From 412b5350ce3c16c55c6625e772f560aba351364b Mon Sep 17 00:00:00 2001
From: Paulus Schoutsen <paulus@paulusschoutsen.nl>
Date: Fri, 30 Sep 2016 23:26:15 -0700
Subject: [PATCH] Service config calls will no longer mutate original config
 (#3628)

---
 homeassistant/helpers/service.py  | 26 +++++++++++---------------
 homeassistant/helpers/template.py |  6 ++++++
 tests/helpers/test_service.py     | 29 +++++++++++++++++------------
 3 files changed, 34 insertions(+), 27 deletions(-)

diff --git a/homeassistant/helpers/service.py b/homeassistant/helpers/service.py
index 092d5983308..665e22404c6 100644
--- a/homeassistant/helpers/service.py
+++ b/homeassistant/helpers/service.py
@@ -62,22 +62,18 @@ def call_from_config(hass, config, blocking=False, variables=None,
     domain, service_name = domain_service.split('.', 1)
     service_data = dict(config.get(CONF_SERVICE_DATA, {}))
 
-    def _data_template_creator(value):
-        """Recursive template creator helper function."""
-        if isinstance(value, list):
-            for idx, element in enumerate(value):
-                value[idx] = _data_template_creator(element)
-            return value
-        if isinstance(value, dict):
-            for key, element in value.items():
-                value[key] = _data_template_creator(element)
-            return value
-        value.hass = hass
-        return value.render(variables)
-
     if CONF_SERVICE_DATA_TEMPLATE in config:
-        for key, value in config[CONF_SERVICE_DATA_TEMPLATE].items():
-            service_data[key] = _data_template_creator(value)
+        def _data_template_creator(value):
+            """Recursive template creator helper function."""
+            if isinstance(value, list):
+                return [_data_template_creator(item) for item in value]
+            elif isinstance(value, dict):
+                return {key: _data_template_creator(item)
+                        for key, item in value.items()}
+            value.hass = hass
+            return value.render(variables)
+        service_data.update(_data_template_creator(
+            config[CONF_SERVICE_DATA_TEMPLATE]))
 
     if CONF_SERVICE_ENTITY_ID in config:
         service_data[ATTR_ENTITY_ID] = config[CONF_SERVICE_ENTITY_ID]
diff --git a/homeassistant/helpers/template.py b/homeassistant/helpers/template.py
index 6193d7f9ab8..03029c369e6 100644
--- a/homeassistant/helpers/template.py
+++ b/homeassistant/helpers/template.py
@@ -159,6 +159,12 @@ class Template(object):
 
         return self._compiled
 
+    def __eq__(self, other):
+        """Compare template with another."""
+        return (self.__class__ == other.__class__ and
+                self.template == other.template and
+                self.hass == other.hass)
+
 
 class AllStates(object):
     """Class to expose all HA states as attributes."""
diff --git a/tests/helpers/test_service.py b/tests/helpers/test_service.py
index d9fe3ff9c15..38af2178340 100644
--- a/tests/helpers/test_service.py
+++ b/tests/helpers/test_service.py
@@ -1,4 +1,5 @@
 """Test service helpers."""
+from copy import deepcopy
 import unittest
 from unittest.mock import patch
 
@@ -6,7 +7,8 @@ from unittest.mock import patch
 import homeassistant.components  # noqa
 from homeassistant import core as ha, loader
 from homeassistant.const import STATE_ON, STATE_OFF, ATTR_ENTITY_ID
-from homeassistant.helpers import service
+from homeassistant.helpers import service, template
+import homeassistant.helpers.config_validation as cv
 
 from tests.common import get_test_home_assistant, mock_service
 
@@ -97,22 +99,25 @@ class TestServiceHelpers(unittest.TestCase):
 
     def test_not_mutate_input(self):
         """Test for immutable input."""
-        orig = {
+        config = cv.SERVICE_SCHEMA({
             'service': 'test_domain.test_service',
             'entity_id': 'hello.world, sensor.beer',
             'data': {
                 'hello': 1,
             },
-        }
-        service.call_from_config(self.hass, orig)
-        self.hass.block_till_done()
-        self.assertEqual({
-            'service': 'test_domain.test_service',
-            'entity_id': 'hello.world, sensor.beer',
-            'data': {
-                'hello': 1,
-            },
-        }, orig)
+            'data_template': {
+                'nested': {
+                    'value': '{{ 1 + 1 }}'
+                }
+            }
+        })
+        orig = deepcopy(config)
+
+        # Only change after call is each template getting hass attached
+        template.attach(self.hass, orig)
+
+        service.call_from_config(self.hass, config, validate_config=False)
+        assert orig == config
 
     @patch('homeassistant.helpers.service._LOGGER.error')
     def test_fail_silently_if_no_service(self, mock_log):