Handle empty Json values:

* Replace Json::Value::isNull() and Json::Value::empty with operator bool()

src/ripple/app/misc/tests/AccountTxPaging.test.cpp

@@ -151,8 +151,8 @@ struct AccountTxPaging_test : beast::unit_test::suite
             expect (next(limit, forward, token, min_ledger, max_ledger) == 1);
             checkTransaction (txs_[0], 5, 7);
 
-            expect(token["ledger"].isNull());
+            expect(! token["ledger"]);
-            expect(token["seq"].isNull());
+            expect(! token["seq"]);
         }
 
         token = Json::nullValue;
@@ -200,8 +200,8 @@ struct AccountTxPaging_test : beast::unit_test::suite
             expect(next(limit, forward, token, min_ledger, max_ledger) == 1);
             checkTransaction (txs_[0], 6, 11);
 
-            expect(token["ledger"].isNull());
+            expect(! token["ledger"]);
-            expect(token["seq"].isNull());
+            expect(! token["seq"]);
         }
 
         token = Json::nullValue;
@@ -241,8 +241,8 @@ struct AccountTxPaging_test : beast::unit_test::suite
             checkTransaction (txs_[2], 3, 5);
         }
 
-        expect (token["ledger"].isNull());
+        expect (! token["ledger"]);
-        expect (token["seq"].isNull());
+        expect (! token["seq"]);
     }
 };
 

src/ripple/app/paths/PathRequest.cpp

@@ -452,7 +452,7 @@ Json::Value PathRequest::doUpdate (RippleLineCache::ref cache, bool fast)
     jvStatus[jss::destination_account] = getApp().accountIDCache().toBase58(*raDstAccount);
     jvStatus[jss::destination_amount] = saDstAmount.getJson (0);
 
-    if (!jvId.isNull ())
+    if (jvId)
         jvStatus["id"] = jvId;
 
     Json::Value jvArray = Json::arrayValue;

src/ripple/json/impl/Object.cpp

@@ -204,7 +204,7 @@ void doCopyFrom (Object& to, Json::Value const& from)
 
 void copyFrom (Json::Value& to, Json::Value const& from)
 {
-    if (to.empty())  // Short circuit this very common case.
+    if (!to)  // Short circuit this very common case.
         to = from;
     else
         doCopyFrom (to, from);

src/ripple/json/impl/json_value.cpp

@@ -822,28 +822,20 @@ Value::size () const
 }
 
 
-bool
+Value::operator bool () const
-Value::empty () const
 {
     if (isNull ())
-        return true;
+        return false;
 
-    if (isString ()) {
+    if (isString ())
+    {
         auto s = asCString();
-        return !(s && strlen(s));
+        return s && strlen(s);
     }
 
-    return (isArray () || isObject ()) && ! size ();
+    return ! (isArray () || isObject ()) || size ();
 }
 
-
-bool
-Value::operator! () const
-{
-    return isNull ();
-}
-
-
 void
 Value::clear ()
 {

src/ripple/json/json_value.h

@@ -253,6 +253,8 @@ public:
     double asDouble () const;
     bool asBool () const;
 
+    /** isNull() tests to see if this field is null.  Don't use this method to
+        test for emptiness: use empty(). */
     bool isNull () const;
     bool isBool () const;
     bool isInt () const;
@@ -269,12 +271,10 @@ public:
     /// Number of values in array or object
     UInt size () const;
 
-    /// \brief Return true if empty array, empty object, or null;
+    /** Returns false if this is an empty array, empty object, empty string,
-    /// otherwise, false.
+        or null. */
-    bool empty () const;
+    explicit
-
+    operator bool() const;
-    /// Return isNull()
-    bool operator! () const;
 
     /// Remove all object members and array elements.
     /// \pre type() is arrayValue, objectValue, or nullValue

src/ripple/json/tests/json_value.test.cpp

@@ -25,30 +25,29 @@
 
 namespace ripple {
 
-class json_value_test : public beast::unit_test::suite
+struct json_value_test : beast::unit_test::suite
 {
-public:
+    void test_bool()
-    void test_empty()
     {
-        expect (Json::Value().empty());
+        expect (! Json::Value());
 
