added Remove method

Author: linkdotnet

CHANGELOG.md

@@ -6,6 +6,9 @@ All notable changes to **ValueStringBuilder** will be documented in this file. T
 
 ## [Unreleased]
 
+### Added
+ - Added `Remove` method.
+
 ## [0.9.1] - 2022-04-06
 
 This release brings extensions to the `ValueStringBuilder` API. For `v1.0` the `ValueStringBuilder` tries to be en par with the`System.Text.StringBuilder`.

LinkDotNet.StringBuilder.sln

@@ -13,6 +13,7 @@ EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = ".text", ".text", "{DA9229AB-1A57-414E-A81C-358FA8DAC2AF}"
 	ProjectSection(SolutionItems) = preProject
 		README.md = README.md
+		CHANGELOG.md = CHANGELOG.md
 	EndProjectSection
 EndProject
 Global

src/LinkDotNet.StringBuilder/ValueStringBuilder.cs

@@ -102,13 +102,51 @@ public void AppendLine(ReadOnlySpan<char> str)
     public bool TryCopyTo(Span<char> destination) => buffer[..bufferPosition].TryCopyTo(destination);
 
     /// <summary>
-    /// Clears the st
+    /// Clears the internal representation of the string.
     /// </summary>
+    /// <remarks>
+    /// This will not enforce some allocations or shrinking of the internal buffer.
+    /// </remarks>
     public void Clear()
     {
         bufferPosition = 0;
     }
 
+    /// <summary>
+    /// Removes a range of characters from this builder.
+    /// </summary>
+    /// <param name="startIndex">The inclusive index from where the string gets removed.</param>
+    /// <param name="length">The length of the slice to remove.</param>
+    /// <remarks>
+    /// This method will not affect the internal size of the string.
+    /// </remarks>
+    public void Remove(int startIndex, int length)
+    {
+        if (length < 0)
+        {
+            throw new ArgumentOutOfRangeException(nameof(length), "The given length can't be negative.");
+        }
+
+        if (startIndex < 0)
+        {
+            throw new ArgumentOutOfRangeException(nameof(startIndex), "The given start index can't be negative.");
+        }
+
+        if (length > Length - startIndex)
+        {
+            throw new ArgumentOutOfRangeException(nameof(length), "The given length is longer than the represented string.");
+        }
+
+        if (startIndex >= Length)
+        {
+            throw new ArgumentOutOfRangeException(nameof(startIndex), "The given startIndex is larger than the represented string.");
+        }
+
+        var beginIndex = startIndex + length;
+        buffer[beginIndex..bufferPosition].CopyTo(buffer[startIndex..]);
+        bufferPosition -= length;
+    }
+
     private void Grow(int capacity = 0)
     {
         var currentSize = buffer.Length;

tests/LinkDotNet.StringBuilder.UnitTests/ValueStringBuilderTests.cs

@@ -140,4 +140,39 @@ public void ShouldReturnEmptyStringWhenInitialized()
 
         stringBuilder.ToString().Should().Be(string.Empty);
     }
+
+    [Fact]
+    public void ShouldRemoveRange()
+    {
+        var stringBuilder = new ValueStringBuilder();
+        stringBuilder.Append("Hello World");
+
+        stringBuilder.Remove(0, 6);
+
+        stringBuilder.Length.Should().Be(5);
+        stringBuilder.ToString().Should().Be("World");
+    }
+
+    [Theory]
+    [InlineData(-1, 2)]
+    [InlineData(1, -2)]
+    [InlineData(90, 1)]
+    [InlineData(1, 90)]
+    public void ShouldThrowExceptionWhenNegativeStartIndex(int startIndex, int length)
+    {
+        var stringBuilder = new ValueStringBuilder();
+        stringBuilder.Append("Hello World");
+
+        try
+        {
+            stringBuilder.Remove(startIndex, length);
+        }
+        catch (ArgumentOutOfRangeException)
+        {
+            Assert.True(true);
+            return;
+        }
+
+        Assert.False(true);
+    }
 }