Cleanup dependencies and fix OpenCyphal#94 (OpenCyphal#95)

Upgrade Parsimonious to
`v0.10.0+39b3d71ee827ba6a19a7226fddfe6b6e51535794`; fix
OpenCyphal#92. Compare the bundled
version of Parsimonious against its latest release, v0.10.0:
erikrose/parsimonious@0.10.0...39b3d71

Remove dependency on `six.py`

Fix OpenCyphal#94 and add a new error
class -- `DataTypeCollisionError`; remove
`MultipleDefinitionsUnderSameVersionError`. This does not affect the API
compatibility because the specific error classes are private.

Bump the minor version number.

docs/index.rst

@@ -63,26 +63,3 @@ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
-
-Six
-^^^
-
-Copyright (c) 2010-2020 Benjamin Peterson
-
-Permission is hereby granted, free of charge, to any person obtaining a copy
-of this software and associated documentation files (the "Software"), to deal
-in the Software without restriction, including without limitation the rights
-to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-copies of the Software, and to permit persons to whom the Software is
-furnished to do so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.

docs/pages/installation.rst

@@ -22,6 +22,5 @@ The library is bundled with the following third-party software libraries
 (by virtue of being bundled, they are not listed as dependencies and need not be installed by the user):
 
 * `Parsimonious <https://github.com/erikrose/parsimonious>`_ by Erik Rose, MIT license.
-* `Six <https://github.com/benjaminp/six>`_ by Benjamin Peterson, MIT license; needed for Parsimonious.
 
 Please refer to the projects' homepages for more information, including the legal information on licensing.

pydsdl/__init__.py

@@ -7,7 +7,7 @@
 import sys as _sys
 from pathlib import Path as _Path
 
-__version__ = "1.19.0"
+__version__ = "1.20.0"
 __version_info__ = tuple(map(int, __version__.split(".")[:3]))
 __license__ = "MIT"
 __author__ = "OpenCyphal"

pydsdl/_namespace.py

@@ -20,7 +20,13 @@ class RootNamespaceNameCollisionError(_error.InvalidDefinitionError):
     """
 
 
-class DataTypeNameCollisionError(_error.InvalidDefinitionError):
+class DataTypeCollisionError(_error.InvalidDefinitionError):
+    """
+    Raised when there are conflicting data type definitions.
+    """
+
+
+class DataTypeNameCollisionError(DataTypeCollisionError):
     """
     Raised when there are conflicting data type names.
     """
@@ -39,16 +45,6 @@ class FixedPortIDCollisionError(_error.InvalidDefinitionError):
     """
 
 
-class MultipleDefinitionsUnderSameVersionError(_error.InvalidDefinitionError):
-    """
-    For example::
-
-        Type.1.0.dsdl
-        2800.Type.1.0.dsdl
-        2801.Type.1.0.dsdl
-    """
-
-
 class VersionsOfDifferentKindError(_error.InvalidDefinitionError):
     """
     Definitions that share the same name but are of different kinds.
@@ -166,7 +162,7 @@ def read_namespace(
         lookup_dsdl_definitions += _construct_dsdl_definitions_from_namespace(ld)
 
     # Check for collisions against the lookup definitions also.
-    _ensure_no_name_collisions(target_dsdl_definitions, lookup_dsdl_definitions)
+    _ensure_no_collisions(target_dsdl_definitions, lookup_dsdl_definitions)
 
     _logger.debug("Lookup DSDL definitions are listed below:")
     for x in lookup_dsdl_definitions:
@@ -245,7 +241,7 @@ def handler(line_number: int, text: str) -> None:
     return types
 
 
-def _ensure_no_name_collisions(
+def _ensure_no_collisions(
     target_definitions: List[_dsdl_definition.DSDLDefinition],
     lookup_definitions: List[_dsdl_definition.DSDLDefinition],
 ) -> None:
@@ -275,6 +271,12 @@ def _ensure_no_name_collisions(
                 raise DataTypeNameCollisionError(
                     "This type conflicts with the namespace of %s" % lu.file_path, path=tg.file_path
                 )
+            if (
+                tg_full_name_period == lu_full_name_period
+                and tg.version == lu.version
+                and not tg.file_path.samefile(lu.file_path)
+            ):  # https://github.com/OpenCyphal/pydsdl/issues/94
+                raise DataTypeCollisionError("This type is redefined in %s" % lu.file_path, path=tg.file_path)
 
 
 def _ensure_no_fixed_port_id_collisions(types: List[_serializable.CompositeType]) -> None:
@@ -320,14 +322,9 @@ def _ensure_minor_version_compatibility_pairwise(
     a: _serializable.CompositeType, b: _serializable.CompositeType
 ) -> None:
     assert a is not b
-    assert a.version.major == b.version.major
     assert a.full_name == b.full_name
-
-    # Version collision
-    if a.version.minor == b.version.minor:
-        raise MultipleDefinitionsUnderSameVersionError(
-            "This definition shares its version number with %s" % b.source_file_path, path=a.source_file_path
-        )
+    assert a.version.major == b.version.major
+    assert a.version.minor != b.version.minor  # This is the whole point of this function.
 
