Remove pytest-benchmark dependency

skip benchmarks if not installed (e.g. on Travis)

setup.py

@@ -29,7 +29,6 @@ def run_tests(self):
 
 test_requirements = [
     'pytest',
-    'pytest-benchmark'
 ]
 
 setup(

tests/test_benchmark.py

@@ -7,6 +7,21 @@
 from rlp.exceptions import DecodingError, DeserializationError
 
 
+try:
+    import pytest_benchmark
+except ImportError:
+    do_benchmark = False
+else:
+    do_benchmark = True
+
+
+# speed up setup in case tests aren't run anyway
+if do_benchmark:
+    SIZE = int(1e6)
+else:
+    SIZE = 1
+
+
 class Message(rlp.Serializable):
 
     fields = [
@@ -16,9 +31,6 @@ class Message(rlp.Serializable):
     ]
 
 
-SIZE = int(1e6)
-
-
 def lazy_test_factory(s, valid):
     @pytest.mark.benchmark(group='lazy')
     def f(benchmark):
@@ -77,8 +89,8 @@ def generate_test_functions():
 
     current_module = sys.modules[__name__]
     for rlp_string, valid, name in zip(rlp_strings, valids, names):
-        f_eager = eager_test_factory(rlp_string, valid)
-        f_lazy = lazy_test_factory(rlp_string, valid)
+        f_eager = pytest.mark.skipif('not do_benchmark')(eager_test_factory(rlp_string, valid))
+        f_lazy = pytest.mark.skipif('not do_benchmark')(lazy_test_factory(rlp_string, valid))
         setattr(current_module, 'test_eager_' + name, f_eager)
         setattr(current_module, 'test_lazy_' + name, f_lazy)