")
 
         self.description = self.template_dict.get('Description')
-        self.cross_stack_resources = cross_stack_resources or []
+        self.cross_stack_resources = cross_stack_resources or {}
         self.resource_map = self._create_resource_map()
         self.output_map = self._create_output_map()
         self._add_stack_event("CREATE_COMPLETE")

moto/cloudformation/parsing.py

@@ -28,7 +28,7 @@ from moto.s3 import models as s3_models
 from moto.sns import models as sns_models
 from moto.sqs import models as sqs_models
 from .utils import random_suffix
-from .exceptions import MissingParameterError, UnformattedGetAttTemplateException, ValidationError
+from .exceptions import ExportNotFound, MissingParameterError, UnformattedGetAttTemplateException, ValidationError
 from boto.cloudformation.stack import Output
 
 MODEL_MAP = {
@@ -206,6 +206,8 @@ def clean_json(resource_json, resources_map):
             values = [x.value for x in resources_map.cross_stack_resources.values() if x.name == cleaned_val]
             if any(values):
                 return values[0]
+            else:
+                raise ExportNotFound(cleaned_val)
 
         if 'Fn::GetAZs' in resource_json:
             region = resource_json.get('Fn::GetAZs') or DEFAULT_REGION