[Bf-blender-cvs] [b166e18d56e] functions: small vector - remove and reorder

[Jacques Lucke]

Commit: b166e18d56e242d3da81616ceb28c4477483f7b4
Author: Jacques Lucke
Date:   Sun Feb 17 15:49:43 2019 +0100
Branches: functions
https://developer.blender.org/rBb166e18d56e242d3da81616ceb28c4477483f7b4

small vector - remove and reorder

===================================================================

M	source/blender/blenlib/BLI_small_vector.hpp
M	tests/gtests/blenlib/BLI_small_vector_test.cc

===================================================================

diff --git a/source/blender/blenlib/BLI_small_vector.hpp b/source/blender/blenlib/BLI_small_vector.hpp
index ca5cb47b6d7..8ed42027e4a 100644
--- a/source/blender/blenlib/BLI_small_vector.hpp
+++ b/source/blender/blenlib/BLI_small_vector.hpp
@@ -119,7 +119,21 @@ namespace BLI {
 		void remove_last()
 		{
 			BLI_assert(!this->empty());
-			(this->m_elements + m_size - 1)->~T();
+			this->destruct_element(m_size - 1);
+			m_size--;
+		}
+
+		void remove_and_reorder(uint index)
+		{
+			BLI_assert(this->is_index_in_range(index));
+			if (index < m_size - 1) {
+				/* Move last element to index. */
+				std::copy(
+					std::make_move_iterator(this->end() - 1),
+					std::make_move_iterator(this->end()),
+					this->element_ptr(index));
+			}
+			this->destruct_element(m_size - 1);
 			m_size--;
 		}
 
@@ -135,7 +149,7 @@ namespace BLI {
 
 		T &operator[](const int index) const
 		{
-			BLI_assert(index >= 0 && index < this->size());
+			BLI_assert(this->is_index_in_range(index));
 			return m_elements[index];
 		}
 
@@ -168,6 +182,16 @@ namespace BLI {
 			return m_elements == this->small_buffer();
 		}
 
+		bool is_index_in_range(uint index) const
+		{
+			return index >= 0 && index < this->size();
+		}
+
+		T *element_ptr(uint index) const
+		{
+			return m_elements + index;
+		}
+
 		inline void ensure_space_for_one()
 		{
 			if (m_size >= m_capacity) {
@@ -245,10 +269,14 @@ namespace BLI {
 		void destruct_elements_but_keep_memory()
 		{
 			for (uint i = 0; i < m_size; i++) {
-				(m_elements + i)->~T();
+				this->destruct_element(i);
 			}
 		}
 
+		void destruct_element(uint index)
+		{
+			this->element_ptr(index)->~T();
+		}
 	};
 
 } /* namespace BLI */
\ No newline at end of file
diff --git a/tests/gtests/blenlib/BLI_small_vector_test.cc b/tests/gtests/blenlib/BLI_small_vector_test.cc
index 1e781cb4ae4..2311552e080 100644
--- a/tests/gtests/blenlib/BLI_small_vector_test.cc
+++ b/tests/gtests/blenlib/BLI_small_vector_test.cc
@@ -175,4 +175,20 @@ TEST(small_vector, Empty)
 	EXPECT_FALSE(vec.empty());
 	vec.remove_last();
 	EXPECT_TRUE(vec.empty());
+}
+
+TEST(small_vector, RemoveReorder)
+{
+	IntVector vec = {4, 5, 6, 7};
+	vec.remove_and_reorder(1);
+	EXPECT_EQ(vec[0], 4);
+	EXPECT_EQ(vec[1], 7);
+	EXPECT_EQ(vec[2], 6);
+	vec.remove_and_reorder(2);
+	EXPECT_EQ(vec[0], 4);
+	EXPECT_EQ(vec[1], 7);
+	vec.remove_and_reorder(0);
+	EXPECT_EQ(vec[0], 7);
+	vec.remove_and_reorder(0);
+	EXPECT_TRUE(vec.empty());
 }
\ No newline at end of file