summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--ChangeLog6
-rw-r--r--doc/whatsnew/2.12.rst6
-rw-r--r--pylint/checkers/base.py19
-rw-r--r--pylint/extensions/comparison_placement.py67
-rw-r--r--pylintrc1
-rw-r--r--tests/checkers/unittest_base.py9
-rw-r--r--tests/extensions/data/compare_to_zero.py2
-rw-r--r--tests/functional/a/assert_on_tuple.py2
-rw-r--r--tests/functional/c/comparison_with_callable.py2
-rw-r--r--tests/functional/c/consider/consider_using_in.py2
-rw-r--r--tests/functional/e/excess_escapes.py2
-rw-r--r--tests/functional/m/misplaced_bare_raise.py1
-rw-r--r--tests/functional/m/misplaced_bare_raise.txt14
-rw-r--r--tests/functional/m/misplaced_comparison_constant.py13
-rw-r--r--tests/functional/m/misplaced_comparison_constant.rc3
-rw-r--r--tests/functional/n/nan_comparison_check.py2
-rw-r--r--tests/functional/s/singleton_comparison.py2
-rw-r--r--tests/functional/u/use/use_implicit_booleaness_not_len.py2
-rw-r--r--tests/functional/u/use/using_constant_test.py1
19 files changed, 112 insertions, 44 deletions
diff --git a/ChangeLog b/ChangeLog
index 96773582c..a4998baf8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -162,6 +162,12 @@ Release date: TBA
Closes #4580
+* Moved ``misplaced-comparison-constant`` to its own extension ``comparison_placement``.
+ This checker was opinionated and now no longer a default. It can be reactived by adding
+ ``pylint.extensions.comparison_placement`` to ``load-plugins`` in your config.
+
+ Closes #1064
+
* A new ``bad-configuration-section`` checker was added that will emit for misplaced option
in pylint's top level namespace for toml configuration. Top-level dictionaries or option defined
in the wrong section will still silently not be taken into account, which is tracked in a
diff --git a/doc/whatsnew/2.12.rst b/doc/whatsnew/2.12.rst
index 59c89ff22..b69af3289 100644
--- a/doc/whatsnew/2.12.rst
+++ b/doc/whatsnew/2.12.rst
@@ -75,6 +75,12 @@ Extensions
Closes #5008
+* Moved ``misplaced-comparison-constant`` to its own extension ``comparison_placement``.
+ This checker was opinionated and now no longer a default. It can be reactived by adding
+ ``pylint.extensions.comparison_placement`` to ``load-plugins`` in your config.
+
+ Closes #1064
+
Other Changes
=============
diff --git a/pylint/checkers/base.py b/pylint/checkers/base.py
index 510b2cdcf..fd18fb867 100644
--- a/pylint/checkers/base.py
+++ b/pylint/checkers/base.py
@@ -214,7 +214,7 @@ DEFAULT_ARGUMENT_SYMBOLS = dict(
)
},
)
-REVERSED_COMPS = {"<": ">", "<=": ">=", ">": "<", ">=": "<="}
+
COMPARISON_OPERATORS = frozenset(("==", "!=", "<", ">", "<=", ">="))
# List of methods which can be redefined
REDEFINABLE_METHODS = frozenset(("__module__",))
@@ -2323,13 +2323,6 @@ class ComparisonChecker(_BasicChecker):
"Used when an expression is compared to singleton "
"values like True, False or None.",
),
- "C0122": (
- "Comparison should be %s",
- "misplaced-comparison-constant",
- "Used when the constant is placed on the left side "
- "of a comparison. It is usually clearer in intent to "
- "place it in the right hand side of the comparison.",
- ),
"C0123": (
"Use isinstance() rather than type() for a typecheck.",
"unidiomatic-typecheck",
@@ -2478,13 +2471,6 @@ class ComparisonChecker(_BasicChecker):
if is_const or is_other_literal:
self.add_message("literal-comparison", node=node)
- def _check_misplaced_constant(self, node, left, right, operator):
- if isinstance(right, nodes.Const):
- return
- operator = REVERSED_COMPS.get(operator, operator)
- suggestion = f"{right.as_string()} {operator} {left.value!r}"
- self.add_message("misplaced-comparison-constant", node=node, args=(suggestion,))
-
def _check_logical_tautology(self, node: nodes.Compare):
"""Check if identifier is compared against itself.
