Add basic coverage reporting for RPC tests

Thanks to @MarcoFalke @dexX7 @laanwj for review.

qa/rpc-tests/test_framework/test_framework.py

@@ -13,8 +13,20 @@ import shutil
 import tempfile
 import traceback
 
+from .util import (
+    initialize_chain,
+    assert_equal,
+    start_nodes,
+    connect_nodes_bi,
+    sync_blocks,
+    sync_mempools,
+    stop_nodes,
+    wait_bitcoinds,
+    enable_coverage,
+    check_json_precision,
+    initialize_chain_clean,
+)
 from authproxy import AuthServiceProxy, JSONRPCException
-from util import *
 
 
 class BitcoinTestFramework(object):
@@ -96,6 +108,8 @@ class BitcoinTestFramework(object):
                           help="Root directory for datadirs")
         parser.add_option("--tracerpc", dest="trace_rpc", default=False, action="store_true",
                           help="Print out all RPC calls as they are made")
+        parser.add_option("--coveragedir", dest="coveragedir",
+                          help="Write tested RPC commands into this directory")
         self.add_options(parser)
         (self.options, self.args) = parser.parse_args()
 
@@ -103,6 +117,9 @@ class BitcoinTestFramework(object):
             import logging
             logging.basicConfig(level=logging.DEBUG)
 
+        if self.options.coveragedir:
+            enable_coverage(self.options.coveragedir)
+
         os.environ['PATH'] = self.options.srcdir+":"+os.environ['PATH']
 
         check_json_precision()
@@ -173,7 +190,8 @@ class ComparisonTestFramework(BitcoinTestFramework):
         initialize_chain_clean(self.options.tmpdir, self.num_nodes)
 
     def setup_network(self):
-        self.nodes = start_nodes(self.num_nodes, self.options.tmpdir,
-                                    extra_args=[['-debug', '-whitelist=127.0.0.1']] * self.num_nodes,
-                                    binary=[self.options.testbinary] +
-                                           [self.options.refbinary]*(self.num_nodes-1))
+        self.nodes = start_nodes(
+            self.num_nodes, self.options.tmpdir,
+            extra_args=[['-debug', '-whitelist=127.0.0.1']] * self.num_nodes,
+            binary=[self.options.testbinary] +
+            [self.options.refbinary]*(self.num_nodes-1))