Remove dependency on boost::filter_iterator

By implementing our own filter iterator.

Author: joto

.github/actions/install-windows/action.yml

@@ -4,6 +4,6 @@ runs:
   using: composite
   steps:
     - name: Install packages
-      run: vcpkg install bzip2:x64-windows expat:x64-windows zlib:x64-windows boost-crc:x64-windows boost-iterator:x64-windows boost-variant:x64-windows sparsehash:x64-windows
+      run: vcpkg install bzip2:x64-windows expat:x64-windows zlib:x64-windows boost-crc:x64-windows boost-variant:x64-windows sparsehash:x64-windows
       shell: bash
 

include/osmium/memory/collection.hpp

@@ -113,6 +113,70 @@ namespace osmium {
             return out;
         }
 
+        template <typename TFilter, typename TMember>
+        class CollectionFilterIterator {
+
+            TFilter m_filter;
+            CollectionIterator<TMember> m_it;
+            CollectionIterator<TMember> m_end;
+
+            void advance() {
+                while (m_it != m_end) {
+                    if (m_filter(*m_it)) {
+                        break;
+                    }
+                    ++m_it;
+                }
+            }
+
+        public:
+
+            using iterator_category = std::forward_iterator_tag;
+            using value_type        = const TMember;
+            using difference_type   = std::ptrdiff_t;
+            using pointer           = value_type*;
+            using reference         = value_type&;
+
+            CollectionFilterIterator(const TFilter& filter, CollectionIterator<TMember> begin, CollectionIterator<TMember> end) :
+                m_filter(filter),
+                m_it(begin),
+                m_end(end) {
+                advance();
+            }
+
+            CollectionFilterIterator& operator++() {
+                assert(m_it != m_end);
+                ++m_it;
+                advance();
+                return *this;
+            }
+
+            CollectionFilterIterator operator++(int) const {
+                CollectionFilterIterator tmp{*this};
+                operator++();
+                return tmp;
+            }
+
+            bool operator==(const CollectionFilterIterator& rhs) const noexcept {
+                return m_it == rhs.m_it && m_end == rhs.m_end;
+            }
+
+            bool operator!=(const CollectionFilterIterator& rhs) const noexcept {
+                return !(*this == rhs);
+            }
+
+            reference operator*() const noexcept {
+                assert(m_it != m_end);
+                return *m_it;
+            }
+
+            pointer operator->() const noexcept {
+                assert(m_it != m_end);
+                return &*m_it;
+            }
+
+        }; // class CollectionFilterIterator
+
         template <typename TMember, osmium::item_type TCollectionItemType>
         class Collection : public Item {
 

include/osmium/tags/filter.hpp

@@ -36,8 +36,6 @@ DEALINGS IN THE SOFTWARE.
 #include <osmium/memory/collection.hpp>
 #include <osmium/osm/tag.hpp>
 
-#include <boost/iterator/filter_iterator.hpp>
-
 #include <cstddef>
 #include <cstring>
 #include <string>
@@ -126,7 +124,7 @@ namespace osmium {
             using filter_type   = Filter<TKey, TValue, TKeyComp, TValueComp>;
             using argument_type = const osmium::Tag&;
             using result_type   = bool;
-            using iterator      = boost::filter_iterator<filter_type, osmium::TagList::const_iterator>;
+            using iterator      = osmium::memory::CollectionFilterIterator<filter_type, const osmium::Tag>;
 
             explicit Filter(bool default_result = false) :
                 m_default_result(default_result) {

include/osmium/tags/tags_filter.hpp

@@ -36,8 +36,6 @@ DEALINGS IN THE SOFTWARE.
 #include <osmium/osm/tag.hpp>
 #include <osmium/tags/matcher.hpp>
 
-#include <boost/iterator/filter_iterator.hpp>
-
 #include <utility>
 #include <vector>
 
@@ -72,7 +70,7 @@ namespace osmium {
 
     public:
 
-        using iterator = boost::filter_iterator<TagsFilterBase, osmium::TagList::const_iterator>;
+        using iterator = osmium::memory::CollectionFilterIterator<TagsFilterBase, const osmium::Tag>;
 
         /**
          * Constructor.