:param node: Compare node
@@ -2532,7 +2518,6 @@ class ComparisonChecker(_BasicChecker):
@utils.check_messages(
"singleton-comparison",
- "misplaced-comparison-constant",
"unidiomatic-typecheck",
"literal-comparison",
"comparison-with-itself",
@@ -2549,8 +2534,6 @@ class ComparisonChecker(_BasicChecker):
left = node.left
operator, right = node.ops[0]
- if operator in COMPARISON_OPERATORS and isinstance(left, nodes.Const):
- self._check_misplaced_constant(node, left, right, operator)
if operator in ("==", "!="):
self._check_singleton_comparison(
diff --git a/pylint/extensions/comparison_placement.py b/pylint/extensions/comparison_placement.py
new file mode 100644
index 000000000..64c8dee5e
--- /dev/null
+++ b/pylint/extensions/comparison_placement.py
@@ -0,0 +1,67 @@
+# Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
+# For details: https://github.com/PyCQA/pylint/blob/main/LICENSE
+
+"""
+Checks for yoda comparisons (variable before constant)
+See https://en.wikipedia.org/wiki/Yoda_conditions
+"""
+
+
+from astroid import nodes
+
+from pylint.checkers import BaseChecker, utils
+from pylint.interfaces import IAstroidChecker
+
+REVERSED_COMPS = {"<": ">", "<=": ">=", ">": "<", ">=": "<="}
+COMPARISON_OPERATORS = frozenset(("==", "!=", "<", ">", "<=", ">="))
+
+
+class MisplacedComparisonConstantChecker(BaseChecker):
+ """Checks the placement of constants in comparisons"""
+
+ __implements__ = (IAstroidChecker,)
+
+ # configuration section name
+ name = "comparison-placement"
+ msgs = {
+ "C2201": (
+ "Comparison should be %s",
+ "misplaced-comparison-constant",
+ "Used when the constant is placed on the left side "
+ "of a comparison. It is usually clearer in intent to "
+ "place it in the right hand side of the comparison.",
+ {"old_names": [("C0122", "old-misplaced-comparison-constant")]},
+ )
+ }
+
+ options = ()
+
+ def _check_misplaced_constant(
+ self,
+ node: nodes.Compare,
+ left: nodes.NodeNG,
+ right: nodes.NodeNG,
+ operator: str,
+ ):
+ if isinstance(right, nodes.Const):
+ return
+ operator = REVERSED_COMPS.get(operator, operator)
+ suggestion = f"{right.as_string()} {operator} {left.value!r}"
+ self.add_message("misplaced-comparison-constant", node=node, args=(suggestion,))
+
+ @utils.check_messages("misplaced-comparison-constant")
+ def visit_compare(self, node: nodes.Compare) -> None:
+ # NOTE: this checker only works with binary comparisons like 'x == 42'
+ # but not 'x == y == 42'
+ if len(node.ops) != 1:
+ return
+
+ left = node.left
+ operator, right = node.ops[0]
+ if operator in COMPARISON_OPERATORS and isinstance(left, nodes.Const):
+ self._check_misplaced_constant(node, left, right, operator)
+
+
+def register(linter):
+ """Required method to auto register this checker."""
+ linter.register_checker(MisplacedComparisonConstantChecker(linter))
