Use Utils::setUnionMerge

And fix some details of the implementations.

Change-Id: I8e77fee4b95658a69ef1656bb406811de091ce16
Reviewed-by: Ivan Donchevskii <ivan.donchevskii@qt.io>

3 files changed, 15 insertions, 95 deletions

diff --git a/src/libs/utils/algorithm.h b/src/libs/utils/algorithm.h
index 97fc1f626b..9b699fee1c 100644
--- a/src/libs/utils/algorithm.h
+++ b/src/libs/utils/algorithm.h
@@ -42,6 +42,7 @@
 #include <QStringList>
 
 #include <memory>
+#include <type_traits>
 
 namespace Utils
 {
@@ -808,7 +809,7 @@ OutputIt setUnionMerge(InputIt1 first1,
                          last2,
                          d_first,
                          merge,
-                         std::less<decltype(*first1)>{});
+                         std::less<std::decay_t<decltype(*first1)>>{});
 }
 
 template<class OutputContainer,
@@ -843,9 +844,9 @@ OutputContainer setUnionMerge(InputContainer1 &&input1,
                               InputContainer2 &&input2,
                               Merge merge)
 {
-    return setUnionMerge(std::forward<InputContainer1>(input1),
-                         std::forward<InputContainer2>(input2),
-                         merge,
-                         std::less<decltype(*std::begin(input1))>{});
+    return setUnionMerge<OutputContainer>(std::forward<InputContainer1>(input1),
+                                          std::forward<InputContainer2>(input2),
+                                          merge,
+                                          std::less<std::decay_t<decltype(*std::begin(input1))>>{});
 }
 } // namespace Utils
diff --git a/src/tools/clangrefactoringbackend/source/projectpartqueue.cpp b/src/tools/clangrefactoringbackend/source/projectpartqueue.cpp
index d1fdc5a83d..d64714310b 100644
--- a/src/tools/clangrefactoringbackend/source/projectpartqueue.cpp
+++ b/src/tools/clangrefactoringbackend/source/projectpartqueue.cpp
@@ -23,6 +23,8 @@
 **
 ****************************************************************************/
 
+#include <utils/algorithm.h>
+
 #include "projectpartqueue.h"
 
 namespace ClangBackEnd {
@@ -32,41 +34,6 @@ ProjectPartQueue::ProjectPartQueue()
 
 }
 
-namespace {
-
-template<class InputIt1,
-         class InputIt2,
-         class OutputIt,
-         class Compare,
-         class Merge>
-OutputIt set_union_merge(InputIt1 first1,
-                         InputIt1 last1,
-                         InputIt2 first2,
-                         InputIt2 last2,
-                         OutputIt d_first,
-                         Compare comp,
-                         Merge merge)
-{
-    for (; first1 != last1; ++d_first) {
-        if (first2 == last2)
-            return std::copy(first1, last1, d_first);
-        if (comp(*first2, *first1)) {
-            *d_first = *first2++;
-        } else {
-            if (comp(*first1, *first2)) {
-                *d_first = *first1;
-            } else {
-                *d_first = merge(*first1, *first2);
-                ++first2;
-            }
-            ++first1;
-        }
-    }
-    return std::copy(first2, last2, d_first);
-}
-
-}
-
 void ProjectPartQueue::addProjectParts(V2::ProjectPartContainers &&projectParts)
 {
     auto compare = [](const V2::ProjectPartContainer &first, const V2::ProjectPartContainer &second) {
@@ -98,17 +65,10 @@ void ProjectPartQueue::addProjectParts(V2::ProjectPartContainers &&projectParts)
         return first;
     };
 
-    V2::ProjectPartContainers mergedProjectParts;
-    mergedProjectParts.reserve(m_projectParts.size() + projectParts.size());
-    set_union_merge(std::make_move_iterator(m_projectParts.begin()),
-                    std::make_move_iterator(m_projectParts.end()),
-                    std::make_move_iterator(projectParts.begin()),
-                    std::make_move_iterator(projectParts.end()),
-                    std::back_inserter(mergedProjectParts),
-                    compare,
-                    merge);
-
-    m_projectParts = std::move(mergedProjectParts);
+    m_projectParts = Utils::setUnionMerge<V2::ProjectPartContainers>(m_projectParts,
+                                                                     projectParts,
+                                                                     merge,
+                                                                     compare);
 }
 
 class CompareDifference
diff --git a/src/tools/clangrefactoringbackend/source/symbolindexertaskqueue.cpp b/src/tools/clangrefactoringbackend/source/symbolindexertaskqueue.cpp
index 4bfed1fe31..3f02ca0ade 100644
--- a/src/tools/clangrefactoringbackend/source/symbolindexertaskqueue.cpp
+++ b/src/tools/clangrefactoringbackend/source/symbolindexertaskqueue.cpp
@@ -27,60 +27,19 @@
 
 #include <symbolindexertaskschedulerinterface.h>
 
-namespace ClangBackEnd {
-
-namespace {
-
-template<class InputIt1,
-         class InputIt2,
-         class OutputIt,
-         class Merge>
-OutputIt set_union_merge(InputIt1 first1,
-                         InputIt1 last1,
-                         InputIt2 first2,
-                         InputIt2 last2,
-                         OutputIt d_first,
-                         Merge merge)
-{
-    for (; first1 != last1; ++d_first) {
-        if (first2 == last2)
-            return std::copy(first1, last1, d_first);
-        if (*first2 < *first1) {
-            *d_first = *first2++;
-        } else {
-            if (*first1 < *first2) {
-                *d_first = *first1;
-            } else {
-                *d_first = merge(*first1, *first2);
-                ++first2;
-            }
-            ++first1;
-        }
-    }
-    return std::copy(first2, last2, d_first);
-}
+#include <utils/algorithm.h>
 
-}
+namespace ClangBackEnd {
 
 void SymbolIndexerTaskQueue::addOrUpdateTasks(std::vector<SymbolIndexerTask> &&tasks)
 {
-    std::vector<SymbolIndexerTask> mergedTasks;
-    mergedTasks.reserve(m_tasks.size() + tasks.size());
-
     auto merge = [] (SymbolIndexerTask &&first, SymbolIndexerTask &&second) {
         first.callable = std::move(second.callable);
 
         return std::move(first);
     };
 
-    set_union_merge(std::make_move_iterator(tasks.begin()),
-                    std::make_move_iterator(tasks.end()),
-                    std::make_move_iterator(m_tasks.begin()),
-                    std::make_move_iterator(m_tasks.end()),
-                    std::back_inserter(mergedTasks),
-                    merge);
-
-    m_tasks = std::move(mergedTasks);
+    m_tasks = Utils::setUnionMerge<std::vector<SymbolIndexerTask>>(tasks, m_tasks, merge);
 }
 
 void SymbolIndexerTaskQueue::removeTasks(const Utils::SmallStringVector &projectPartIds)