Add support for Clear() method

closes #30
joaoportela · Feb 3, 2022 · 5b1991b · 5b1991b
1 parent 8773cab
commit 5b1991b
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Showing 3 changed files with 48 additions and 4 deletions.
diff --git a/CircularBuffer.Example/Program.cs b/CircularBuffer.Example/Program.cs
@@ -35,14 +35,15 @@ static void Main(string[] args)
             }
             Console.WriteLine("\nbuffer.PushFront() {2,1,0} respectively:");
             PrintBuffer(buffer);
+
+            buffer.Clear();
+            Console.WriteLine("\nbuffer.Clear():");
+            PrintBuffer(buffer);
         }
 
         private static void PrintBuffer(CircularBuffer<int> buffer)
         {
-            for (int i = 0; i < buffer.Size; i++)
-            {
-                Console.WriteLine($"buffer[{i}] = {buffer[i]}");
-            }
+            Console.WriteLine($"{{{String.Join(",", buffer.ToArray())}}}");
         }
     }
 }
diff --git a/CircularBuffer.Tests/CircularBufferTests.cs b/CircularBuffer.Tests/CircularBufferTests.cs
@@ -291,5 +291,35 @@ public void CircularBuffer_WithDifferentSizeAndCapacity_BackReturnsLastArrayPosi
 
             Assert.That(buffer.Back(), Is.EqualTo(4));
         }
+
+        [Test]
+        public void CircularBuffer_Clear_ClearsContent()
+        {
+            var buffer = new CircularBuffer<int>(5, new[] { 4, 3, 2, 1, 0 });
+
+            buffer.Clear();
+
+            Assert.That(buffer.Size, Is.EqualTo(0));
+            Assert.That(buffer.Capacity, Is.EqualTo(5));
+            Assert.That(buffer.ToArray(), Is.EqualTo(new int[0]));
+        }
+
+        [Test]
+        public void CircularBuffer_Clear_WorksNormallyAfterClear()
+        {
+            var buffer = new CircularBuffer<int>(5, new[] { 4, 3, 2, 1, 0 });
+
+            buffer.Clear();
+            for (int i = 0; i < 5; i++)
+            {
+                buffer.PushBack(i);
+            }
+
+            Assert.That(buffer.Front(), Is.EqualTo(0));
+            for (int i = 0; i < 5; i++)
+            {
+                Assert.That(buffer[i], Is.EqualTo(i));
+            }
+        }
     }
 }
diff --git a/CircularBuffer/CircularBuffer.cs b/CircularBuffer/CircularBuffer.cs
@@ -250,6 +250,19 @@ public void PopFront()
             --_size;
         }
 
+        /// <summary>
+        /// Clears the contents of the array. Size = 0, Capacity is unchanged.
+        /// </summary>
+        /// <exception cref="NotImplementedException"></exception>
+        public void Clear()
+        {
+            // to clear we just reset everything.
+            _start = 0;
+            _end = 0;
+            _size = 0;
+            Array.Clear(_buffer, 0, _buffer.Length);
+        }
+
         /// <summary>
         /// Copies the buffer contents to an array, according to the logical
         /// contents of the buffer (i.e. independent of the internal