From b821173b5458d137c8d5edb6e9b4997aac800a38 Mon Sep 17 00:00:00 2001 From: Dong-hee Na Date: Wed, 8 Jan 2020 02:30:55 +0900 Subject: bpo-38871: Fix lib2to3 for filter-based statements that contain lambda (GH-17780) Correctly parenthesize filter-based statements that contain lambda expressions in lib2to3. --- Lib/lib2to3/fixes/fix_filter.py | 10 +++++++--- Lib/lib2to3/tests/test_fixers.py | 5 +++++ .../next/Library/2020-01-01-18-44-52.bpo-38871.3EEOLg.rst | 2 ++ 3 files changed, 14 insertions(+), 3 deletions(-) create mode 100644 Misc/NEWS.d/next/Library/2020-01-01-18-44-52.bpo-38871.3EEOLg.rst diff --git a/Lib/lib2to3/fixes/fix_filter.py b/Lib/lib2to3/fixes/fix_filter.py index a7a5a15..38e9078 100644 --- a/Lib/lib2to3/fixes/fix_filter.py +++ b/Lib/lib2to3/fixes/fix_filter.py @@ -17,7 +17,7 @@ Python 2.6 figure it out. from .. import fixer_base from ..pytree import Node from ..pygram import python_symbols as syms -from ..fixer_util import Name, ArgList, ListComp, in_special_context +from ..fixer_util import Name, ArgList, ListComp, in_special_context, parenthesize class FixFilter(fixer_base.ConditionalFix): @@ -65,10 +65,14 @@ class FixFilter(fixer_base.ConditionalFix): trailers.append(t.clone()) if "filter_lambda" in results: + xp = results.get("xp").clone() + if xp.type == syms.test: + xp.prefix = "" + xp = parenthesize(xp) + new = ListComp(results.get("fp").clone(), results.get("fp").clone(), - results.get("it").clone(), - results.get("xp").clone()) + results.get("it").clone(), xp) new = Node(syms.power, [new] + trailers, prefix="") elif "none" in results: diff --git a/Lib/lib2to3/tests/test_fixers.py b/Lib/lib2to3/tests/test_fixers.py index 3da5dd8..a285241 100644 --- a/Lib/lib2to3/tests/test_fixers.py +++ b/Lib/lib2to3/tests/test_fixers.py @@ -2954,6 +2954,11 @@ class Test_filter(FixerTestCase): a = """x = [x for x in range(10) if x%2 == 0]""" self.check(b, a) + # bpo-38871 + b = """filter(lambda x: True if x > 2 else False, [1, 2, 3])""" + a = """[x for x in [1, 2, 3] if (True if x > 2 else False)]""" + self.check(b, a) + def test_filter_trailers(self): b = """x = filter(None, 'abc')[0]""" a = """x = [_f for _f in 'abc' if _f][0]""" diff --git a/Misc/NEWS.d/next/Library/2020-01-01-18-44-52.bpo-38871.3EEOLg.rst b/Misc/NEWS.d/next/Library/2020-01-01-18-44-52.bpo-38871.3EEOLg.rst new file mode 100644 index 0000000..fe970fd --- /dev/null +++ b/Misc/NEWS.d/next/Library/2020-01-01-18-44-52.bpo-38871.3EEOLg.rst @@ -0,0 +1,2 @@ +Correctly parenthesize filter-based statements that contain lambda +expressions in mod:`lib2to3`. Patch by Dong-hee Na. -- cgit v0.12