diff --git a/pylintrc b/pylintrc
index 8df15f713..95e796939 100644
--- a/pylintrc
+++ b/pylintrc
@@ -24,6 +24,7 @@ load-plugins=
pylint.extensions.overlapping_exceptions,
pylint.extensions.typing,
pylint.extensions.redefined_variable_type,
+ pylint.extensions.comparison_placement,
# Use multiple processes to speed up Pylint.
jobs=1
diff --git a/tests/checkers/unittest_base.py b/tests/checkers/unittest_base.py
index 9f0d5fd4f..46a9913a4 100644
--- a/tests/checkers/unittest_base.py
+++ b/tests/checkers/unittest_base.py
@@ -548,9 +548,6 @@ class TestComparison(CheckerTestCase):
node = astroid.extract_node("True == foo")
messages = (
MessageTest(
- "misplaced-comparison-constant", node=node, args=("foo == True",)
- ),
- MessageTest(
"singleton-comparison",
node=node,
args=(
@@ -565,9 +562,6 @@ class TestComparison(CheckerTestCase):
node = astroid.extract_node("False == foo")
messages = (
MessageTest(
- "misplaced-comparison-constant", node=node, args=("foo == False",)
- ),
- MessageTest(
"singleton-comparison",
node=node,
args=(
@@ -582,9 +576,6 @@ class TestComparison(CheckerTestCase):
node = astroid.extract_node("None == foo")
messages = (
MessageTest(
- "misplaced-comparison-constant", node=node, args=("foo == None",)
- ),
- MessageTest(
"singleton-comparison",
node=node,
args=("'None == foo'", "'None is foo'"),
diff --git a/tests/extensions/data/compare_to_zero.py b/tests/extensions/data/compare_to_zero.py
index dfe6bbcb5..29fd13994 100644
--- a/tests/extensions/data/compare_to_zero.py
+++ b/tests/extensions/data/compare_to_zero.py
@@ -1,4 +1,4 @@
-# pylint: disable=literal-comparison,missing-docstring,misplaced-comparison-constant
+# pylint: disable=literal-comparison,missing-docstring
X = 123
Y = len('test')
diff --git a/tests/functional/a/assert_on_tuple.py b/tests/functional/a/assert_on_tuple.py
index e360737e6..57dbd0907 100644
--- a/tests/functional/a/assert_on_tuple.py
+++ b/tests/functional/a/assert_on_tuple.py
@@ -1,6 +1,6 @@
'''Assert check example'''
-# pylint: disable=misplaced-comparison-constant, comparison-with-itself
+# pylint: disable=comparison-with-itself
assert (1 == 1, 2 == 2), "no error"
assert (1 == 1, 2 == 2) # [assert-on-tuple]
assert 1 == 1, "no error"
diff --git a/tests/functional/c/comparison_with_callable.py b/tests/functional/c/comparison_with_callable.py
index b676844ae..fb02729d8 100644
--- a/tests/functional/c/comparison_with_callable.py
+++ b/tests/functional/c/comparison_with_callable.py
@@ -1,4 +1,4 @@
-# pylint: disable = disallowed-name, missing-docstring, useless-return, misplaced-comparison-constant, invalid-name, no-self-use, line-too-long, useless-object-inheritance
+# pylint: disable = disallowed-name, missing-docstring, useless-return, invalid-name, no-self-use, line-too-long, useless-object-inheritance
def foo():
return None
diff --git a/tests/functional/c/consider/consider_using_in.py b/tests/functional/c/consider/consider_using_in.py
index 7ce5dd0b6..5bc06e438 100644
--- a/tests/functional/c/consider/consider_using_in.py
+++ b/tests/functional/c/consider/consider_using_in.py
@@ -1,4 +1,4 @@
-# pylint: disable=missing-docstring, invalid-name, pointless-statement, misplaced-comparison-constant, undefined-variable, literal-comparison, line-too-long, unneeded-not, too-few-public-methods, use-implicit-booleaness-not-comparison
+# pylint: disable=missing-docstring, invalid-name, pointless-statement, undefined-variable, literal-comparison, line-too-long, unneeded-not, too-few-public-methods, use-implicit-booleaness-not-comparison
value = value1 = 1
value2 = 2
diff --git a/tests/functional/e/excess_escapes.py b/tests/functional/e/excess_escapes.py
index 19fd5cb4d..a81dc7b9a 100644
--- a/tests/functional/e/excess_escapes.py
+++ b/tests/functional/e/excess_escapes.py
@@ -1,4 +1,4 @@
-# pylint:disable=pointless-string-statement, fixme, misplaced-comparison-constant, comparison-with-itself
+# pylint:disable=pointless-string-statement, fixme, comparison-with-itself
"""Stray backslash escapes may be missing a raw-string prefix."""
