Pairwise no ripple:

* Cannot set noRipple flag with negative balance.
* Paths with consecutive no ripple links are invalid
* Adjust pathfinding value of no ripple out paths
* Check for no ripple when adding links in pathfinding
* Remove old noRipple logic
* Update trust line delete logic

src/ripple_data/protocol/SerializedTypes.h

@@ -592,6 +592,10 @@ public:
     {
         return !mIsNegative && !isZero ();
     }
+    bool isLEZero () const
+    {
+        return mIsNegative || isZero ();
+    }
     bool isGEZero () const
     {
         return !mIsNegative;

src/ripple_data/protocol/TER.cpp

@@ -108,6 +108,7 @@ bool transResultInfo (TER terCode, std::string& strToken, std::string& strHuman)
         {   terFUNDS_SPENT,         "terFUNDS_SPENT",           "Can't set password, password set funds already spent." },
         {   terINSUF_FEE_B,         "terINSUF_FEE_B",           "Account balance can't pay fee."                        },
         {   terLAST,                "terLAST",                  "Process last."                                         },
+        {   terNO_RIPPLE,           "terNO_RIPPLE",             "Path does not permit rippling."                        },
         {   terNO_ACCOUNT,          "terNO_ACCOUNT",            "The source account does not exist."                    },
         {   terNO_AUTH,             "terNO_AUTH",               "Not authorized to hold IOUs."                          },
         {   terNO_LINE,             "terNO_LINE",               "No such line."                                         },

src/ripple_data/protocol/TER.h

@@ -128,6 +128,7 @@ enum TER    // aka TransactionEngineResult
     terOWNERS,              // Can't succeed with non-zero owner count.
     terPRE_SEQ,             // Can't pay fee, no point in forwarding, therefore don't burden network.
     terLAST,                // Process after all other transactions
+    terNO_RIPPLE,           // Rippling not allowed
 
     // 0: S Success (success)
     // Causes: