Skip to main content

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

Project description

Build Status Coverage Status

astpretty

Pretty print the output of python stdlib ast.parse.

astpretty is intended to be a replacement for ast.dump.

Installation

pip install astpretty

Usage

astpretty provides two api functions:

astpretty.pprint(node, indent=FOUR_SPACE_INDENT, show_offsets=True)

Print a representation of the ast node.

>>> astpretty.pprint(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=[],
)

indent allows control over the indentation string:

>>> astpretty.pprint(ast.parse('if x == y: y += 4').body[0], indent='  ')
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=[],
)

show_offsets controls whether the output includes line / column information:

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

astpretty.pformat(node, indent=FOUR_SPACE_INDENT, show_offsets=True)

Return a string representation of the ast node.

Arguments are identical to astpretty.pprint.

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

Comparison with stdlib ast.dump

>>> print(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=Num(n=4))], orelse=[])

typed-ast support

astpretty works with typed-ast!

For usage with typed-ast make sure you have typed-ast installed, a convenient way to do this is with the typed extra to astpretty:

pip install astpretty[typed]

The apis above work equally well with the return values from the ast modules provided by typed_ast:

>>> import astpretty
>>> from typed_ast import ast3
>>> astpretty.pprint(ast3.parse('x = 4  # type: int'))
Module(
    body=[
        Assign(
            lineno=1,
            col_offset=0,
            targets=[Name(lineno=1, col_offset=0, id='x', ctx=Store())],
            value=Num(lineno=1, col_offset=4, n=4),
            type_comment='int',
        ),
    ],
    type_ignores=[],
)

With typed-ast installed, the commandline interface adds --typed-27 and --typed-3 options for using the alternative ast parsers:

$ astpretty --typed-3 t.py
Module(
    body=[
        Assign(
            lineno=1,
            col_offset=0,
            targets=[Name(lineno=1, col_offset=0, id='x', ctx=Store())],
            value=Num(lineno=1, col_offset=4, n=4),
            type_comment='int',
        ),
    ],
    type_ignores=[],
)

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

astpretty-1.6.0.tar.gz (4.7 kB view hashes)

Uploaded Source

Built Distribution

astpretty-1.6.0-py2.py3-none-any.whl (5.0 kB view hashes)

Uploaded Python 2 Python 3

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page