From 0a3e1af04c804af94568a0a85d6afce7a39a24e9 Mon Sep 17 00:00:00 2001
From: JoelKatz <DavidJoelSchwartz@GMail.com>
Date: Tue, 28 Oct 2014 11:34:27 -0700
Subject: [PATCH] When pathfinding, don't output a redundant account node

---
 src/ripple/app/paths/Pathfinder.cpp | 37 +++++++++++++++++++----------
 src/ripple/protocol/STPathSet.h     | 10 ++++++++
 2 files changed, 34 insertions(+), 13 deletions(-)

diff --git a/src/ripple/app/paths/Pathfinder.cpp b/src/ripple/app/paths/Pathfinder.cpp
index a912c44a3c..55495a10e8 100644
--- a/src/ripple/app/paths/Pathfinder.cpp
+++ b/src/ripple/app/paths/Pathfinder.cpp
@@ -1086,20 +1086,31 @@ void Pathfinder::addLink (
                         book->getIssuerOut (),
                         book->getCurrencyOut (),
                         book->getIssuerOut ()))
-                    { // Don't want the book if we've already seen the issuer
-                        // add the order book itself
-                        newPath.emplace_back (
-                            STPathElement::typeCurrency |
-                            STPathElement::typeIssuer,
-                            xrpAccount (),
-                            book->getCurrencyOut (),
-                            book->getIssuerOut ());
-
-                        if (book->getIssuerOut () == mDstAccount &&
-                            book->getCurrencyOut () == mDstAmount.getCurrency())
+                    {
+                        // Don't want the book if we've already seen the issuer
+                        // book -> account -> book
+                        if ((newPath.size() >= 2) &&
+                            (newPath.back().isAccount ()) &&
+                            (newPath[newPath.size() - 2].isOffer ()))
                         {
-                            // with the destination account, this path is
-                            // complete
+                            // replace the redundant account with the order book
+                            newPath[newPath.size() - 1] = STPathElement (
+                                STPathElement::typeCurrency | STPathElement::typeIssuer,
+                                xrpAccount(), book->getCurrencyOut(),
+                                book->getIssuerOut());
+                        }
+                        else
+                        {
+                            // add the order book
+                            newPath.emplace_back(
+                                STPathElement::typeCurrency | STPathElement::typeIssuer,
+                                xrpAccount(), book->getCurrencyOut(),
+                                book->getIssuerOut());
+                        }
+
+                        if (book->getIssuerOut() == mDstAccount &&
+                            book->getCurrencyOut() == mDstAmount.getCurrency())
+                        { // with the destination account, this path is complete
                             WriteLog (lsTRACE, Pathfinder)
                                 << "complete path found ba: "
                                 << currentPath.getJson(0);
diff --git a/src/ripple/protocol/STPathSet.h b/src/ripple/protocol/STPathSet.h
index 931eeef187..f5acfe1eca 100644
--- a/src/ripple/protocol/STPathSet.h
+++ b/src/ripple/protocol/STPathSet.h
@@ -195,6 +195,16 @@ public:
         return mPath.front ();
     }
 
+    STPathElement& operator[](int i)
+    {
+        return mPath[i];
+    }
+
+    const STPathElement& operator[](int i) const
+    {
+        return mPath[i];
+    }
+
 private:
     std::vector<STPathElement> mPath;
 };