diff --git a/src/config.cpp b/src/config.cpp
index e05cf417b..a56a4a88f 100644
--- a/src/config.cpp
+++ b/src/config.cpp
@@ -1,55 +1,59 @@
 // Copyright (c) 2017 The Bitcoin developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include "config.h"
 #include "chainparams.h"
 #include "consensus/consensus.h"
 #include "globals.h"
 
 GlobalConfig::GlobalConfig() : useCashAddr(false) {}
 
 bool GlobalConfig::SetMaxBlockSize(uint64_t maxBlockSize) {
     // Do not allow maxBlockSize to be set below historic 1MB limit
     // It cannot be equal either because of the "must be big" UAHF rule.
     if (maxBlockSize <= LEGACY_MAX_BLOCK_SIZE) {
         return false;
     }
 
     nMaxBlockSize = maxBlockSize;
     return true;
 }
 
 uint64_t GlobalConfig::GetMaxBlockSize() const {
     return nMaxBlockSize;
 }
 
 bool GlobalConfig::SetBlockPriorityPercentage(int64_t blockPriorityPercentage) {
     // blockPriorityPercentage has to belong to [0..100]
     if ((blockPriorityPercentage < 0) || (blockPriorityPercentage > 100)) {
         return false;
     }
     nBlockPriorityPercentage = blockPriorityPercentage;
     return true;
 }
 
 uint8_t GlobalConfig::GetBlockPriorityPercentage() const {
     return nBlockPriorityPercentage;
 }
 
 const CChainParams &GlobalConfig::GetChainParams() const {
     return Params();
 }
 
 static GlobalConfig gConfig;
 
 const Config &GetConfig() {
     return gConfig;
 }
 
 void GlobalConfig::SetCashAddrEncoding(bool c) {
     useCashAddr = c;
 }
 bool GlobalConfig::UseCashAddrEncoding() const {
     return useCashAddr;
 }
+
+const CChainParams &DummyConfig::GetChainParams() const {
+    return Params(CBaseChainParams::REGTEST);
+}
diff --git a/src/config.h b/src/config.h
index a668a5c52..d6cb2dcce 100644
--- a/src/config.h
+++ b/src/config.h
@@ -1,44 +1,58 @@
 // Copyright (c) 2017 Amaury SÉCHET
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_CONFIG_H
 #define BITCOIN_CONFIG_H
 
 #include <boost/noncopyable.hpp>
 
 #include <cstdint>
 
 class CChainParams;
 
 class Config : public boost::noncopyable {
 public:
     virtual bool SetMaxBlockSize(uint64_t maxBlockSize) = 0;
     virtual uint64_t GetMaxBlockSize() const = 0;
     virtual bool
     SetBlockPriorityPercentage(int64_t blockPriorityPercentage) = 0;
     virtual uint8_t GetBlockPriorityPercentage() const = 0;
     virtual const CChainParams &GetChainParams() const = 0;
     virtual void SetCashAddrEncoding(bool) = 0;
     virtual bool UseCashAddrEncoding() const = 0;
 };
 
 class GlobalConfig final : public Config {
 public:
     GlobalConfig();
     bool SetMaxBlockSize(uint64_t maxBlockSize);
     uint64_t GetMaxBlockSize() const;
     bool SetBlockPriorityPercentage(int64_t blockPriorityPercentage);
     uint8_t GetBlockPriorityPercentage() const;
     const CChainParams &GetChainParams() const;
     void SetCashAddrEncoding(bool) override;
     bool UseCashAddrEncoding() const override;
 
 private:
     bool useCashAddr;
 };
 
+// Dummy for subclassing in unittests
+class DummyConfig : public Config {
+public:
+    bool SetMaxBlockSize(uint64_t maxBlockSize) override { return false; }
+    uint64_t GetMaxBlockSize() const override { return 0; }
+    bool SetBlockPriorityPercentage(int64_t blockPriorityPercentage) override {
+        return false;
+    }
+    uint8_t GetBlockPriorityPercentage() const override { return 0; }
+    const CChainParams &GetChainParams() const override;
+    void SetCashAddrEncoding(bool) override {}
+    bool UseCashAddrEncoding() const override { return false; }
+};
+
 // Temporary woraround.
 const Config &GetConfig();
 
