Respond to maintainer feedback

tests/rules/test_quoted_strings.py

@@ -14,7 +14,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 from tests.common import RuleTestCase
-from yaml.reader import ReaderError as yaml_reader_ReaderError
+import yaml.reader
 
 from yamllint import config
 
@@ -479,24 +479,20 @@ def test_only_when_needed_extras(self):
     def test_only_when_needed_special_characters(self):
         conf = 'quoted-strings: {required: only-when-needed}\n'
         self.check('---\n'
-                   # double-quoted escaped special chars: ok
                    'k1: "\\u001b"\n',
                    conf)
-
-    def test_only_when_needed_special_characters_exceptions(self):
-        conf = 'quoted-strings: {required: only-when-needed}\n'
-        yamltext1 = ('---\n'
-                     # double-quoted unescaped special chars: yuck"
-                     'k1: "\u001b"\n')
-        yamltext2 = ('---\n'
-                     # single-quoted unescaped special chars: yuck"
-                     "k1: '\u001b'\n")
-        yamltext3 = ('---\n'
-                     # unquoted unescaped special chars: yuck"
-                     'k1: \u001b\n')
-        self.assertRaises(yaml_reader_ReaderError, self.check, yamltext1, conf)
-        self.assertRaises(yaml_reader_ReaderError, self.check, yamltext2, conf)
-        self.assertRaises(yaml_reader_ReaderError, self.check, yamltext3, conf)
+        self.assertRaises(yaml.reader.ReaderError, self.check,
+                          '---\n'
+                          'k1: "\u001b"\n',
+                          conf)
+        self.assertRaises(yaml.reader.ReaderError, self.check,
+                          '---\n'
+                          "k1: '\u001b'\n",
+                          conf)
+        self.assertRaises(yaml.reader.ReaderError, self.check,
+                          '---\n'
+                          'k1: \u001b\n',
+                          conf)
 
     def test_octal_values(self):
         conf = 'quoted-strings: {required: true}\n'

yamllint/rules/quoted_strings.py

@@ -209,16 +209,15 @@ def _quotes_are_needed(string, style, is_inside_a_flow):
     if is_inside_a_flow and set(string) & {',', '[', ']', '{', '}'}:
         return True
 
-    try:
-        loader = yaml.BaseLoader('key: ' + string)
-    except yaml.reader.ReaderError as e:
-        if e.reason == "special characters are not allowed" and style == '"':
+    if style == '"':
+        try:
+            yaml.reader.Reader('').check_printable('key: ' + string)
+        except yaml.reader.ReaderError:
             # Special characters in a double-quoted string
-            # are assumed to be backslash-escaped
+            # are assumed to have been backslash-escaped
             return True
-        else:
-            raise
 
+    loader = yaml.BaseLoader('key: ' + string)
     # Remove the 5 first tokens corresponding to 'key: ' (StreamStartToken,
     # BlockMappingStartToken, KeyToken, ScalarToken(value=key), ValueToken)
     for _ in range(5):