check the number of boolean expressions in if statement is reasonnable

--max-bool-expr option allows to configure it (by default, up to 5 are
tolerated)

closes issue #677

2 files changed, 24 insertions, 0 deletions

diff --git a/pylint/test/functional/too_many_boolean_expressions.py b/pylint/test/functional/too_many_boolean_expressions.py
new file mode 100644
index 0000000..b3dc238
--- /dev/null
+++ b/pylint/test/functional/too_many_boolean_expressions.py
@@ -0,0 +1,20 @@
+"""Checks for if statements containing too many boolean expressions"""
+
+# pylint: disable=invalid-name
+
+x = y = z = 5
+if x > -5 and x < 5 and y > -5 and y < 5 and z > -5 and z < 5:  # [too-many-boolean-expressions]
+    pass
+elif True and False and 1 and 2 and 3:
+    pass
+elif True and False and 1 and 2 and 3 and 4 and 5: # [too-many-boolean-expressions]
+    pass
+elif True and (True and True) and (x == 5 or True or True): # [too-many-boolean-expressions]
+    pass
+elif True and (True or (x > -5 and x < 5 and (z > -5 or z < 5))): # [too-many-boolean-expressions]
+    pass
+elif True == True == True == True == True == True:
+    pass
+
+if True and False and 1 and 2 and 3:
+    pass
diff --git a/pylint/test/functional/too_many_boolean_expressions.txt b/pylint/test/functional/too_many_boolean_expressions.txt
new file mode 100644
index 0000000..0bb0086
--- /dev/null
+++ b/pylint/test/functional/too_many_boolean_expressions.txt
@@ -0,0 +1,4 @@
+too-many-boolean-expressions:6::Too many boolean expressions in if statement (6/5)
+too-many-boolean-expressions:10::Too many boolean expressions in if statement (7/5)
+too-many-boolean-expressions:12::Too many boolean expressions in if statement (6/5)
+too-many-boolean-expressions:14::Too many boolean expressions in if statement (6/5)