 #endif
diff --git a/src/test/dstencode_tests.cpp b/src/test/dstencode_tests.cpp
index e1df89b4c..6c0cb660e 100644
--- a/src/test/dstencode_tests.cpp
+++ b/src/test/dstencode_tests.cpp
@@ -1,78 +1,69 @@
 // Copyright (c) 2017 The Bitcoin developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include "chainparams.h"
 #include "config.h"
 #include "dstencode.h"
 #include "test/test_bitcoin.h"
 
 #include <boost/test/unit_test.hpp>
 
 namespace {
 
-class DummyCfg : public Config {
+class DstCfgDummy : public DummyConfig {
 public:
-    DummyCfg() : useCashAddr(false) {}
-    virtual bool SetMaxBlockSize(uint64_t maxBlockSize) { return false; }
-    virtual uint64_t GetMaxBlockSize() const { return 0; }
-    virtual bool SetBlockPriorityPercentage(int64_t blockPriorityPercentage) {
-        return false;
-    }
-    virtual uint8_t GetBlockPriorityPercentage() const { return 0; }
-    virtual const CChainParams &GetChainParams() const {
-        return Params(CBaseChainParams::MAIN);
-    }
-    virtual void SetCashAddrEncoding(bool b) { useCashAddr = b; }
-    virtual bool UseCashAddrEncoding() const { return useCashAddr; }
+    DstCfgDummy() : useCashAddr(false) {}
+    void SetCashAddrEncoding(bool b) override { useCashAddr = b; }
+    bool UseCashAddrEncoding() const override { return useCashAddr; }
 
 private:
     bool useCashAddr;
 };
 
 } // anon ns
 
 BOOST_FIXTURE_TEST_SUITE(dstencode_tests, BasicTestingSetup)
 
 BOOST_AUTO_TEST_CASE(test_addresses) {
     std::vector<uint8_t> hash = {118, 160, 64,  83,  189, 160, 168,
                                  139, 218, 81,  119, 184, 106, 21,
                                  195, 178, 159, 85,  152, 115};
 
     const CTxDestination dstKey = CKeyID(uint160(hash));
     const CTxDestination dstScript = CScriptID(uint160(hash));
 
     std::string cashaddr_pubkey =
         "bitcoincash:qpm2qsznhks23z7629mms6s4cwef74vcwvy22gdx6a";
     std::string cashaddr_script =
         "bitcoincash:ppm2qsznhks23z7629mms6s4cwef74vcwvn0h829pq";
     std::string base58_pubkey = "1BpEi6DfDAUFd7GtittLSdBeYJvcoaVggu";
     std::string base58_script = "3CWFddi6m4ndiGyKqzYvsFYagqDLPVMTzC";
 
     const CChainParams &params = Params(CBaseChainParams::MAIN);
-    DummyCfg cfg;
+    DstCfgDummy cfg;
 
     // Check encoding
     cfg.SetCashAddrEncoding(true);
     BOOST_CHECK_EQUAL(cashaddr_pubkey, EncodeDestination(dstKey, params, cfg));
     BOOST_CHECK_EQUAL(cashaddr_script,
                       EncodeDestination(dstScript, params, cfg));
     cfg.SetCashAddrEncoding(false);
     BOOST_CHECK_EQUAL(base58_pubkey, EncodeDestination(dstKey, params, cfg));
     BOOST_CHECK_EQUAL(base58_script, EncodeDestination(dstScript, params, cfg));
 
     // Check decoding
     BOOST_CHECK(dstKey == DecodeDestination(cashaddr_pubkey, params));
     BOOST_CHECK(dstScript == DecodeDestination(cashaddr_script, params));
     BOOST_CHECK(dstKey == DecodeDestination(base58_pubkey, params));
     BOOST_CHECK(dstScript == DecodeDestination(base58_script, params));
 
     // Validation
     BOOST_CHECK(IsValidDestinationString(cashaddr_pubkey, params));
     BOOST_CHECK(IsValidDestinationString(cashaddr_script, params));
     BOOST_CHECK(IsValidDestinationString(base58_pubkey, params));
     BOOST_CHECK(IsValidDestinationString(base58_script, params));
     BOOST_CHECK(!IsValidDestinationString("notvalid", params));
 }
 
 BOOST_AUTO_TEST_SUITE_END()