1 files changed, 78 insertions, 0 deletions
diff --git a/taskcluster/taskgraph/test/test_util_templates.py b/taskcluster/taskgraph/test/test_util_templates.py
new file mode 100644
index 0000000000..afbdfa2f31
--- /dev/null
+++ b/taskcluster/taskgraph/test/test_util_templates.py
@@ -0,0 +1,78 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from __future__ import absolute_import, print_function, unicode_literals
+
+import unittest
+import mozunit
+from taskgraph.util.templates import merge_to, merge
+
+
+class MergeTest(unittest.TestCase):
+    def test_merge_to_dicts(self):
+        source = {"a": 1, "b": 2}
+        dest = {"b": "20", "c": 30}
+        expected = {
+            "a": 1,  # source only
+            "b": 2,  # source overrides dest
+            "c": 30,  # dest only
+        }
+        self.assertEqual(merge_to(source, dest), expected)
+        self.assertEqual(dest, expected)
+
+    def test_merge_to_lists(self):
+        source = {"x": [3, 4]}
+        dest = {"x": [1, 2]}
+        expected = {"x": [1, 2, 3, 4]}  # dest first
+        self.assertEqual(merge_to(source, dest), expected)
+        self.assertEqual(dest, expected)
+
+    def test_merge_diff_types(self):
+        source = {"x": [1, 2]}
+        dest = {"x": "abc"}
+        expected = {"x": [1, 2]}  # source wins
+        self.assertEqual(merge_to(source, dest), expected)
+        self.assertEqual(dest, expected)
+
+    def test_merge(self):
+        first = {"a": 1, "b": 2, "d": 11}
+        second = {"b": 20, "c": 30}
+        third = {"c": 300, "d": 400}
+        expected = {
+            "a": 1,
+            "b": 20,
+            "c": 300,
+            "d": 400,
+        }
+        self.assertEqual(merge(first, second, third), expected)
+
+        # inputs haven't changed..
+        self.assertEqual(first, {"a": 1, "b": 2, "d": 11})
+        self.assertEqual(second, {"b": 20, "c": 30})
+        self.assertEqual(third, {"c": 300, "d": 400})
+
+    def test_merge_by(self):
+        source = {
+            "x": "abc",
+            "y": {"by-foo": {"quick": "fox", "default": ["a", "b", "c"]}},
+        }
+        dest = {"y": {"by-foo": {"purple": "rain", "default": ["x", "y", "z"]}}}
+        expected = {
+            "x": "abc",
+            "y": {"by-foo": {"quick": "fox", "default": ["a", "b", "c"]}},
+        }  # source wins
+        self.assertEqual(merge_to(source, dest), expected)
+        self.assertEqual(dest, expected)
+
+    def test_merge_multiple_by(self):
+        source = {"x": {"by-foo": {"quick": "fox", "default": ["a", "b", "c"]}}}
+        dest = {"x": {"by-bar": {"purple": "rain", "default": ["x", "y", "z"]}}}
+        expected = {
+            "x": {"by-foo": {"quick": "fox", "default": ["a", "b", "c"]}}
+        }  # source wins
+        self.assertEqual(merge_to(source, dest), expected)
+
+
+if __name__ == "__main__":
+    mozunit.main()