From 3397b8f14fa649f8907bd7b2974f1b5792cf99ef Mon Sep 17 00:00:00 2001
From: artemp <artem@mapnik.org>
Date: Thu, 14 Jul 2016 09:46:37 +0100
Subject: [PATCH] feature_kv_iterator - change logic in 'increment' to skip
 key/value's when value doesn't exist

---
 include/mapnik/feature_kv_iterator.hpp | 2 +-
 src/feature_kv_iterator.cpp            | 8 ++++++--
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/include/mapnik/feature_kv_iterator.hpp b/include/mapnik/feature_kv_iterator.hpp
index 77b292fd5..3abe37131 100644
--- a/include/mapnik/feature_kv_iterator.hpp
+++ b/include/mapnik/feature_kv_iterator.hpp
@@ -46,7 +46,7 @@ class feature_impl;
 
 class MAPNIK_DECL feature_kv_iterator :
         public boost::iterator_facade<feature_kv_iterator,
-                                      std::tuple<std::string , value> const,
+                                      std::tuple<std::string, value> const,
                                       boost::forward_traversal_tag>
 {
 public:
diff --git a/src/feature_kv_iterator.cpp b/src/feature_kv_iterator.cpp
index 4ae384254..241908ab6 100644
--- a/src/feature_kv_iterator.cpp
+++ b/src/feature_kv_iterator.cpp
@@ -39,16 +39,20 @@ feature_kv_iterator::feature_kv_iterator (feature_impl const& f, bool begin)
 void feature_kv_iterator::increment()
 {
     ++itr_;
+    for ( ;itr_ != f_.ctx_->end(); ++itr_)
+    {
+        if (f_.has_key(itr_->first)) break;
+    }
 }
 
 void feature_kv_iterator::decrement()
 {
-    // dummy //--itr_;
+    // no-op //--itr_;
 }
 
 void feature_kv_iterator::advance(boost::iterator_difference<feature_kv_iterator>::type )
 {
-    // dummy
+    // no-op
 }
 
 bool feature_kv_iterator::equal( feature_kv_iterator const& other) const