comparers should apply to text

Author: SimonCropp

src/Verify/Compare/Comparer.cs

@@ -1,13 +1,12 @@
-using System;
-using System.IO;
+using System.IO;
 using System.Threading.Tasks;
 using Verify;
 
 static class Comparer
 {
-    public static async Task<CompareResult> Text(FilePair file, string scrubbedInput, bool ignoreTrailingWhitespace)
+    public static async Task<CompareResult> Text(FilePair file, string scrubbedInput, VerifySettings settings)
     {
-        scrubbedInput = Scrub(scrubbedInput, ignoreTrailingWhitespace);
+        scrubbedInput = Scrub(scrubbedInput, settings.ignoreTrailingWhitespace);
         FileHelpers.DeleteIfEmpty(file.Verified);
         if (!File.Exists(file.Verified))
         {
@@ -16,8 +15,9 @@ public static async Task<CompareResult> Text(FilePair file, string scrubbedInput
         }
 
         var verifiedText = await FileHelpers.ReadText(file.Verified);
-        verifiedText = Scrub(verifiedText, ignoreTrailingWhitespace);
-        if (string.Equals(verifiedText, scrubbedInput))
+        verifiedText = Scrub(verifiedText, settings.ignoreTrailingWhitespace);
+
+        if (await CompareStrings(scrubbedInput, verifiedText, settings))
         {
             return CompareResult.Equal;
         }
@@ -26,6 +26,29 @@ public static async Task<CompareResult> Text(FilePair file, string scrubbedInput
         return CompareResult.NotEqual;
     }
 
+    static Task<bool> CompareStrings(string scrubbedInput, string verifiedText, VerifySettings settings)
+    {
+        var extension = settings.ExtensionOrTxt();
+        if (settings.comparer != null)
+        {
+            using var stream1 = MemoryStream(scrubbedInput);
+            using var stream2 = MemoryStream(verifiedText);
+            return settings.comparer(settings, stream1, stream2);
+        }
+        if (SharedVerifySettings.TryGetComparer(extension, out var comparer))
+        {
+            using var stream1 = MemoryStream(scrubbedInput);
+            using var stream2 = MemoryStream(verifiedText);
+            return comparer(settings, stream1, stream2);
+        }
+        return Task.FromResult(string.Equals(verifiedText, scrubbedInput));
+    }
+
+    static MemoryStream MemoryStream(string text)
+    {
+        return new MemoryStream(FileHelpers.Utf8NoBOM.GetBytes(text));
+    }
+
     static string Scrub(string scrubbedInput, bool ignoreTrailingWhitespace)
     {
         scrubbedInput = scrubbedInput.Replace("\r\n", "\n");

src/Verify/Verifier/InnerVerifier_Stream.cs

@@ -65,7 +65,7 @@ static async Task<CompareResult> GetResult(VerifySettings settings, FilePair fil
         {
             var readAsString = await stream.ReadAsString();
             var scrubbedInput = ApplyScrubbers.Apply(readAsString, settings.instanceScrubbers);
-            return await Comparer.Text(file, scrubbedInput, settings.ignoreTrailingWhitespace);
+            return await Comparer.Text(file, scrubbedInput, settings);
         }
 
         return await Comparer.Streams(settings, stream, file);
@@ -94,7 +94,7 @@ async Task VerifyInfo(VerifyEngine engine, VerifySettings settings, object? info
 
         var scrubbedInput = ApplyScrubbers.Apply(formatJson, settings.instanceScrubbers);
 
-        var result = await Comparer.Text(file, scrubbedInput, settings.ignoreTrailingWhitespace);
+        var result = await Comparer.Text(file, scrubbedInput, settings);
         engine.HandleCompareResult(result, file);
     }
 }

src/Verify/Verifier/InnerVerifier_Text.cs

@@ -20,7 +20,7 @@ public async Task Verify(string input, VerifySettings? settings = null)
 
         var scrubbedInput = ApplyScrubbers.Apply(input, settings.instanceScrubbers);
 
-        var result = await Comparer.Text(file, scrubbedInput, settings.ignoreTrailingWhitespace);
+        var result = await Comparer.Text(file, scrubbedInput, settings);
         engine.HandleCompareResult(result, file);
         await engine.ThrowIfRequired();
     }