v0.2; work around CPython bug

Author: Zac-HD

Diff for: CHANGELOG.md

@@ -1,5 +1,10 @@
 # Changelog
 
+### 0.2.0 - 2021-11-27
+- More efficient generation of Python identifiers
+- Workaround for [CPython parser bug in 3.9.8](https://bugs.python.org/issue45738) (#16)
+  Yes, *yet another* one - still, that's why `hypothesmith` exists...
+
 ### 0.1.9 - 2021-08-19
 - Fixed rare internal error when `from_node()` generated misplaced `except:` clauses
 

Diff for: src/hypothesmith/__init__.py

@@ -3,5 +3,5 @@
 from hypothesmith.cst import from_node
 from hypothesmith.syntactic import from_grammar
 
-__version__ = "0.1.9"
+__version__ = "0.2.0"
 __all__ = ["from_grammar", "from_node"]

Diff for: src/hypothesmith/syntactic.py

@@ -127,9 +127,15 @@ def draw_symbol(self, data, symbol, draw_state):  # type: ignore
                 # of bizzare errors in CPython, especially with the new PEG parser,
                 # and so we maintain this extra clause to ensure that we get a decent
                 # error message out of it.
-                if isinstance(err, SystemError) and sys.version_info[:3] == (3, 9, 0):
+                if isinstance(err, SystemError) and (
+                    sys.version_info[:3] == (3, 9, 0)
+                    or sys.version_info[:3] >= (3, 9, 8)
+                    and str(err) == "Negative size passed to PyUnicode_New"
+                ):
                     # We've triggered https://bugs.python.org/issue42218 - it's been
                     # fixed upstream, so we'll treat it as if it were a SyntaxError.
+                    # Or the new https://bugs.python.org/issue45738 which makes me
+                    # wish CPython would start running proptests in CI already.
                     assume(False)
                 source_code = ascii("".join(draw_state.result[count:]))
                 raise type(err)(