Fix Excessive Encoding in Test Logs (#92286)

* Removed special encoding that was rendering the test logs near
impossible to read properly.

* Adjusted the offending test to print the invalid character's hex code
instead, and fixed it alongside its sibling test because they didn't
handle all correct/incorrect cases properly.

* Added special handling for illegal XML characters in the test results'
XML logs.

* Simplified the sanitizing algorithm to one pass, as per Dan's feedback.

Author: ivdiazsa

src/tests/Common/XUnitWrapperLibrary/TestSummary.cs

@@ -2,10 +2,11 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System;
-using System.IO;
 using System.Collections.Generic;
+using System.IO;
 using System.Text;
 using System.Xml;
+
 namespace XUnitWrapperLibrary;
 
 public class TestSummary
@@ -43,8 +44,14 @@ public string ToXmlString()
             testResultSb.Append($@"<test name=""{Name}"" type=""{ContainingTypeName}"""
                               + $@" method=""{MethodName}"" time=""{Duration.TotalSeconds:F6}""");
 
+            // GH dotnet/runtime issue #92092: It is possible for tests to have
+            // illegal XML characters in their output. So, we have to sanitize said
+            // output before writing it down to the XML log because otherwise, the
+            // python XML parser crashes. The way we clean it is by replacing said
+            // characters with their hexadecimal notation in SanitizeOutput().
+
             string outputElement = !string.IsNullOrWhiteSpace(Output)
-                                 ? $"<output><![CDATA[{XmlConvert.EncodeName(Output)}]]></output>"
+                                 ? $"<output><![CDATA[{SanitizeOutput(Output)}]]></output>"
                                  : string.Empty;
 
             if (Exception is not null)
@@ -95,12 +102,36 @@ public string ToXmlString()
 
             return testResultSb.ToString();
         }
+
+        private string SanitizeOutput(string output)
+        {
+            StringBuilder sanitizedOutput = new StringBuilder();
+
+            // Check each character in the given test's output:
+            //   * If it's a legal XML character, then write it as is.
+            //   * Otherwise, write it in its hexadecimal notation.
+
+            foreach (char ch in output)
+            {
+                if (XmlConvert.IsXmlChar(ch))
+                {
+                    sanitizedOutput.Append(ch);
+                }
+                else
+                {
+                    int charCode = Convert.ToInt32(ch);
+                    sanitizedOutput.AppendFormat("_0x{0}_", charCode.ToString("X"));
+                }
+            }
+
+            return sanitizedOutput.ToString();
+        }
     }
 
-    public int PassedTests { get; private set; }
-    public int FailedTests { get; private set; }
-    public int SkippedTests { get; private set; }
-    public int TotalTests { get; private set; }
+    public int PassedTests { get; private set; } = 0;
+    public int FailedTests { get; private set; } = 0;
+    public int SkippedTests { get; private set; } = 0;
+    public int TotalTests { get; private set; } = 0;
 
     private readonly List<TestResult> _testResults = new();
     private DateTime _testRunStart = DateTime.Now;

src/tests/JIT/Regression/VS-ia64-JIT/M00/b119026/bug.cs

@@ -2,31 +2,50 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 //
 
+using System;
 using Xunit;
+
 public class test
 {
     static short si16;
     static uint su32;
+
     [Fact]
-    public static void TestEntryPoint()
+    public static int TestEntryPoint()
     {
-        si16 = -1;
-        su32 = (uint)si16;
-        System.Console.WriteLine(su32);
-        if (su32 == uint.MaxValue)
+        int exitCode = -1;
+        short i16 = -1;
+        uint u32 = (uint) i16;
+
+        Console.WriteLine(u32);
+
+        if (u32 == uint.MaxValue)
+        {
             System.Console.WriteLine("Pass");
+            exitCode = 100;
+        }
         else
+        {
             System.Console.WriteLine("Fail");
-        short i16 = -1;
-        uint u32 = (uint)i16;
-        System.Console.WriteLine(u32);
-        if (u32 == uint.MaxValue)
+            exitCode = 101;
+        }
+
+        si16 = -1;
+        su32 = (uint) si16;
+
+        Console.WriteLine(su32);
+
+        if (su32 == uint.MaxValue)
         {
             System.Console.WriteLine("Pass");
         }
         else
         {
             System.Console.WriteLine("Fail");
+            if (exitCode == 100)
+                exitCode = 101;
         }
+
+        return exitCode;
     }
 }

src/tests/JIT/Regression/VS-ia64-JIT/M00/b119026/charbug.cs

@@ -2,33 +2,50 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 //
 
+using System;
 using Xunit;
+
 public class test
 {
     static sbyte si8;
     static char sc;
+
     [Fact]
     public static int TestEntryPoint()
     {
+        int exitCode = -1;
         sbyte i8 = -1;
-        char c = (char)i8;
-        System.Console.WriteLine("{0}: {1}", c, ((ushort)c));
+        char c = (char) i8;
+
+        Console.WriteLine("{0:X}: {1}", Convert.ToUInt32(c), ((ushort)c));
+
         if (c == char.MaxValue)
-            System.Console.WriteLine("Pass");
+        {
+            Console.WriteLine("Pass");
+            exitCode = 100;
+        }
         else
-            System.Console.WriteLine("Fail");
+        {
+            Console.WriteLine("Fail");
+            exitCode = 101;
+        }
+
         si8 = -1;
         sc = (char)si8;
-        System.Console.WriteLine("{0}: {1}", sc, ((ushort)sc));
+
+        Console.WriteLine("{0:X}: {1}", Convert.ToUInt32(sc), ((ushort)sc));
+
         if (sc == char.MaxValue)
         {
             System.Console.WriteLine("Pass");
-            return 100;
         }
         else
         {
             System.Console.WriteLine("Fail");
-            return 1;
+            if (exitCode == 100)
+                exitCode = 101;
         }
+
+        return exitCode;
     }
 }