add an example for lazy "per-directory" setup.

--HG--
branch : trunk

example/funcarg/lazysetup/conftest.py

@@ -0,0 +1,22 @@
+
+class ConftestPlugin:
+    def pytest_configure(self, config):
+        self._setup = None
+
+    def pytest_funcarg__setup(self, request):
+        if self._setup is None:
+            self._setup = LazySetup()
+        return self._setup
+
+    def pytest_unconfigure(self, config):
+        if self._setup is not None:
+            self._setup.finalize()
+
+class LazySetup:
+    def __init__(self):
+        import time
+        time.sleep(5)
+        self.timecostly = 1
+
+    def finalize(self):
+        del self.timecostly 

example/funcarg/lazysetup/sub1/test_one.py

@@ -0,0 +1,6 @@
+
+def test_something(setup):
+    assert setup.timecostly == 1
+
+def test_something_more(setup):
+    assert setup.timecostly == 1

example/funcarg/lazysetup/sub2/test_two.py

@@ -0,0 +1,3 @@
+
+def test_quick():
+    pass