Add Encoding support to TextSnapshotStrategy and SnapshotTestBuilder.

Author: xaviersolau

src/libs/SoloX.CodeQuality.Test.Helpers/Snapshot/ISnapshotTestBuilder.cs

@@ -8,6 +8,7 @@
 
 using System.IO;
 using System.Runtime.CompilerServices;
+using System.Text;
 
 namespace SoloX.CodeQuality.Test.Helpers.Snapshot
 {
@@ -57,6 +58,18 @@ public interface ISnapshotTestBuilder
         /// <returns>An updated snapshot test builder configured to use PNG image comparison.</returns>
         ISnapshotTestBuilder<Stream> WithPngStrategy(double differencesThreshold = 0.0);
 
+        /// <summary>
+        /// Configures the snapshot test builder to use a UTF-8 encoded text-based comparison strategy.
+        /// </summary>
+        /// <remarks>Use this method when the expected and actual values should be compared as plain text using UTF-8 encoding,
+        /// such as for verifying file contents or string outputs.</remarks>
+        /// <param name="ignoreWhitespace">Indicates whether to ignore differences in whitespace when comparing text. If true, all whitespace characters
+        /// are treated as equivalent, and differences in whitespace will not cause the test to fail. Default is true.</param>
+        /// <param name="ignoreCase">Indicates whether to ignore case differences when comparing text. If true, uppercase and lowercase characters
+        /// are treated as equivalent, and differences in case will not cause the test to fail. Default is false.</param>
+        /// <returns>An instance of the snapshot test builder configured to compare string content using a UTF-8 text strategy.</returns>
+        ISnapshotTestBuilder<string> WithUtf8TextStrategy(bool ignoreWhitespace = true, bool ignoreCase = false);
+
         /// <summary>
         /// Configures the snapshot test builder to use a text-based comparison strategy.
         /// </summary>
@@ -66,8 +79,9 @@ public interface ISnapshotTestBuilder
         /// are treated as equivalent, and differences in whitespace will not cause the test to fail. Default is true.</param>
         /// <param name="ignoreCase">Indicates whether to ignore case differences when comparing text. If true, uppercase and lowercase characters
         /// are treated as equivalent, and differences in case will not cause the test to fail. Default is false.</param>
+        /// <param name="encoding">The text encoding to use when reading and writing text files. If null, the default encoding will be used.</param>
         /// <returns>An instance of the snapshot test builder configured to compare string content using a text strategy.</returns>
-        ISnapshotTestBuilder<string> WithTextStrategy(bool ignoreWhitespace = true, bool ignoreCase = false);
+        ISnapshotTestBuilder<string> WithTextStrategy(bool ignoreWhitespace = true, bool ignoreCase = false, Encoding? encoding = null);
     }
 
     /// <summary>

src/libs/SoloX.CodeQuality.Test.Helpers/Snapshot/Impl/TextSnapshotStrategy.cs

@@ -7,6 +7,7 @@
 // ----------------------------------------------------------------------
 
 using System.IO;
+using System.Text;
 using System.Threading.Tasks;
 using DiffPlex.Renderer;
 
@@ -23,14 +24,16 @@ public class TextSnapshotStrategy : ISnapshotStrategy<string>
     {
         private readonly bool ignoreWhitespace;
         private readonly bool ignoreCase;
+        private readonly Encoding encoding;
 
         /// <inheritdoc/>
         public string FileExtension => "txt";
 
-        public TextSnapshotStrategy(bool ignoreWhitespace = true, bool ignoreCase = false)
+        public TextSnapshotStrategy(bool ignoreWhitespace = true, bool ignoreCase = false, Encoding? encoding = null)
         {
             this.ignoreWhitespace = ignoreWhitespace;
             this.ignoreCase = ignoreCase;
+            this.encoding = encoding ?? Encoding.Default;
         }
 
         /// <inheritdoc/>
@@ -41,13 +44,13 @@ public Task SaveAsync(string snapshotFile, string snapshotData)
                 File.Delete(snapshotFile);
             }
 
