black/tests/data/debug_visitor.py
2018-06-06 15:48:38 -07:00

33 lines
1.2 KiB
Python

@dataclass
class DebugVisitor(Visitor[T]):
tree_depth: int = 0
def visit_default(self, node: LN) -> Iterator[T]:
indent = ' ' * (2 * self.tree_depth)
if isinstance(node, Node):
_type = type_repr(node.type)
out(f'{indent}{_type}', fg='yellow')
self.tree_depth += 1
for child in node.children:
yield from self.visit(child)
self.tree_depth -= 1
out(f'{indent}/{_type}', fg='yellow', bold=False)
else:
_type = token.tok_name.get(node.type, str(node.type))
out(f'{indent}{_type}', fg='blue', nl=False)
if node.prefix:
# We don't have to handle prefixes for `Node` objects since
# that delegates to the first child anyway.
out(f' {node.prefix!r}', fg='green', bold=False, nl=False)
out(f' {node.value!r}', fg='blue', bold=False)
@classmethod
def show(cls, code: str) -> None:
"""Pretty-prints a given string of `code`.
Convenience method for debugging.
"""
v: DebugVisitor[None] = DebugVisitor()
list(v.visit(lib2to3_parse(code)))