[3.8] bpo-37950: Fix ast.dump() when call with incompletely initialized node. (GH-15510) (GH-15582)
(cherry picked from commit e64f948e762a6b9fd02e2902ccf42438df6fcb61)
diff --git a/Lib/ast.py b/Lib/ast.py
index da47825..b45f1e4 100644
--- a/Lib/ast.py
+++ b/Lib/ast.py
@@ -98,26 +98,35 @@
def dump(node, annotate_fields=True, include_attributes=False):
"""
- Return a formatted dump of the tree in *node*. This is mainly useful for
- debugging purposes. The returned string will show the names and the values
- for fields. This makes the code impossible to evaluate, so if evaluation is
- wanted *annotate_fields* must be set to False. Attributes such as line
+ Return a formatted dump of the tree in node. This is mainly useful for
+ debugging purposes. If annotate_fields is true (by default),
+ the returned string will show the names and the values for fields.
+ If annotate_fields is false, the result string will be more compact by
+ omitting unambiguous field names. Attributes such as line
numbers and column offsets are not dumped by default. If this is wanted,
- *include_attributes* can be set to True.
+ include_attributes can be set to true.
"""
def _format(node):
if isinstance(node, AST):
- fields = [(a, _format(b)) for a, b in iter_fields(node)]
- rv = '%s(%s' % (node.__class__.__name__, ', '.join(
- ('%s=%s' % field for field in fields)
- if annotate_fields else
- (b for a, b in fields)
- ))
+ args = []
+ keywords = annotate_fields
+ for field in node._fields:
+ try:
+ value = getattr(node, field)
+ except AttributeError:
+ keywords = True
+ else:
+ if keywords:
+ args.append('%s=%s' % (field, _format(value)))
+ else:
+ args.append(_format(value))
if include_attributes and node._attributes:
- rv += fields and ', ' or ' '
- rv += ', '.join('%s=%s' % (a, _format(getattr(node, a)))
- for a in node._attributes)
- return rv + ')'
+ for a in node._attributes:
+ try:
+ args.append('%s=%s' % (a, _format(getattr(node, a))))
+ except AttributeError:
+ pass
+ return '%s(%s)' % (node.__class__.__name__, ', '.join(args))
elif isinstance(node, list):
return '[%s]' % ', '.join(_format(x) for x in node)
return repr(node)