-            return File.WriteAllTextAsync(snapshotFile, snapshotData);
+            return File.WriteAllTextAsync(snapshotFile, snapshotData, this.encoding);
         }
 
         /// <inheritdoc/>
         public async Task<CompareSnapshotResult<string>> CompareAsync(string snapshotReferenceFile, string snapshotData)
         {
-            var referenceText = await File.ReadAllTextAsync(snapshotReferenceFile).ConfigureAwait(false);
+            var referenceText = await File.ReadAllTextAsync(snapshotReferenceFile, this.encoding).ConfigureAwait(false);
             var snapshotDiffs = UnidiffRenderer.GenerateUnidiff(
                 referenceText,
                 snapshotData,

src/libs/SoloX.CodeQuality.Test.Helpers/Snapshot/SnapshotTestBuilder.cs

@@ -9,6 +9,7 @@
 using System;
 using System.IO;
 using System.Runtime.CompilerServices;
+using System.Text;
 using SoloX.CodeQuality.Test.Helpers.Snapshot.Impl;
 
 namespace SoloX.CodeQuality.Test.Helpers.Snapshot
@@ -76,9 +77,14 @@ public ISnapshotTestBuilder<Stream> WithPngStrategy(double differencesThreshold
                 return builder;
             }
 
-            public ISnapshotTestBuilder<string> WithTextStrategy(bool ignoreWhitespace = true, bool ignoreCase = false)
+            public ISnapshotTestBuilder<string> WithUtf8TextStrategy(bool ignoreWhitespace = true, bool ignoreCase = false)
             {
-                var builder = new SnapshotTestBuilderInternal<string>(this, new TextSnapshotStrategy(ignoreWhitespace, ignoreCase));
+                return WithTextStrategy(ignoreWhitespace, ignoreCase, Encoding.UTF8);
+            }
+
+            public ISnapshotTestBuilder<string> WithTextStrategy(bool ignoreWhitespace = true, bool ignoreCase = false, Encoding? encoding = null)
+            {
+                var builder = new SnapshotTestBuilderInternal<string>(this, new TextSnapshotStrategy(ignoreWhitespace, ignoreCase, encoding));
 
                 return builder;
             }

src/tests/SoloX.CodeQuality.Test.Helpers.UTest/Snapshot/SnapshotTestBuilderTest.cs

@@ -6,6 +6,7 @@
 // </copyright>
 // ----------------------------------------------------------------------
 
+using System.Text;
 using Shouldly;
 using SoloX.CodeQuality.Test.Helpers.Snapshot;
 using Xunit;
@@ -48,6 +49,40 @@ public async Task ItShouldGenerateTextSnapshotAsync()
             }
         }
 
+        [Fact]
+        public async Task ItShouldGenerateUtf8TextSnapshotAsync()
+        {
+            var sh = SnapshotTestBuilder
+                .Create()
+                .WithLocation(".")
+                .WithUtf8TextStrategy()
+                .Build();
+
+            var expectedFile = @$"./Snapshots/{nameof(ItShouldGenerateUtf8TextSnapshotAsync)}.snapshot.ref.txt";
+
+            try
+            {
+                var someGeneratedText = "some generated utf8 text";
+
+                await sh.CompareSnapshotAsync(nameof(ItShouldGenerateUtf8TextSnapshotAsync), someGeneratedText);
+
+                // Check that the snapshot reference file exists and has been generated with the same content as the generated text
+                File.Exists(expectedFile)
+                    .ShouldBeTrue();
+
+                var generatedText = await File.ReadAllTextAsync(expectedFile, Encoding.UTF8);
+
+                generatedText.ShouldBe(someGeneratedText);
+            }
+            finally
+            {
+                if (File.Exists(expectedFile))
+                {
+                    File.Delete(expectedFile);
+                }
+            }
+        }
+
         [Fact]
         public async Task ItShouldReplaceTextSnapshotAsync()
         {