# pylint: disable=redundant-u-string-prefix
diff --git a/tests/functional/m/misplaced_bare_raise.py b/tests/functional/m/misplaced_bare_raise.py
index 6148733e2..c704f0122 100644
--- a/tests/functional/m/misplaced_bare_raise.py
+++ b/tests/functional/m/misplaced_bare_raise.py
@@ -11,7 +11,6 @@ try:
except Exception:
raise
-# pylint: disable=misplaced-comparison-constant
try:
pass
except Exception:
diff --git a/tests/functional/m/misplaced_bare_raise.txt b/tests/functional/m/misplaced_bare_raise.txt
index 38e04f988..d64ff43cb 100644
--- a/tests/functional/m/misplaced_bare_raise.txt
+++ b/tests/functional/m/misplaced_bare_raise.txt
@@ -1,7 +1,7 @@
-misplaced-bare-raise:5:4::The raise statement is not inside an except clause
-misplaced-bare-raise:36:16:test1.best:The raise statement is not inside an except clause
-misplaced-bare-raise:39:4:test1:The raise statement is not inside an except clause
-misplaced-bare-raise:40:0::The raise statement is not inside an except clause
-misplaced-bare-raise:49:4::The raise statement is not inside an except clause
-misplaced-bare-raise:57:4:A:The raise statement is not inside an except clause
-misplaced-bare-raise:68:4::The raise statement is not inside an except clause
+misplaced-bare-raise:5:4::The raise statement is not inside an except clause:HIGH
+misplaced-bare-raise:35:16:test1.best:The raise statement is not inside an except clause:HIGH
+misplaced-bare-raise:38:4:test1:The raise statement is not inside an except clause:HIGH
+misplaced-bare-raise:39:0::The raise statement is not inside an except clause:HIGH
+misplaced-bare-raise:48:4::The raise statement is not inside an except clause:HIGH
+misplaced-bare-raise:56:4:A:The raise statement is not inside an except clause:HIGH
+misplaced-bare-raise:67:4::The raise statement is not inside an except clause:HIGH
diff --git a/tests/functional/m/misplaced_comparison_constant.py b/tests/functional/m/misplaced_comparison_constant.py
index 29f2b1ed8..0162187bf 100644
--- a/tests/functional/m/misplaced_comparison_constant.py
+++ b/tests/functional/m/misplaced_comparison_constant.py
@@ -34,3 +34,16 @@ def good_comparison():
for i in range(10):
if i == 5:
pass
+
+def double_comparison():
+ """Check that we return early for non-binary comparison"""
+ for i in range(10):
+ if i == 1 == 2:
+ pass
+ if 2 <= i <= 8:
+ print("Between 2 and 8 inclusive")
+
+def const_comparison():
+ """Check that we return early for comparison of two constants"""
+ if 1 == 2:
+ pass
diff --git a/tests/functional/m/misplaced_comparison_constant.rc b/tests/functional/m/misplaced_comparison_constant.rc
new file mode 100644
index 000000000..abe6b9f27
--- /dev/null
+++ b/tests/functional/m/misplaced_comparison_constant.rc
@@ -0,0 +1,3 @@
+[MASTER]
+load-plugins=
+ pylint.extensions.comparison_placement,
diff --git a/tests/functional/n/nan_comparison_check.py b/tests/functional/n/nan_comparison_check.py
index b01cf2636..b9a720b9a 100644
--- a/tests/functional/n/nan_comparison_check.py
+++ b/tests/functional/n/nan_comparison_check.py
@@ -1,4 +1,4 @@
-# pylint: disable=missing-docstring, invalid-name, misplaced-comparison-constant
+# pylint: disable=missing-docstring, invalid-name
# pylint: disable=literal-comparison,comparison-with-itself, import-error
"""Test detection of NaN value comparison."""
import numpy
diff --git a/tests/functional/s/singleton_comparison.py b/tests/functional/s/singleton_comparison.py
index d7ebdaf24..771a1d3cb 100644
--- a/tests/functional/s/singleton_comparison.py
+++ b/tests/functional/s/singleton_comparison.py
@@ -1,4 +1,4 @@
-# pylint: disable=missing-docstring, invalid-name, misplaced-comparison-constant,literal-comparison, comparison-with-itself
+# pylint: disable=missing-docstring, invalid-name, literal-comparison, comparison-with-itself
x = 42
a = x is None
b = x == None # [singleton-comparison]
diff --git a/tests/functional/u/use/use_implicit_booleaness_not_len.py b/tests/functional/u/use/use_implicit_booleaness_not_len.py
index b4107ac2d..fa410a81b 100644
--- a/tests/functional/u/use/use_implicit_booleaness_not_len.py
+++ b/tests/functional/u/use/use_implicit_booleaness_not_len.py
@@ -1,4 +1,4 @@
-# pylint: disable=too-few-public-methods,import-error, missing-docstring, misplaced-comparison-constant
+# pylint: disable=too-few-public-methods,import-error, missing-docstring
# pylint: disable=useless-super-delegation,wrong-import-position,invalid-name, wrong-import-order, condition-evals-to-constant
if len('TEST'): # [use-implicit-booleaness-not-len]
diff --git a/tests/functional/u/use/using_constant_test.py b/tests/functional/u/use/using_constant_test.py
index 74b8a9c1a..ca1ce013c 100644
--- a/tests/functional/u/use/using_constant_test.py
+++ b/tests/functional/u/use/using_constant_test.py
@@ -114,7 +114,6 @@ if not 3:
if instance.method():
pass
-# pylint: disable=misplaced-comparison-constant
if 2 < 3:
pass
View Lorry Controller Status