     # Must be of the same kind: both messages or both services
     if isinstance(a, _serializable.ServiceType) != isinstance(b, _serializable.ServiceType):

pydsdl/_test.py

@@ -1262,7 +1262,7 @@ def _unittest_parse_namespace_versioning(wrkspc: Workspace) -> None:
         ),
     )
 
-    with raises(_namespace.MultipleDefinitionsUnderSameVersionError):
+    with raises(_namespace.DataTypeCollisionError):
         _namespace.read_namespace((wrkspc.directory / "ns"), [])
 
     wrkspc.drop("ns/Spartans.30.2.dsdl")
@@ -1604,6 +1604,27 @@ def _unittest_parse_namespace_versioning(wrkspc: Workspace) -> None:
     wrkspc.drop("ns/Consistency*")
 
 
+def _unittest_issue94(wrkspc: Workspace) -> None:
+    from pytest import raises
+
+    wrkspc.new("outer_a/ns/Foo.1.0.dsdl", "@sealed")
+    wrkspc.new("outer_b/ns/Foo.1.0.dsdl", "@sealed")  # Conflict!
+    wrkspc.new("outer_a/ns/Bar.1.0.dsdl", "Foo.1.0 fo\n@sealed")  # Which Foo.1.0?
+
+    with raises(_namespace.DataTypeCollisionError):
+        _namespace.read_namespace(
+            wrkspc.directory / "outer_a" / "ns",
+            [wrkspc.directory / "outer_b" / "ns"],
+        )
+
+    wrkspc.drop("outer_b/ns/Foo.1.0.dsdl")  # Clear the conflict.
+    defs = _namespace.read_namespace(
+        wrkspc.directory / "outer_a" / "ns",
+        [wrkspc.directory / "outer_b" / "ns"],
+    )
+    assert len(defs) == 2
+
+
 def _unittest_parse_namespace_faults() -> None:
     from pytest import raises
 

pydsdl/third_party/parsimonious/exceptions.py

@@ -1,10 +1,14 @@
-from six import text_type, python_2_unicode_compatible
+from textwrap import dedent
 
 from parsimonious.utils import StrAndRepr
 
 
-@python_2_unicode_compatible
-class ParseError(StrAndRepr, Exception):
+class ParsimoniousError(Exception):
+    """A base exception class to allow library users to catch any Parsimonious error."""
+    pass
+
+
+class ParseError(StrAndRepr, ParsimoniousError):
     """A call to ``Expression.parse()`` or ``match()`` didn't match."""
 
     def __init__(self, text, pos=-1, expr=None):
@@ -16,9 +20,9 @@ def __init__(self, text, pos=-1, expr=None):
         self.expr = expr
 
     def __str__(self):
-        rule_name = ((u"'%s'" % self.expr.name) if self.expr.name else
-                     text_type(self.expr))
-        return u"Rule %s didn't match at '%s' (line %s, column %s)." % (
+        rule_name = (("'%s'" % self.expr.name) if self.expr.name else
+                     str(self.expr))
+        return "Rule %s didn't match at '%s' (line %s, column %s)." % (
                 rule_name,
                 self.text[self.pos:self.pos + 20],
                 self.line(),
@@ -32,31 +36,47 @@ def line(self):
         match."""
         # This is a method rather than a property in case we ever wanted to
         # pass in which line endings we want to use.
-        return self.text.count('\n', 0, self.pos) + 1
+        if isinstance(self.text, list):  # TokenGrammar
+            return None
+        else:
+            return self.text.count('\n', 0, self.pos) + 1
 
     def column(self):
         """Return the 1-based column where the expression ceased to match."""
         # We choose 1-based because that's what Python does with SyntaxErrors.
         try:
             return self.pos - self.text.rindex('\n', 0, self.pos)
-        except ValueError:
+        except (ValueError, AttributeError):
             return self.pos + 1
 
 
-@python_2_unicode_compatible
+class LeftRecursionError(ParseError):
+    def __str__(self):
+        rule_name = self.expr.name if self.expr.name else str(self.expr)
+        window = self.text[self.pos:self.pos + 20]
+        return dedent(f"""
+            Left recursion in rule {rule_name!r} at {window!r} (line {self.line()}, column {self.column()}).
+
+            Parsimonious is a packrat parser, so it can't handle left recursion.
+            See https://en.wikipedia.org/wiki/Parsing_expression_grammar#Indirect_left_recursion
+            for how to rewrite your grammar into a rule that does not use left-recursion.
+            """
+        ).strip()
+
+
 class IncompleteParseError(ParseError):
     """A call to ``parse()`` matched a whole Expression but did not consume the
     entire text."""
 
     def __str__(self):
-        return u"Rule '%s' matched in its entirety, but it didn't consume all the text. The non-matching portion of the text begins with '%s' (line %s, column %s)." % (
+        return "Rule '%s' matched in its entirety, but it didn't consume all the text. The non-matching portion of the text begins with '%s' (line %s, column %s)." % (
                 self.expr.name,
                 self.text[self.pos:self.pos + 20],
                 self.line(),
                 self.column())
 
 
-class VisitationError(Exception):
+class VisitationError(ParsimoniousError):
     """Something went wrong while traversing a parse tree.
 
     This exception exists to augment an underlying exception with information
@@ -76,7 +96,7 @@ def __init__(self, exc, exc_class, node):
 
         """
         self.original_class = exc_class
-        super(VisitationError, self).__init__(
+        super().__init__(
             '%s: %s\n\n'
             'Parse tree:\n'
             '%s' %
@@ -85,7 +105,7 @@ def __init__(self, exc, exc_class, node):
              node.prettily(error=node)))
 
 
-class BadGrammar(StrAndRepr, Exception):
+class BadGrammar(StrAndRepr, ParsimoniousError):
     """Something was wrong with the definition of a grammar.
 
     Note that a ParseError might be raised instead if the error is in the
@@ -94,7 +114,6 @@ class BadGrammar(StrAndRepr, Exception):
     """
 
 
-@python_2_unicode_compatible
 class UndefinedLabel(BadGrammar):
     """A rule referenced in a grammar was never defined.
 
@@ -106,4 +125,4 @@ def __init__(self, label):
         self.label = label
 
     def __str__(self):
-        return u'The label "%s" was never defined.' % self.label
+        return 'The label "%s" was never defined.' % self.label