-        expect (Json::Value("").empty());
+        expect (! Json::Value(""));
 
-        expect (! Json::Value("empty").empty());
+        expect (bool (Json::Value("empty")));
-        expect (! Json::Value(false).empty());
+        expect (bool (Json::Value(false)));
-        expect (! Json::Value(true).empty());
+        expect (bool (Json::Value(true)));
-        expect (! Json::Value(0).empty());
+        expect (bool (Json::Value(0)));
-        expect (! Json::Value(1).empty());
+        expect (bool (Json::Value(1)));
 
         Json::Value array (Json::arrayValue);
-        expect (array.empty());
+        expect (! array);
         array.append(0);
-        expect (!array.empty());
+        expect (bool (array));
 
         Json::Value object (Json::objectValue);
-        expect (object.empty());
+        expect (! object);
         object[""] = false;
-        expect (!object.empty());
+        expect (bool (object));
     }
 
     void test_bad_json ()
@@ -148,7 +147,7 @@ public:
         expect (v1.asDouble () == 2.5);
 
         Json::Value v2 = std::move(v1);
-        expect (v1.isNull ());
+        expect (!v1);
         expect (v2.isDouble ());
         expect (v2.asDouble () == 2.5);
         expect (v1 != v2);
@@ -156,7 +155,7 @@ public:
         v1 = std::move(v2);
         expect (v1.isDouble ());
         expect (v1.asDouble () == 2.5);
-        expect (v2.isNull ());
+        expect (! v2);
         expect (v1 != v2);
 
         pass ();
@@ -220,7 +219,7 @@ public:
 
     void run ()
     {
-        test_empty ();
+        test_bool ();
         test_bad_json ();
         test_edge_cases ();
         test_copy ();

src/ripple/net/impl/RPCCall.cpp

@@ -1047,7 +1047,7 @@ struct RPCCallImp
             if (!reader.parse (strData, jvReply))
                 throw std::runtime_error ("couldn't parse reply from server");
 
-            if (jvReply.isNull ())
+            if (!jvReply)
                 throw std::runtime_error ("expected reply to have result, error and id properties");
 
             Json::Value     jvResult (Json::objectValue);

src/ripple/protocol/impl/STParsedJSON.cpp

@@ -532,7 +532,7 @@ static boost::optional<detail::STVar> parseLeaf (
                     AccountID uAccount, uIssuer;
                     Currency uCurrency;
 
-                    if (! account.isNull ())
+                    if (account)
                     {
                         // human account id
                         if (! account.isString ())
@@ -556,7 +556,7 @@ static boost::optional<detail::STVar> parseLeaf (
                         }
                     }
 
-                    if (!currency.isNull ())
+                    if (currency)
                     {
                         // human currency
                         if (!currency.isString ())
@@ -577,7 +577,7 @@ static boost::optional<detail::STVar> parseLeaf (
                         }
                     }
 
-                    if (!issuer.isNull ())
+                    if (issuer)
                     {
                         // human account id
                         if (!issuer.isString ())

src/ripple/protocol/tests/STObject.test.cpp

@@ -44,9 +44,9 @@ public:
     bool parseJSONString (std::string const& json, Json::Value& to)
     {
         Json::Reader reader;
-        return (reader.parse(json, to) &&
+        return reader.parse(json, to) &&
-               !to.isNull() &&
+                bool (to) &&
-                to.isObject());
+                to.isObject();
     }
 
     void testParseJSONArrayWithInvalidChildrenObjects ()

src/ripple/rpc/handlers/AccountCurrencies.cpp

@@ -61,7 +61,7 @@ Json::Value doAccountCurrencies (RPC::Context& context)
     Json::Value jvAccepted (
         RPC::accountFromString (accountID, bIndex, strIdent, iIndex, bStrict));
 
