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diff --git a/third_party/python/yamllint/yamllint/rules/empty_values.py b/third_party/python/yamllint/yamllint/rules/empty_values.py
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+++ b/third_party/python/yamllint/yamllint/rules/empty_values.py
@@ -0,0 +1,96 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2017 Greg Dubicki
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+"""
+Use this rule to prevent nodes with empty content, that implicitly result in
+``null`` values.
+
+.. rubric:: Options
+
+* Use ``forbid-in-block-mappings`` to prevent empty values in block mappings.
+* Use ``forbid-in-flow-mappings`` to prevent empty values in flow mappings.
+
+.. rubric:: Examples
+
+#. With ``empty-values: {forbid-in-block-mappings: true}``
+
+   the following code snippets would **PASS**:
+   ::
+
+    some-mapping:
+      sub-element: correctly indented
+
+   ::
+
+    explicitly-null: null
+
+   the following code snippets would **FAIL**:
+   ::
+
+    some-mapping:
+    sub-element: incorrectly indented
+
+   ::
+
+    implicitly-null:
+
+#. With ``empty-values: {forbid-in-flow-mappings: true}``
+
+   the following code snippet would **PASS**:
+   ::
+
+    {prop: null}
+    {a: 1, b: 2, c: 3}
+
+   the following code snippets would **FAIL**:
+   ::
+
+    {prop: }
+
+   ::
+
+    {a: 1, b:, c: 3}
+
+"""
+
+import yaml
+
+from yamllint.linter import LintProblem
+
+
+ID = 'empty-values'
+TYPE = 'token'
+CONF = {'forbid-in-block-mappings': bool,
+        'forbid-in-flow-mappings': bool}
+DEFAULT = {'forbid-in-block-mappings': True,
+           'forbid-in-flow-mappings': True}
+
+
+def check(conf, token, prev, next, nextnext, context):
+
+    if conf['forbid-in-block-mappings']:
+        if isinstance(token, yaml.ValueToken) and isinstance(next, (
+                yaml.KeyToken, yaml.BlockEndToken)):
+            yield LintProblem(token.start_mark.line + 1,
+                              token.end_mark.column + 1,
+                              'empty value in block mapping')
+
+    if conf['forbid-in-flow-mappings']:
+        if isinstance(token, yaml.ValueToken) and isinstance(next, (
+                yaml.FlowEntryToken, yaml.FlowMappingEndToken)):
+            yield LintProblem(token.start_mark.line + 1,
+                              token.end_mark.column + 1,
+                              'empty value in flow mapping')