Merge #15485: add rpc_misc.py, mv test getmemoryinfo, add test mallocinfo

f13ad1cae0 modify test for memory locked in case locking pages failed at some point (Adam Jonas)
2fa85ebd1c add rpc_misc.py, mv test getmemoryinfo, add test mallocinfo (Adam Jonas)

Pull request description:

  Creating the `rpc_misc.py` functional test file to add space for adding tests to a file that doesn't have a lot of coverage.
    - Removing the `getmemoryinfo()` smoke test from wallet basic rather than moving it to keep the wallet decoupled. Feel like testing for reasonable memory allocation values should suffice.
    - Adding coverage for `mallocinfo()`. Introduced standard lib XML parser since the function exports an XML string that describes the current state of the memory-allocation implementation in the caller.

Tree-SHA512: ced30115622916c88d1e729969ee331272ec9f2881eb36dee4bb7331bf633a6810a57fed63a0cfaf86de698edb5162e6a035efd07c89ece1df56b69d61288072

test/functional/rpc_misc.py

@@ -0,0 +1,50 @@
+#!/usr/bin/env python3
+# Copyright (c) 2019 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+"""Test RPC misc output."""
+import xml.etree.ElementTree as ET
+
+from test_framework.test_framework import BitcoinTestFramework
+from test_framework.util import (
+    assert_raises_rpc_error,
+    assert_equal,
+    assert_greater_than,
+    assert_greater_than_or_equal,
+)
+
+from test_framework.authproxy import JSONRPCException
+
+
+class RpcMiscTest(BitcoinTestFramework):
+    def set_test_params(self):
+        self.num_nodes = 1
+
+    def run_test(self):
+        node = self.nodes[0]
+
+        self.log.info("test getmemoryinfo")
+        memory = node.getmemoryinfo()['locked']
+        assert_greater_than(memory['used'], 0)
+        assert_greater_than(memory['free'], 0)
+        assert_greater_than(memory['total'], 0)
+        # assert_greater_than_or_equal() for locked in case locking pages failed at some point
+        assert_greater_than_or_equal(memory['locked'], 0)
+        assert_greater_than(memory['chunks_used'], 0)
+        assert_greater_than(memory['chunks_free'], 0)
+        assert_equal(memory['used'] + memory['free'], memory['total'])
+
+        self.log.info("test mallocinfo")
+        try:
+            mallocinfo = node.getmemoryinfo(mode="mallocinfo")
+            self.log.info('getmemoryinfo(mode="mallocinfo") call succeeded')
+            tree = ET.fromstring(mallocinfo)
+            assert_equal(tree.tag, 'malloc')
+        except JSONRPCException:
+            self.log.info('getmemoryinfo(mode="mallocinfo") not available')
+            assert_raises_rpc_error(-8, 'mallocinfo is only available when compiled with glibc 2.10+', node.getmemoryinfo, mode="mallocinfo")
+
+        assert_raises_rpc_error(-8, "unknown mode foobar", node.getmemoryinfo, mode="foobar")
+
+if __name__ == '__main__':
+    RpcMiscTest().main()

test/functional/test_runner.py

@@ -106,6 +106,7 @@ BASE_SCRIPTS = [
     'wallet_txn_doublespend.py --mineblock',
     'wallet_txn_clone.py',
     'rpc_getchaintips.py',
+    'rpc_misc.py',
     'interface_rest.py',
     'mempool_spend_coinbase.py',
     'mempool_reorg.py',