-    if (!jvAccepted.empty ())
+    if (jvAccepted)
         return jvAccepted;
 
     std::set<Currency> send, receive;

src/ripple/rpc/handlers/AccountInfo.cpp

@@ -60,7 +60,7 @@ Json::Value doAccountInfo (RPC::Context& context)
     auto jvAccepted = RPC::accountFromString (
         accountID, bIndex, strIdent, iIndex, bStrict);
 
-    if (!jvAccepted.empty ())
+    if (jvAccepted)
         return jvAccepted;
 
     auto const sleAccepted = cachedRead(*ledger,

src/ripple/rpc/handlers/AccountLines.cpp

@@ -95,7 +95,7 @@ Json::Value doAccountLines (RPC::Context& context)
 
     auto jv = RPC::accountFromString (
         accountID, bIndex, strIdent, iIndex, false);
-    if (! jv.empty ())
+    if (jv)
     {
         for (auto it = jv.begin (); it != jv.end (); ++it)
             result[it.memberName ()] = it.key ();
@@ -125,7 +125,7 @@ Json::Value doAccountLines (RPC::Context& context)
         result = RPC::accountFromString (
             raPeerAccount, bPeerIndex, strPeer, iPeerIndex, false);
 
-        if (! result.empty ())
+        if (result)
             return result;
     }
 

src/ripple/rpc/handlers/AccountObjects.cpp

@@ -60,7 +60,7 @@ Json::Value doAccountObjects (RPC::Context& context)
             ? context.params[jss::account_index].asUInt () : 0;
         auto jv = RPC::accountFromString (
             accountID, bIndex, strIdent, iIndex, false);
-        if (! jv.empty ())
+        if (jv)
         {
             for (auto it = jv.begin (); it != jv.end (); ++it)
                 result[it.memberName ()] = it.key ();

src/ripple/rpc/handlers/AccountOffers.cpp

@@ -50,7 +50,7 @@ Json::Value doAccountOffers (RPC::Context& context)
 
     Json::Value const jv = RPC::accountFromString (
         accountID, bIndex, strIdent, iIndex, false);
-    if (! jv.empty ())
+    if (jv)
     {
         for (Json::Value::const_iterator it (jv.begin ()); it != jv.end (); ++it)
             result[it.memberName ()] = it.key ();

src/ripple/rpc/handlers/AccountTx.cpp

@@ -162,7 +162,7 @@ Json::Value doAccountTx (RPC::Context& context)
         ret[jss::ledger_index_max] = uLedgerMax;
         if (params.isMember (jss::limit))
             ret[jss::limit]        = limit;
-        if (!resumeToken.isNull())
+        if (resumeToken)
             ret[jss::marker] = resumeToken;
 
         return ret;

src/ripple/rpc/handlers/GatewayBalances.cpp

@@ -82,7 +82,7 @@ Json::Value doGatewayBalances (RPC::Context& context)
     Json::Value jvAccepted = RPC::accountFromString (
         accountID, bIndex, strIdent, iIndex, bStrict);
 
-    if (!jvAccepted.empty ())
+    if (jvAccepted)
         return jvAccepted;
 
     context.loadType = Resource::feeHighBurdenRPC;

src/ripple/rpc/handlers/NoRippleCheck.cpp

@@ -100,7 +100,7 @@ Json::Value doNoRippleCheck (RPC::Context& context)
 
     Json::Value const jv = RPC::accountFromString (
         accountID, bIndex, strIdent, iIndex, false);
-    if (! jv.empty ())
+    if (jv)
     {
         for (Json::Value::const_iterator it (jv.begin ()); it != jv.end (); ++it)
             result[it.memberName ()] = it.key ();

src/ripple/rpc/handlers/OwnerInfo.cpp

@@ -52,7 +52,7 @@ Json::Value doOwnerInfo (RPC::Context& context)
         iIndex,
         false);
 
