clear data nodes after run test

tests/helpers/ptrack_helpers.py

@@ -145,6 +145,7 @@ def slow_start(self, replica=False):
 class ProbackupTest(object):
     # Class attributes
     enterprise = is_enterprise()
+    nodes = []
 
     def __init__(self, *args, **kwargs):
         super(ProbackupTest, self).__init__(*args, **kwargs)
@@ -402,7 +403,7 @@ class ProbackupTest(object):
         if node.major_version >= 13:
             self.set_auto_conf(
                 node, {}, 'postgresql.conf', ['wal_keep_segments'])
-
+        self.nodes.append(node)
         return node
 
     def create_tblspace_in_node(self, node, tblspc_name, tblspc_path=None, cfs=False):
@@ -1521,8 +1522,16 @@ class ProbackupTest(object):
         except:
             pass
 
-        for node in nodes:
-            node.stop()
+        if not nodes:
+            nodes = self.nodes
+        for node in list(nodes):
+            try: 
+                if node.status() == 0:
+                    node.stop()
+            except:
+                pass
+            if node in self.nodes:
+                self.nodes.remove(node)
 
         shutil.rmtree(
             os.path.join(