astprettier 0.1

Pretty print the output of python stdlib `ast.parse`.

astprettier

Pretty print the output of Python AST ast.parse.

Note: This is a fork of astpretty. The goals of this fork are:

• Adding more advanced features that go beyond the REPL scope of astpretty
• Refactoring and cleanup to make the very small code base easier to understand and maintain
• Experimentation with Python packaging to make the project directory more beautiful and have less boilerplate

Installation

pip install astprettier

Usage

REPL

astprettier provides two main functions:

astprettier.format(node, indent_level=0, indent=' ', show_offsets=True, ns_prefix='') astprettier.print(node, indent_level=0, indent=' ', show_offsets=True, ns_prefix='')

astprettier.print is a thin wrapper around astprettier.format that just writes the output of format to sys.stdout

>>> import ast, astprettier
>>> astprettier.print(ast.parse('if x == y: y += 4').body[0])
If(
    lineno=1,
    col_offset=0,
    test=Compare(
        lineno=1,
        col_offset=3,
        left=Name(lineno=1, col_offset=3, id='x', ctx=Load()),
        ops=[Eq()],
        comparators=[Name(lineno=1, col_offset=8, id='y', ctx=Load())],
    ),
    body=[
        AugAssign(
            lineno=1,
            col_offset=11,
            target=Name(lineno=1, col_offset=11, id='y', ctx=Store()),
            op=Add(),
            value=Num(lineno=1, col_offset=16, n=4),
        ),
    ],
    orelse=[],
)

>>> # Comparison with ast.dump()
>>> ast.dump(ast.parse('if x == y: y += 4').body[0])
"If(test=Compare(left=Name(id='x', ctx=Load()), ops=[Eq()], comparators=[Name(id='y', ctx=Load())]), body=[AugAssign(target=Name(id='y', ctx=Store()), op=Add(), value=Constant(value=4))], orelse=[])"

ns_prefix controls whether objects from the ast module will be prefixed with your ast namespace:

>>> astprettier.print(ast.parse('x += 5').body[0], show_offsets=False, ns_prefix='ast')
ast.AugAssign(
    target=ast.Name(id='x', ctx=ast.Store()),
    op=ast.Add(),
    value=ast.Num(n=5),
)

Script

$ python -m astprettier ./setup.py
Module(
    body=[
        ImportFrom(
            lineno=1,
            col_offset=0,
            end_lineno=1,
            end_col_offset=28,
            module='setuptools',
            names=[alias(name='setup', asname=None)],
            level=0,
        ),
        Expr(
            lineno=2,
            col_offset=0,
            end_lineno=2,
            end_col_offset=7,
            value=Call(
                lineno=2,
                col_offset=0,
                end_lineno=2,
                end_col_offset=7,
                func=Name(lineno=2, col_offset=0, end_lineno=2, end_col_offset=5, id='setup', ctx=Load()),
                args=[],
                keywords=[],
            ),
        ),
    ],
    type_ignores=[],
)

Contributing

We love contributions!

astprettier is open source, built on open source, and we'd love to have you hang out in our community.