-    ret[jss::accepted] = jAccepted.empty () ?
+    ret[jss::accepted] = ! jAccepted ?
             context.netOps.getOwnerInfo (closedLedger, accountID) : jAccepted;
 
     auto const& currentLedger = context.netOps.getCurrentLedger ();
@@ -63,9 +63,8 @@ Json::Value doOwnerInfo (RPC::Context& context)
         iIndex,
         false);
 
-    ret[jss::current] = jCurrent.empty () ?
+    ret[jss::current] = ! jCurrent ?
             context.netOps.getOwnerInfo (currentLedger, accountID) : jCurrent;
-
     return ret;
 }
 

src/ripple/rpc/impl/LookupLedger.cpp

@@ -48,7 +48,7 @@ Status ledgerFromRequest (
 
     // We need to support the legacy "ledger" field.
     auto& legacyLedger = params[jss::ledger];
-    if (!legacyLedger.empty())
+    if (legacyLedger)
     {
         if (legacyLedger.asString().size () > 12)
             hashValue = legacyLedger;
@@ -56,7 +56,7 @@ Status ledgerFromRequest (
             indexValue = legacyLedger;
     }
 
-    if (!hashValue.empty())
+    if (hashValue)
     {
         if (! hashValue.isString ())
             return {rpcINVALID_PARAMS, "ledgerHashNotString"};

src/ripple/rpc/tests/Status.test.cpp

@@ -107,19 +107,19 @@ private:
     {
         testcase ("OK");
         fillJson (Status ());
-        expect (value_.empty(), "Value for empty status");
+        expect (! value_, "Value for empty status");
 
         fillJson (0);
-        expect (value_.empty(), "Value for 0 status");
+        expect (! value_, "Value for 0 status");
 
         fillJson (Status::OK);
-        expect (value_.empty(), "Value for OK status");
+        expect (! value_, "Value for OK status");
 
         fillJson (tesSUCCESS);
-        expect (value_.empty(), "Value for tesSUCCESS");
+        expect (! value_, "Value for tesSUCCESS");
 
         fillJson (rpcSUCCESS);
-        expect (value_.empty(), "Value for rpcSUCCESS");
+        expect (! value_, "Value for rpcSUCCESS");
     }
 
     template <typename Type>
@@ -133,10 +133,10 @@ private:
         fillJson (Status (status, messages));
 
         auto prefix = label + ": ";
-        expect (!value_.empty(), prefix + "No value");
+        expect (bool (value_), prefix + "No value");
 
         auto error = value_[jss::error];
-        expect (!error.empty(), prefix + "No error.");
+        expect (bool (error), prefix + "No error.");
 
         auto code = error[jss::code].asInt();
         expect (status == code, prefix + "Wrong status " +

src/ripple/server/impl/ServerHandlerImp.cpp

@@ -242,7 +242,7 @@ ServerHandlerImp::processRequest (
         Json::Reader reader;
         if ((request.size () > 1000000) ||
             ! reader.parse (request, jsonRPC) ||
-            jsonRPC.isNull () ||
+            ! jsonRPC ||
             ! jsonRPC.isObject ())
         {
             HTTPReply (400, "Unable to parse request", output);
@@ -258,7 +258,7 @@ ServerHandlerImp::processRequest (
 
     Json::Value const& method = jsonRPC ["method"];
 
-    if (method.isNull ()) {
+    if (! method) {
         HTTPReply (400, "Null method", output);
         return;
     }
@@ -313,7 +313,7 @@ ServerHandlerImp::processRequest (
     // and we take that first entry and validate that it's an object.
     Json::Value params = jsonRPC [jss::params];
 
-    if (params.isNull () || params.empty())
+    if (! params)
         params = Json::Value (Json::objectValue);
 
     else if (!params.isArray () || params.size() != 1)

src/ripple/websocket/Handler.h

@@ -403,7 +403,7 @@ public:
             send (cpClient, jvResult, false);
         }
         else if (!jrReader.parse (mpMessage->get_payload (), jvRequest) ||
-                 jvRequest.isNull () || !jvRequest.isObject ())
+                 ! jvRequest || !jvRequest.isObject ())
         {
             Json::Value jvResult (Json::objectValue);