[qa] Sort scripts by time for pull_tester and don't overwrite setup_chain

qa/pull-tester/rpc-tests.py

@@ -110,6 +110,8 @@ testScripts = [
     'receivedby.py',
     'mempool_resurrect_test.py',
     'txn_doublespend.py --mineblock',
+    'p2p-segwit.py',
+    'segwit.py',
     'txn_clone.py',
     'getchaintips.py',
     'rawtransactions.py',
@@ -131,13 +133,12 @@ testScripts = [
     'disablewallet.py',
     'sendheaders.py',
     'keypool.py',
+    'p2p-mempool.py',
     'prioritise_transaction.py',
     'invalidblockrequest.py',
     'invalidtxrequest.py',
     'abandonconflict.py',
     'p2p-versionbits-warning.py',
-    'p2p-segwit.py',
-    'segwit.py',
     'importprunedfunds.py',
     'signmessages.py',
 ]

qa/rpc-tests/p2p-mempool.py

@@ -72,8 +72,11 @@ class TestNode(NodeConnCB):
         self.send_message(msg_mempool())
 
 class P2PMempoolTests(BitcoinTestFramework):
-    def setup_chain(self):
-        initialize_chain_clean(self.options.tmpdir, 2)
+
+    def __init__(self):
+        super().__init__()
+        self.setup_clean_chain = True
+        self.num_nodes = 2
 
     def setup_network(self):
         # Start a node with maxuploadtarget of 200 MB (/24h)

qa/rpc-tests/p2p-segwit.py

@@ -163,8 +163,11 @@ class UTXO(object):
 
 
 class SegWitTest(BitcoinTestFramework):
-    def setup_chain(self):
-        initialize_chain_clean(self.options.tmpdir, 3)
+
+    def __init__(self):
+        super().__init__()
+        self.setup_clean_chain = True
+        self.num_nodes = 3
 
     def add_options(self, parser):
         parser.add_option("--oldbinary", dest="oldbinary",

qa/rpc-tests/segwit.py

@@ -71,9 +71,10 @@ def getutxo(txid):
 
 class SegWitTest(BitcoinTestFramework):
 
-    def setup_chain(self):
-        print("Initializing test directory "+self.options.tmpdir)
-        initialize_chain_clean(self.options.tmpdir, 3)
+    def __init__(self):
+        super().__init__()
+        self.setup_clean_chain = True
+        self.num_nodes = 3
 
     def setup_network(self):
         self.nodes = []