1 files changed, 53 insertions, 0 deletions
diff --git a/tests/functional/u/unnecessary/unnecessary_lambda.py b/tests/functional/u/unnecessary/unnecessary_lambda.py
new file mode 100644
index 000000000..91f6bf86d
--- /dev/null
+++ b/tests/functional/u/unnecessary/unnecessary_lambda.py
@@ -0,0 +1,53 @@
+# pylint: disable=undefined-variable, use-list-literal
+"""test suspicious lambda expressions
+"""
+
+__revision__ = ''
+
+# Some simple examples of the most commonly encountered forms.
+# +1: [unnecessary-lambda]
+_ = lambda: list()  # replaceable with "list"
+# +1: [unnecessary-lambda]
+_ = lambda x: hash(x)  # replaceable with "hash"
+# +1: [unnecessary-lambda]
+_ = lambda x, y: min(x, y)  # replaceable with "min"
+
+# A function that can take any arguments given to it.
+_ANYARGS = lambda *args, **kwargs: 'completely arbitrary return value'
+
+# Some more complex forms of unnecessary lambda expressions.
+# +1: [unnecessary-lambda]
+_ = lambda *args: _ANYARGS(*args)
+# +1: [unnecessary-lambda]
+_ = lambda **kwargs: _ANYARGS(**kwargs)
+# +1: [unnecessary-lambda]
+_ = lambda *args, **kwargs: _ANYARGS(*args, **kwargs)
+# +1: [unnecessary-lambda]
+_ = lambda x, y, z, *args, **kwargs: _ANYARGS(x, y, z, *args, **kwargs)
+
+# Lambdas that are *not* unnecessary and should *not* trigger warnings.
+_ = lambda x: x
+_ = lambda x: x()
+_ = lambda x=4: hash(x)
+_ = lambda x, y: list(range(y, x))
+_ = lambda x: list(range(5, x))
+_ = lambda x, y: list(range(x, 5))
+_ = lambda x, y, z: x.y(z)
+_ = lambda: 5
+_ = lambda **kwargs: _ANYARGS()
+_ = lambda **kwargs: _ANYARGS(**dict([('three', 3)]))
+_ = lambda **kwargs: _ANYARGS(**{'three': 3})
+_ = lambda dict_arg, **kwargs: _ANYARGS(kwargs, **dict_arg)
+_ = lambda *args: _ANYARGS()
+_ = lambda *args: _ANYARGS(*list([3, 4]))
+_ = lambda *args: _ANYARGS(*[3, 4])
+_ = lambda list_arg, *args: _ANYARGS(args, *list_arg)
+_ = lambda: _ANYARGS(*[3])
+_ = lambda: _ANYARGS(**{'three': 3})
+_ = lambda: _ANYARGS(*[3], **{'three': 3})
+_ = lambda: _ANYARGS(func=42)
+
+# Don't warn about this.
+_ = lambda: code().analysis()
+
+_ = lambda **kwargs: dict(bar=42, **kwargs)