More simplification

CliFx/Utils/Polyfills.Regex.cs

@@ -0,0 +1,12 @@
+// ReSharper disable CheckNamespace
+
+#if NETSTANDARD2_0
+using System.Linq;
+using System.Text.RegularExpressions;
+
+internal static class RegexPolyfills
+{
+    public static Match[] ToArray(this MatchCollection matches) =>
+        matches.Cast<Match>().ToArray();
+}
+#endif

CliFx/Utils/Polyfills.Strings.cs

@@ -7,6 +7,6 @@ internal static class StringPolyfills
         str.Length > 0 && str[0] == c;
 
     public static bool EndsWith(this string str, char c) =>
-        str.Length > 0 && str[str.Length - 1] == c;
+        str.Length > 0 && str[^1] == c;
 }
 #endif

CliFx/Utils/StackFrame.cs

@@ -52,33 +52,35 @@ internal partial class StackFrame
     private const string NotSpace = @"[^\x20\t]";
 
     // Taken from https://github.com/atifaziz/StackTraceParser
-    private static readonly Regex Pattern = new(@"
+    private static readonly Regex Pattern = new(
+        $$"""
         ^
-            " + Space + @"*
+        {{Space}}*
-            \w+ " + Space + @"+
+        \w+ {{Space}}+
         (?<frame>
-                (?<type> " + NotSpace + @"+ ) \.
+            (?<type> {{NotSpace}}+ ) \.
-                (?<method> " + NotSpace + @"+? ) " + Space + @"*
+            (?<method> {{NotSpace}}+? ) {{Space}}*
-                (?<params>  \( ( " + Space + @"* \)
+            (?<params>  \( ( {{Space}}* \)
-                               |                    (?<pt> .+?) " + Space + @"+ (?<pn> .+?)
+                           |                    (?<pt> .+?) {{Space}}+ (?<pn> .+?)
-                                 (, " + Space + @"* (?<pt> .+?) " + Space + @"+ (?<pn> .+?) )* \) ) )
+                             (, {{Space}}* (?<pt> .+?) {{Space}}+ (?<pn> .+?) )* \) ) )
-                ( " + Space + @"+
+            ( {{Space}}+
                 ( # Microsoft .NET stack traces
-                    \w+ " + Space + @"+
+                \w+ {{Space}}+
                 (?<file> ( [a-z] \: # Windows rooted path starting with a drive letter
-                             | / )      # *nix rooted path starting with a forward-slash
+                         | / )      # Unix rooted path starting with a forward-slash
                          .+? )
-                    \: \w+ " + Space + @"+
+                \: \w+ {{Space}}+
                 (?<line> [0-9]+ ) \p{P}?
                 | # Mono stack traces
-                    \[0x[0-9a-f]+\] " + Space + @"+ \w+ " + Space + @"+
+                \[0x[0-9a-f]+\] {{Space}}+ \w+ {{Space}}+
                 <(?<file> [^>]+ )>
                 :(?<line> [0-9]+ )
                 )
             )?
         )
         \s*
-            $",
+        $
+        """,
         RegexOptions.IgnoreCase |
         RegexOptions.Multiline |
         RegexOptions.ExplicitCapture |
@@ -89,7 +91,7 @@ internal partial class StackFrame
 
     public static IEnumerable<StackFrame> ParseMany(string stackTrace)
     {
-        var matches = Pattern.Matches(stackTrace).Cast<Match>().ToArray();
+        var matches = Pattern.Matches(stackTrace).ToArray();
 
         if (matches.Length <= 0 || matches.Any(m => !m.Success))
         {