pytest: Use pytest fixtures for the test directory and clean it up

The modern, pytest based, tests now clean up after themselves by removing
directories of successful tests and the base directory if there was no failure.

Signed-off-by: Christian Decker <decker.christian@gmail.com>

tests/fixtures.py

@@ -10,7 +10,6 @@ import tempfile
 import utils
 
 
-TEST_DIR = tempfile.mkdtemp(prefix='ltests-')
 VALGRIND = os.getenv("NO_VALGRIND", "0") == "0"
 DEVELOPER = os.getenv("DEVELOPER", "0") == "1"
 TEST_DEBUG = os.getenv("TEST_DEBUG", "0") == "1"
@@ -21,17 +20,32 @@ TEST_DEBUG = os.getenv("TEST_DEBUG", "0") == "1"
 __attempts = {}
 
 
+@pytest.fixture(scope="session")
+def test_base_dir():
+    directory = tempfile.mkdtemp(prefix='ltests-')
+    print("Running tests in {}".format(directory))
+
+    yield directory
+
+    if os.listdir(directory) == []:
+        shutil.rmtree(directory)
+
+
 @pytest.fixture
-def directory(test_name):
+def directory(test_base_dir, test_name):
     """Return a per-test specific directory.
 
     This makes a unique test-directory even if a test is rerun multiple times.
 
     """
-    global TEST_DIR, __attempts
+    global __attempts
     # Auto set value if it isn't in the dict yet
     __attempts[test_name] = __attempts.get(test_name, 0) + 1
-    yield os.path.join(TEST_DIR, "{}_{}".format(test_name, __attempts[test_name]))
+    directory = os.path.join(test_base_dir, "{}_{}".format(test_name, __attempts[test_name]))
+
+    yield directory
+
+    shutil.rmtree(directory)
 
 
 @pytest.fixture
@@ -100,8 +114,6 @@ def node_factory(directory, test_name, bitcoind, executor):
     if not ok:
         raise Exception("At least one lightning exited with unexpected non-zero return code")
 
-    shutil.rmtree(nf.directory)
-
 
 def getValgrindErrors(node):
     for error_file in os.listdir(node.daemon.lightning_dir):

tests/test_lightningd.py

@@ -32,7 +32,6 @@ VALGRIND = os.getenv("NO_VALGRIND", "0") == "0"
 DEVELOPER = os.getenv("DEVELOPER", "0") == "1"
 TEST_DEBUG = os.getenv("TEST_DEBUG", "0") == "1"
 
-print("Testing results are in {}".format(TEST_DIR))
 
 if TEST_DEBUG:
     logging.basicConfig(level=logging.DEBUG, stream=sys.stdout)