bpo-36917: Add default implementation of ast.NodeVisitor.visit_Constant(). (GH-15490)
It emits a deprecation warning and calls corresponding method
visit_Num(), visit_Str(), etc.
diff --git a/Lib/test/test_ast.py b/Lib/test/test_ast.py
index f35d9e6..3d12397 100644
--- a/Lib/test/test_ast.py
+++ b/Lib/test/test_ast.py
@@ -3,6 +3,7 @@
import os
import sys
import unittest
+import warnings
import weakref
from textwrap import dedent
@@ -1662,6 +1663,56 @@
self.assertEqual(ast.get_source_segment(s, cdef.body[0], padded=True), s_method)
+class NodeVisitorTests(unittest.TestCase):
+ def test_old_constant_nodes(self):
+ class Visitor(ast.NodeVisitor):
+ def visit_Num(self, node):
+ log.append((node.lineno, 'Num', node.n))
+ def visit_Str(self, node):
+ log.append((node.lineno, 'Str', node.s))
+ def visit_Bytes(self, node):
+ log.append((node.lineno, 'Bytes', node.s))
+ def visit_NameConstant(self, node):
+ log.append((node.lineno, 'NameConstant', node.value))
+ def visit_Ellipsis(self, node):
+ log.append((node.lineno, 'Ellipsis', ...))
+ mod = ast.parse(dedent('''\
+ i = 42
+ f = 4.25
+ c = 4.25j
+ s = 'string'
+ b = b'bytes'
+ t = True
+ n = None
+ e = ...
+ '''))
+ visitor = Visitor()
+ log = []
+ with warnings.catch_warnings(record=True) as wlog:
+ warnings.filterwarnings('always', '', DeprecationWarning)
+ visitor.visit(mod)
+ self.assertEqual(log, [
+ (1, 'Num', 42),
+ (2, 'Num', 4.25),
+ (3, 'Num', 4.25j),
+ (4, 'Str', 'string'),
+ (5, 'Bytes', b'bytes'),
+ (6, 'NameConstant', True),
+ (7, 'NameConstant', None),
+ (8, 'Ellipsis', ...),
+ ])
+ self.assertEqual([str(w.message) for w in wlog], [
+ 'visit_Num is deprecated; add visit_Constant',
+ 'visit_Num is deprecated; add visit_Constant',
+ 'visit_Num is deprecated; add visit_Constant',
+ 'visit_Str is deprecated; add visit_Constant',
+ 'visit_Bytes is deprecated; add visit_Constant',
+ 'visit_NameConstant is deprecated; add visit_Constant',
+ 'visit_NameConstant is deprecated; add visit_Constant',
+ 'visit_Ellipsis is deprecated; add visit_Constant',
+ ])
+
+
def main():
if __name__ != '__main__':
return