make class more compatible with std::vector

2 files changed, 72 insertions, 5 deletions

diff --git a/library/cpp/containers/compact_vector/compact_vector.h b/library/cpp/containers/compact_vector/compact_vector.h
index b3795708a5..b31a8b8464 100644
--- a/library/cpp/containers/compact_vector/compact_vector.h
+++ b/library/cpp/containers/compact_vector/compact_vector.h
@@ -31,12 +31,21 @@ private:
         return ((THeader*)Ptr) - 1;
     }
 
+    void destruct_at(size_t pos) {
+        (*this)[pos].~T();
+    }
+
 public:
-    typedef T* TIterator;
-    typedef const T* TConstIterator;
+    using value_type = T;
+
+    using TIterator = T*;
+    using TConstIterator = const T*;
+
+    using iterator = TIterator ;
+    using const_iterator = TConstIterator;
 
-    typedef TIterator iterator;
-    typedef TConstIterator const_iterator;
+    using reverse_iterator = std::reverse_iterator<iterator>;
+    using const_reverse_iterator = std::reverse_iterator<const_iterator>;
 
     TCompactVector()
         : Ptr(nullptr)
@@ -81,7 +90,7 @@ public:
     ~TCompactVector() {
         for (size_t i = 0; i < Size(); ++i) {
             try {
-                (*this)[i].~T();
+                destruct_at(i);
             } catch (...) {
             }
         }
@@ -132,6 +141,22 @@ public:
         return End();
     }
 
+    reverse_iterator rbegin() {
+        return std::make_reverse_iterator(end());
+    }
+
+    const_reverse_iterator rbegin() const {
+        return std::make_reverse_iterator(end());
+    }
+
+    reverse_iterator rend() {
+        return std::make_reverse_iterator(begin());
+    }
+
+    const_reverse_iterator rend() const {
+        return std::make_reverse_iterator(begin());
+    }
+
     void Swap(TThis& that) noexcept {
         DoSwap(Ptr, that.Ptr);
     }
@@ -166,6 +191,10 @@ public:
         }
     }
 
+    void reserve(size_t newCapacity) {
+        Reserve(newCapacity);
+    }
+
     size_t Size() const {
         return Ptr ? Header()->Size : 0;
     }
@@ -248,6 +277,13 @@ public:
         Clear();
     }
 
+    void erase(iterator position) {
+        Y_ENSURE(position >= begin() && position < end());
+        std::move(position + 1, end(), position);
+        destruct_at(Size() - 1);
+        Header()->Size -= 1;
+    }
+
     T& operator[](size_t index) {
         Y_ASSERT(index < Size());
         return Ptr[index];
diff --git a/library/cpp/containers/compact_vector/compact_vector_ut.cpp b/library/cpp/containers/compact_vector/compact_vector_ut.cpp
index 84cb7b645a..ed2936fb9e 100644
--- a/library/cpp/containers/compact_vector/compact_vector_ut.cpp
+++ b/library/cpp/containers/compact_vector/compact_vector_ut.cpp
@@ -94,4 +94,35 @@ Y_UNIT_TEST_SUITE(TCompactVectorTest) {
         UNIT_ASSERT_VALUES_EQUAL(3u, vector2[3]);
         UNIT_ASSERT_VALUES_EQUAL(5u, vector2[4]);
     }
+
+    Y_UNIT_TEST(TestReverseIterators) {
+        TCompactVector<std::string> vector = {
+                "мама",
+                "мыла",
+                "раму"
+        };
+
+        TCompactVector<std::string> reverseVector(vector.rbegin(), vector.rend());
+        UNIT_ASSERT_VALUES_EQUAL(3u, reverseVector.Size());
+
+        UNIT_ASSERT_VALUES_EQUAL("раму", reverseVector[0]);
+        UNIT_ASSERT_VALUES_EQUAL("мыла", reverseVector[1]);
+        UNIT_ASSERT_VALUES_EQUAL("мама", reverseVector[2]);
+    }
+
+    Y_UNIT_TEST(TestErase) {
+        TCompactVector<std::string> vector = {
+                "мама",
+                "утром",
+                "мыла",
+                "раму"
+        };
+
+        vector.erase(vector.begin() + 1);
+        UNIT_ASSERT_VALUES_EQUAL(3u, vector.Size());
+
+        UNIT_ASSERT_VALUES_EQUAL("мама", vector[0]);
+        UNIT_ASSERT_VALUES_EQUAL("мыла", vector[1]);
+        UNIT_ASSERT_VALUES_EQUAL("раму", vector[2]);
+    }
 }