Fixes incorrect XML header for encoding #1322 (#1323)

docs/CHANGELOG-v2.md

@@ -30,6 +30,12 @@ See [upgrade notes][1] for helpful information when upgrading from previous vers
 
 ## Unreleased
 
+What's changed since v2.5.2:
+
+- Bug fixes:
+  - Fixed incorrect XML header for encoding by @BernieWhite.
+    [#1322](https://github.com/microsoft/PSRule/issues/1322)
+
 ## v2.5.2
 
 What's changed since v2.5.1:

src/PSRule/Pipeline/Output/NUnit3OutputWriter.cs

@@ -2,6 +2,7 @@
 // Licensed under the MIT License.
 
 using System;
+using System.IO;
 using System.Linq;
 using System.Text;
 using System.Threading;
@@ -14,13 +15,8 @@ namespace PSRule.Pipeline.Output
 {
     internal sealed class NUnit3OutputWriter : SerializationOutputWriter<InvokeResult>
     {
-        private readonly StringBuilder _Builder;
-
         internal NUnit3OutputWriter(PipelineWriter inner, PSRuleOption option)
-            : base(inner, option)
-        {
-            _Builder = new StringBuilder();
-        }
+            : base(inner, option) { }
 
         public override void WriteObject(object sendToPipeline, bool enumerateCollection)
         {
@@ -37,7 +33,8 @@ protected override string Serialize(InvokeResult[] o)
                 Encoding = Encoding.UTF8, // Consider using: Option.Output.GetEncoding()
                 // Consider using: Indent = true,
             };
-            using var xml = XmlWriter.Create(_Builder, settings);
+            using var writer = new OutputStringWriter(Option);
+            using var xml = XmlWriter.Create(writer, settings);
             xml.WriteStartDocument(standalone: false);
 
             float time = o.Sum(r => r.Time);
@@ -107,7 +104,7 @@ protected override string Serialize(InvokeResult[] o)
             xml.WriteEndElement();
             xml.WriteEndDocument();
             xml.Flush();
-            return _Builder.ToString();
+            return writer.ToString();
         }
 
         private static void VisitFixture(XmlWriter xml, TestFixture fixture)

src/PSRule/Pipeline/Output/OutputStringWriter.cs

@@ -0,0 +1,21 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+using System.IO;
+using System.Text;
+using PSRule.Configuration;
+
+namespace PSRule.Pipeline.Output
+{
+    internal sealed class OutputStringWriter : StringWriter
+    {
+        private readonly Encoding _Encoding;
+
+        public OutputStringWriter(PSRuleOption option)
+        {
+            _Encoding = option.Output.GetEncoding();
+        }
+
+        public override Encoding Encoding => _Encoding;
+    }
+}

tests/PSRule.Tests/OutputWriterTests.cs

@@ -299,6 +299,8 @@ public void NUnit3()
             var doc = new XmlDocument();
             doc.LoadXml(s);
 
+            var declaration = doc.ChildNodes.Item(0) as XmlDeclaration;
+            Assert.Equal("utf-8", declaration.Encoding);
             var xml = doc["test-results"]["test-suite"].OuterXml.Replace(Environment.NewLine, "\r\n");
             Assert.Equal("<test-suite type=\"TestFixture\" name=\"TestObject1\" executed=\"True\" result=\"Failure\" success=\"False\" time=\"0\" asserts=\"3\" description=\"\"><results><test-case description=\"This is rule 001.\" name=\"TestObject1 -- rule-001\" time=\"0\" asserts=\"0\" success=\"True\" result=\"Success\" executed=\"True\" /><test-case description=\"This is rule 002.\" name=\"TestObject1 -- rule-002\" time=\"0\" asserts=\"0\" success=\"False\" result=\"Failure\" executed=\"True\"><failure><message><![CDATA[Recommendation for rule 002\r\n]]></message><stack-trace><![CDATA[]]></stack-trace></failure></test-case><test-case description=\"This is rule 002.\" name=\"TestObject1 -- rule-002\" time=\"0\" asserts=\"0\" success=\"False\" result=\"Failure\" executed=\"True\"><failure><message><![CDATA[Recommendation for rule 002\r\n]]></message><stack-trace><![CDATA[]]></stack-trace></failure></test-case><test-case description=\"Synopsis &quot;with quotes&quot;.\" name=\"TestObject1 -- rule-002\" time=\"0\" asserts=\"0\" success=\"False\" result=\"Failure\" executed=\"True\"><failure><message><![CDATA[Recommendation for rule 002\r\n]]></message><stack-trace><![CDATA[]]></stack-trace></failure></test-case></results></test-suite>", xml);
         }