Create ResultTextEncodingTests.cs

Author: SimonCropp

src/StaticSettingsTests/ResultTextEncodingTests.cs

@@ -0,0 +1,61 @@
+// Lives here, rather than in Verify.Tests, since UseEncoding is a static setting, and this
+// project runs serially with BaseTest resetting it between tests.
+public class ResultTextEncodingTests :
+    BaseTest
+{
+    // Latin1 writes no preamble, so nothing on disk tells a reader the file is not UTF8. Reading
+    // it as UTF8 turns the 0xE9 byte into U+FFFD, which is what makes this the case that catches
+    // VerifyResult.Text ignoring the configured encoding.
+    const string value = "café";
+
+    [Fact]
+    public async Task ReadsExistingVerifiedWithConfiguredEncoding()
+    {
+        VerifierSettings.UseEncoding(Encoding.Latin1);
+
+        using var temp = new TempDirectory();
+        await File.WriteAllTextAsync(VerifiedPath(temp), value, Encoding.Latin1);
+
+        var result = await Verify(value, Settings(temp));
+
+        Assert.Equal(value, result.Text);
+    }
+
+    [Fact]
+    public async Task RoundTripsWhatVerifyWrote()
+    {
+        VerifierSettings.UseEncoding(Encoding.Latin1);
+
+        using var temp = new TempDirectory();
+        var settings = Settings(temp);
+        settings.AutoVerify();
+
+        var result = await Verify(value, settings);
+
+        var file = result.Files.Single();
+        Assert.Equal(Encoding.Latin1.GetBytes(value), await File.ReadAllBytesAsync(file));
+        Assert.Equal(value, result.Text);
+    }
+
+    [Fact]
+    public async Task DefaultEncodingIsUnaffected()
+    {
+        using var temp = new TempDirectory();
+        await File.WriteAllTextAsync(VerifiedPath(temp), value, new UTF8Encoding(true));
+
+        var result = await Verify(value, Settings(temp));
+
+        Assert.Equal(value, result.Text);
+    }
+
+    static VerifySettings Settings(TempDirectory temp)
+    {
+        var settings = new VerifySettings();
+        settings.UseDirectory(temp);
+        settings.DisableDiff();
+        return settings;
+    }
+
+    static string VerifiedPath(TempDirectory temp, [CallerMemberName] string name = "") =>
+        temp.BuildPath($"{nameof(ResultTextEncodingTests)}.{name}.verified.txt");
+}