Refactor CQL handling and fix identifier escaping

Move escape and dequote functions to CqlParsingRuleSet superclass for
better reusability and cleaner inheritance. Fix escape_name() to use
double-quote escaping for CQL identifiers and update tests accordingly.

patch by Jai Bheemsen Dhanwada; reviewed by [Reviewers] for CASSANDRA-20400

pylib/cqlshlib/cql3handling.py

@@ -116,43 +116,6 @@ class Cql3ParsingRuleSet(CqlParsingRuleSet):
         'overlap_inclusion_method'
     )
 
-    @classmethod
-    def escape_value(cls, value):
-        if value is None:
-            return 'NULL'  # this totally won't work
-        if isinstance(value, bool):
-            value = str(value).lower()
-        elif isinstance(value, float):
-            return '%f' % value
-        elif isinstance(value, int):
-            return str(value)
-        return "'%s'" % value.replace("'", "''")
-
-    @classmethod
-    def escape_name(cls, name):
-        if name is None:
-            return 'NULL'
-        return "'%s'" % name.replace("'", "''")
-
-    @staticmethod
-    def dequote_name(name):
-        name = name.strip()
-        if name == '':
-            return name
-        if name[0] == '"' and name[-1] == '"':
-            return name[1:-1].replace('""', '"')
-        else:
-            return name.lower()
-
-    @staticmethod
-    def dequote_value(cqlword):
-        cqlword = cqlword.strip()
-        if cqlword == '':
-            return cqlword
-        if cqlword[0] == "'" and cqlword[-1] == "'":
-            cqlword = cqlword[1:-1].replace("''", "'")
-        return cqlword
-
 
 CqlRuleSet = Cql3ParsingRuleSet()
 

pylib/cqlshlib/cqlhandling.py

@@ -132,6 +132,43 @@ class CqlParsingRuleSet(pylexotron.ParsingRuleSet):
         tokens = self.cql_massage_tokens(tokens)
         return self.parse(startsymbol, tokens, init_bindings={'*SRC*': text})
 
+    @staticmethod
+    def dequote_value(cqlword):
+        cqlword = cqlword.strip()
+        if cqlword == '':
+            return cqlword
+        if cqlword[0] == "'" and cqlword[-1] == "'":
+            cqlword = cqlword[1:-1].replace("''", "'")
+        return cqlword
+
+    @staticmethod
+    def dequote_name(name):
+        name = name.strip()
+        if name == '':
+            return name
+        if name[0] == '"' and name[-1] == '"':
+            return name[1:-1].replace('""', '"')
+        else:
+            return name.lower()
+
+    @staticmethod
+    def escape_value(value):
+        if value is None:
+            return 'NULL'  # this totally won't work
+        if isinstance(value, bool):
+            value = str(value).lower()
+        elif isinstance(value, float):
+            return '%f' % value
+        elif isinstance(value, int):
+            return str(value)
+        return "'%s'" % value.replace("'", "''")
+
+    @staticmethod
+    def escape_name(name):
+        if name is None:
+            return 'NULL'
+        return '"%s"' % name.replace('"', '""')
+
     def cql_whole_parse_tokens(self, toklist, srcstr=None, startsymbol='Start'):
         return self.whole_match(startsymbol, toklist, srcstr=srcstr)
 

pylib/cqlshlib/saferscanner.py

@@ -30,6 +30,7 @@ class SaferScannerBase(re.Scanner):
 
     @classmethod
     def subpat(cls, phrase, flags):
+        # pylint: disable=no-member
         return cls.scrub_sub(re.sre_parse.parse(phrase, flags), flags)
 
     @classmethod
@@ -38,6 +39,7 @@ class SaferScannerBase(re.Scanner):
         seqtypes = (type(()), type([]))
         for op, arg in sub.data:
             if type(arg) in seqtypes:
+                # pylint: disable=no-member
                 arg = [cls.scrub_sub(a, flags) if isinstance(a, re.sre_parse.SubPattern) else a
                        for a in arg]
             if op in (BRANCH, SUBPATTERN):
@@ -49,6 +51,7 @@ class SaferScannerBase(re.Scanner):
             raise ValueError("Named captures not allowed in SaferScanner lexicon")
         if sub.pattern.flags ^ flags:
             raise ValueError("RE flag setting not allowed in SaferScanner lexicon (%s)" % (bin(sub.pattern.flags),))
+        # pylint: disable=no-member
         return re.sre_parse.SubPattern(sub.pattern, scrubbedsub)
 
 
@@ -57,6 +60,7 @@ class Py36SaferScanner(SaferScannerBase):
     def __init__(self, lexicon, flags=0):
         self.lexicon = lexicon
         p = []
+        # pylint: disable=no-member
         s = re.sre_parse.Pattern()
         s.flags = flags
         for phrase, action in lexicon:
@@ -73,6 +77,7 @@ class Py38SaferScanner(SaferScannerBase):
     def __init__(self, lexicon, flags=0):
         self.lexicon = lexicon
         p = []
+        # pylint: disable=no-member
         s = re.sre_parse.State()
         s.flags = flags
         for phrase, action in lexicon:
@@ -89,6 +94,7 @@ class Py311SaferScanner(SaferScannerBase):
     def __init__(self, lexicon, flags=0):
         self.lexicon = lexicon
         p = []
+        # pylint: disable=no-member
         s = re._parser.State()
         s.flags = flags
         for phrase, action in lexicon:

pylib/cqlshlib/test/test_rule_set_utils.py

@@ -0,0 +1,44 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you 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.
+
+from .basecase import BaseTestCase
+from cqlshlib.cql3handling import CqlRuleSet
+
+
+class TestRuleSetUtils(BaseTestCase):
+    def test_dequote_value(self):
+        self.assertEqual(CqlRuleSet.dequote_value("'test'"), "test")
+        self.assertEqual(CqlRuleSet.dequote_value("'test''val'"), "test'val")
+        self.assertEqual(CqlRuleSet.dequote_value("unquoted"), "unquoted")
+        self.assertEqual(CqlRuleSet.dequote_value(""), "")
+
+    def test_dequote_name(self):
+        self.assertEqual(CqlRuleSet.dequote_name('"TestName"'), "TestName")
+        self.assertEqual(CqlRuleSet.dequote_name('"Test""Name"'), 'Test"Name')
+        self.assertEqual(CqlRuleSet.dequote_name("LowercaseName"), "lowercasename")
+        self.assertEqual(CqlRuleSet.dequote_name(""), "")
+
+    def test_escape_value(self):
+        self.assertEqual(CqlRuleSet.escape_value("val'with'quote"), "'val''with''quote'")
+        self.assertEqual(CqlRuleSet.escape_value(True), "'true'")
+        self.assertEqual(CqlRuleSet.escape_value(123), "123")
+        self.assertEqual(CqlRuleSet.escape_value(1.23), "1.230000")
+        self.assertEqual(CqlRuleSet.escape_value(None), "NULL")
+
+    def test_escape_name(self):
+        self.assertEqual(CqlRuleSet.escape_name('name"with"quote'), '"name""with""quote"')
+        self.assertEqual(CqlRuleSet.dequote_name(CqlRuleSet.escape_name('name"with"quote')), 'name"with"quote')
+        self.assertEqual(CqlRuleSet.escape_name(None), "NULL")