Adding support to conditionally replace a value

Bug: 231691643
Test: presubmit
Change-Id: I786ab152a94126ebc8a9d7dea0bb68e07d789a0b

scripts/Android.bp

@@ -84,6 +84,16 @@ python_binary_host {
     ],
 }
 
+python_test_host {
+    name: "jsonmodify_test",
+    main: "jsonmodify_test.py",
+    srcs: [
+        "jsonmodify_test.py",
+        "jsonmodify.py",
+    ],
+    test_suites: ["general-tests"],
+}
+
 python_binary_host {
     name: "test_config_fixer",
     main: "test_config_fixer.py",

scripts/jsonmodify.py

@@ -59,6 +59,13 @@ class Replace(str):
       cur[key] = val
 
 
+class ReplaceIfEqual(str):
+  def apply(self, obj, old_val, new_val):
+    cur, key = follow_path(obj, self)
+    if cur and cur[key] == int(old_val):
+      cur[key] = new_val
+
+
 class Remove(str):
   def apply(self, obj):
     cur, key = follow_path(obj, self)
@@ -91,6 +98,11 @@ def main():
                       help='replace value of the key specified by path. If path doesn\'t exist, no op.',
                       metavar=('path', 'value'),
                       nargs=2, dest='patch', action='append')
+  parser.add_argument("-se", "--replace-if-equal", type=ReplaceIfEqual,
+                      help='replace value of the key specified by path to new_value if it\'s equal to old_value.' +
+                      'If path doesn\'t exist or the value is not equal to old_value, no op.',
+                      metavar=('path', 'old_value', 'new_value'),
+                      nargs=3, dest='patch', action='append')
   parser.add_argument("-r", "--remove", type=Remove,
                       help='remove the key specified by path. If path doesn\'t exist, no op.',
                       metavar='path',

scripts/jsonmodify_test.py

@@ -0,0 +1,75 @@
+#!/usr/bin/env python
+#
+# Copyright (C) 2022 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+"""Tests for jsonmodify."""
+
+import json
+import jsonmodify
+import unittest
+
+
+class JsonmodifyTest(unittest.TestCase):
+
+  def test_set_value(self):
+    obj = json.loads('{"field1": 111}')
+    field1 = jsonmodify.SetValue("field1")
+    field1.apply(obj, 222)
+    field2 = jsonmodify.SetValue("field2")
+    field2.apply(obj, 333)
+    expected = json.loads('{"field1": 222, "field2": 333}')
+    self.assertEqual(obj, expected)
+
+  def test_replace(self):
+    obj = json.loads('{"field1": 111}')
+    field1 = jsonmodify.Replace("field1")
+    field1.apply(obj, 222)
+    field2 = jsonmodify.Replace("field2")
+    field2.apply(obj, 333)
+    expected = json.loads('{"field1": 222}')
+    self.assertEqual(obj, expected)
+
+  def test_replace_if_equal(self):
+    obj = json.loads('{"field1": 111, "field2": 222}')
+    field1 = jsonmodify.ReplaceIfEqual("field1")
+    field1.apply(obj, 111, 333)
+    field2 = jsonmodify.ReplaceIfEqual("field2")
+    field2.apply(obj, 444, 555)
+    field3 = jsonmodify.ReplaceIfEqual("field3")
+    field3.apply(obj, 666, 777)
+    expected = json.loads('{"field1": 333, "field2": 222}')
+    self.assertEqual(obj, expected)
+
+  def test_remove(self):
+    obj = json.loads('{"field1": 111, "field2": 222}')
+    field2 = jsonmodify.Remove("field2")
+    field2.apply(obj)
+    field3 = jsonmodify.Remove("field3")
+    field3.apply(obj)
+    expected = json.loads('{"field1": 111}')
+    self.assertEqual(obj, expected)
+
+  def test_append_list(self):
+    obj = json.loads('{"field1": [111]}')
+    field1 = jsonmodify.AppendList("field1")
+    field1.apply(obj, 222, 333)
+    field2 = jsonmodify.AppendList("field2")
+    field2.apply(obj, 444, 555, 666)
+    expected = json.loads('{"field1": [111, 222, 333], "field2": [444, 555, 666]}')
+    self.assertEqual(obj, expected)
+
+
+if __name__ == '__main__':
+    unittest.main(verbosity=2)