Implement --setup-plan option

testing/python/setup_plan.py

@@ -0,0 +1,18 @@
+def test_show_fixtures_and_test(testdir):
+    p = testdir.makepyfile('''
+        import pytest
+        @pytest.fixture
+        def arg():
+            assert False
+        def test_arg(arg):
+            assert False
+    ''')
+
+    result = testdir.runpytest("--setup-plan", p)
+    assert result.ret == 0
+
+    result.stdout.fnmatch_lines([
+        '*SETUP    F arg*',
+        '*test_arg (fixtures used: arg)',
+        '*TEARDOWN F arg*',
+    ])