intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 96 insertions, 0 deletions

diff --git a/library/cpp/protobuf/util/repeated_field_utils.h b/library/cpp/protobuf/util/repeated_field_utils.h
new file mode 100644
index 0000000000..c07bd84647
--- /dev/null
+++ b/library/cpp/protobuf/util/repeated_field_utils.h
@@ -0,0 +1,96 @@
+#pragma once
+
+#include <google/protobuf/repeated_field.h>
+#include <util/generic/vector.h>
+
+template <typename T>
+void RemoveRepeatedPtrFieldElement(google::protobuf::RepeatedPtrField<T>* repeated, unsigned index) {
+    google::protobuf::RepeatedPtrField<T> r;
+    Y_ASSERT(index < (unsigned)repeated->size());
+    for (unsigned i = 0; i < (unsigned)repeated->size(); ++i) {
+        if (i == index) {
+            continue;
+        }
+        r.Add()->Swap(repeated->Mutable(i));
+    }
+    r.Swap(repeated);
+}
+
+namespace NProtoBuf {
+    /// Move item to specified position
+    template <typename TRepeated>
+    static void MoveRepeatedFieldItem(TRepeated* field, size_t indexFrom, size_t indexTo) {
+        if (!field->size() || indexFrom >= static_cast<size_t>(field->size()) || indexFrom == indexTo)
+            return;
+        if (indexTo >= static_cast<size_t>(field->size()))
+            indexTo = field->size() - 1;
+        if (indexFrom > indexTo) {
+            for (size_t i = indexFrom; i > indexTo; --i)
+                field->SwapElements(i, i - 1);
+        } else {
+            for (size_t i = indexFrom; i < indexTo; ++i)
+                field->SwapElements(i, i + 1);
+        }
+    }
+
+    template <typename T>
+    static T* InsertRepeatedFieldItem(NProtoBuf::RepeatedPtrField<T>* field, size_t index) {
+        T* ret = field->Add();
+        MoveRepeatedFieldItem(field, field->size() - 1, index);
+        return ret;
+    }
+
+    template <typename TRepeated> // suitable both for RepeatedField and RepeatedPtrField
+    static void RemoveRepeatedFieldItem(TRepeated* field, size_t index) {
+        if ((int)index >= field->size())
+            return;
+
+        for (int i = index + 1; i < field->size(); ++i)
+            field->SwapElements(i - 1, i);
+
+        field->RemoveLast();
+    }
+
+    template <typename TRepeated, typename TPred> // suitable both for RepeatedField and RepeatedPtrField
+    static void RemoveRepeatedFieldItemIf(TRepeated* repeated, TPred p) {
+        auto last = std::remove_if(repeated->begin(), repeated->end(), p);
+        if (last != repeated->end()) {
+            size_t countToRemove = repeated->end() - last;
+            while (countToRemove--)
+                repeated->RemoveLast();
+        }
+    }
+
+    namespace NImpl {
+        template <typename TRepeated>
+        static void ShiftLeft(TRepeated* field, int begIndex, int endIndex, size_t shiftSize) {
+            Y_ASSERT(begIndex <= field->size());
+            Y_ASSERT(endIndex <= field->size());
+            size_t shiftIndex = (int)shiftSize < begIndex ? begIndex - shiftSize : 0;
+            for (int i = begIndex; i < endIndex; ++i, ++shiftIndex)
+                field->SwapElements(shiftIndex, i);
+        }
+    }
+
+    // Remove several items at once, could be more efficient compared to calling RemoveRepeatedFieldItem several times
+    template <typename TRepeated>
+    static void RemoveRepeatedFieldItems(TRepeated* field, const TVector<size_t>& sortedIndices) {
+        if (sortedIndices.empty())
+            return;
+
+        size_t shift = 1;
+        for (size_t i = 1; i < sortedIndices.size(); ++i, ++shift)
+            NImpl::ShiftLeft(field, sortedIndices[i - 1] + 1, sortedIndices[i], shift);
+        NImpl::ShiftLeft(field, sortedIndices.back() + 1, field->size(), shift);
+
+        for (; shift > 0; --shift)
+            field->RemoveLast();
+    }
+
+    template <typename TRepeated>
+    static void ReverseRepeatedFieldItems(TRepeated* field) {
+        for (int i1 = 0, i2 = field->size() - 1; i1 < i2; ++i1, --i2)
+            field->SwapElements(i1, i2);
+    }
+
+}