More robust absolute path computation for the enhanced stack traces.

Fix for #61

test/Ben.Demystifier.Test/EnhancedStackTraceTests.cs

@@ -0,0 +1,31 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Text;
+using Xunit;
+
+namespace Ben.Demystifier.Test
+{
+    public class EnhancedStackTraceTests
+    {
+        [Theory]
+        [InlineData(@"file://Sources\MySolution\Foo.cs", @"/MySolution/Foo.cs")]
+        [InlineData(@"d:\Public\Src\Foo.cs", @"d:/Public/Src/Foo.cs")]
+        // To be deterministic, the C# compiler can take a /pathmap command line option.
+        // This option force the compiler to emit the same bits even when their built from the
+        // differrent locations.
+        // The binaries built with the pathmap usually don't have an absolute path,
+        // but have some prefix like \.\.
+        // This test case makes sure that EhancedStackTrace can deal with such kind of paths.
+        [InlineData(@"\.\Public\Src\Foo.cs", @"/./Public/Src/Foo.cs")]
+        public void RelativePathIsConvertedToAnAbsolutePath(string original, string expected)
+        {
+            var converted = EnhancedStackTrace.TryGetFullPath(original);
+            Assert.Equal(expected, NormalizePath(converted));
+        }
+
+        // Used in tests to avoid platform-specific issues.
+        private static string NormalizePath(string path)
+            => path.Replace("\\", "/");
+    }
+}