Drop YAML 1.1 boolean and timestamp resolvers

Fixes #148

README.rst

@@ -41,6 +41,9 @@ See the `jq manual <https://stedolan.github.io/jq/manual/>`_ for more details on
 
 Because YAML treats JSON as a dialect of YAML, you can use yq to convert JSON to YAML: ``yq -y . < in.json > out.yml``.
 
+yq aims to use YAML 1.2 as the language specification, but due to limitations in PyYAML we still parse int and float
+literals according to the YAML 1.1 specification.
+
 Preserving tags and styles using the ``-Y`` (``--yaml-roundtrip``) option
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

test/test.py

@@ -149,13 +149,9 @@ def test_multidocs(self):
 
     def test_datetimes(self):
         self.assertEqual(self.run_yq("- 2016-12-20T22:07:36Z\n", ["."]), "")
-        if yaml.__version__ < '5.3':
-            self.assertEqual(self.run_yq("- 2016-12-20T22:07:36Z\n", ["-y", "."]), "- '2016-12-20T22:07:36'\n")
-        else:
-            self.assertEqual(self.run_yq("- 2016-12-20T22:07:36Z\n", ["-y", "."]), "- '2016-12-20T22:07:36+00:00'\n")
-
+        self.assertEqual(self.run_yq("- 2016-12-20T22:07:36Z\n", ["-y", "."]), "- 2016-12-20T22:07:36Z\n")
         self.assertEqual(self.run_yq("2016-12-20", ["."]), "")
-        self.assertEqual(self.run_yq("2016-12-20", ["-y", "."]), "'2016-12-20'\n")
+        self.assertEqual(self.run_yq("2016-12-20", ["-y", "."]), "2016-12-20\n...\n")
 
     def test_unrecognized_tags(self):
         self.assertEqual(self.run_yq("!!foo bar\n", ["."]), "")
@@ -264,5 +260,9 @@ def test_yaml_type_tags(self):
             "example:\n  Boston Red Sox: null\n  Detroit Tigers: null\n  New York Yankees: null\n"
         )
 
+    def test_yaml_1_2(self):
+        self.assertEqual(self.run_yq("on: 1", ["-y", "."]), "on: 1\n")
+        self.assertEqual(self.run_yq("2022-02-22", ["-y", "."]), "2022-02-22\n...\n")
+
 if __name__ == '__main__':
     unittest.main()

yq/__init__.py

@@ -137,6 +137,20 @@ def exit_handler(arg=None):
 
 def load_yaml_docs(in_stream, out_stream, jq, loader_class, max_expansion_factor, exit_func, prog):
     loader = loader_class(in_stream)
+
+    # PyYAML does not yet support YAML 1.2 (https://github.com/yaml/pyyaml/pull/555).
+    # Use this hack to avoid interpreting yes|Yes|YES|no|No|NO|on|On|ON|off|Off|OFF as boolean values,
+    # and avoid interpreting any values as timestamps.
+    for start_char in list(loader.yaml_implicit_resolvers):
+        if start_char in {"y", "Y", "n", "N", "o", "O"}:
+            for i, matcher in enumerate(loader.yaml_implicit_resolvers[start_char]):
+                if matcher[0] == "tag:yaml.org,2002:bool":
+                    del loader.yaml_implicit_resolvers[start_char][i]
+        if start_char in {"0", "1", "2", "3", "4", "5", "6", "7", "8", "9"}:
+            for i, matcher in enumerate(loader.yaml_implicit_resolvers[start_char]):
+                if matcher[0] == "tag:yaml.org,2002:timestamp":
+                    del loader.yaml_implicit_resolvers[start_char][i]
+
     last_loader_pos = 0
     try:
         while loader.check_node():