From dac463b196c938ec6c2adead0eb2effcad5a6f26 Mon Sep 17 00:00:00 2001
From: Joyless <65855333+Joy-less@users.noreply.github.com>
Date: Fri, 28 Feb 2025 21:27:54 +0000
Subject: [PATCH 1/3] Perf optimization & simplification in Replace

---
 .../ValueStringBuilder.Replace.cs                         | 8 +-------
 .../ValueStringBuilderExtensions.cs                       | 2 +-
 2 files changed, 2 insertions(+), 8 deletions(-)

diff --git a/src/LinkDotNet.StringBuilder/ValueStringBuilder.Replace.cs b/src/LinkDotNet.StringBuilder/ValueStringBuilder.Replace.cs
index 967515f..f581ec8 100644
--- a/src/LinkDotNet.StringBuilder/ValueStringBuilder.Replace.cs
+++ b/src/LinkDotNet.StringBuilder/ValueStringBuilder.Replace.cs
@@ -26,13 +26,7 @@ public readonly void Replace(char oldValue, char newValue, int startIndex, int c
         ArgumentOutOfRangeException.ThrowIfLessThan(startIndex, 0);
         ArgumentOutOfRangeException.ThrowIfGreaterThan(startIndex + count, Length);
 
-        for (var i = startIndex; i < startIndex + count; i++)
-        {
-            if (buffer[i] == oldValue)
-            {
-                buffer[i] = newValue;
-            }
-        }
+        buffer.Slice(startIndex, count).Replace(oldValue, newValue);
     }
 
     /// <summary>
diff --git a/src/LinkDotNet.StringBuilder/ValueStringBuilderExtensions.cs b/src/LinkDotNet.StringBuilder/ValueStringBuilderExtensions.cs
index 4487bbe..1d9dc51 100644
--- a/src/LinkDotNet.StringBuilder/ValueStringBuilderExtensions.cs
+++ b/src/LinkDotNet.StringBuilder/ValueStringBuilderExtensions.cs
@@ -29,7 +29,7 @@ public static ValueStringBuilder ToValueStringBuilder(this System.Text.StringBui
     {
         ArgumentNullException.ThrowIfNull(builder);
 
-        var valueStringBuilder = new ValueStringBuilder();
+        var valueStringBuilder = new ValueStringBuilder(builder.Length);
         foreach (var chunk in builder.GetChunks())
         {
             valueStringBuilder.Append(chunk.Span);

From 8814b6a9e071b61e1d8709abc3ca7749a0a743de Mon Sep 17 00:00:00 2001
From: Joyless <65855333+Joy-less@users.noreply.github.com>
Date: Sat, 1 Mar 2025 00:02:16 +0000
Subject: [PATCH 2/3] Optimize replace with one-length spans

---
 src/LinkDotNet.StringBuilder/ValueStringBuilder.Replace.cs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/LinkDotNet.StringBuilder/ValueStringBuilder.Replace.cs b/src/LinkDotNet.StringBuilder/ValueStringBuilder.Replace.cs
index f581ec8..ebf41f6 100644
--- a/src/LinkDotNet.StringBuilder/ValueStringBuilder.Replace.cs
+++ b/src/LinkDotNet.StringBuilder/ValueStringBuilder.Replace.cs
@@ -91,6 +91,12 @@ public void Replace(scoped ReadOnlySpan<char> oldValue, scoped ReadOnlySpan<char
             return;
         }
 
+        if (oldValue.Length == 1 && newValue.Length == 1)
+        {
+            Replace(oldValue[0], newValue[0], startIndex, count);
+            return;
+        }
+
         var index = startIndex;
         var remainingChars = count;
 

From 9939cd656c8daa8549ead03f8f884f7566bf8e4d Mon Sep 17 00:00:00 2001
From: Joyless <65855333+Joy-less@users.noreply.github.com>
Date: Mon, 3 Mar 2025 18:29:53 +0000
Subject: [PATCH 3/3] Update CHANGELOG.md

---
 CHANGELOG.md | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 10eb412..4e82b2c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,11 @@ All notable changes to **ValueStringBuilder** will be documented in this file. T
 
 ## [Unreleased]
 
+### Changed
+
+- Optimized `Replace(char, char)` (by @Joy-less in #241)
+- Optimized `Replace(ReadOnlySpan<char>, ReadOnlySpan<char>)` when both spans are length 1 (by @Joy-less in #241)
+
 ## [2.4.0] - 2025-02-21
 
 ### Added