monogame-patcher: Work around terminal width issue

If the command is not executed inside a terminal the value of
Console.WindowWidth is 0 and thus we will get an exception from
CommandLineParser:

Unhandled Exception:
System.ArgumentOutOfRangeException: Length cannot be less than zero.
Parameter name: length
  at System.String.Substring ...
  at CommandLine.Text.HelpText.AddOption ...
  ...

So let's initialize the parser with settings and if WindowWidth is 0 we
just add 80 as the width.

Signed-off-by: aszlig <aszlig@nix.build>

2 files changed, 13 insertions, 1 deletions

diff --git a/pkgs/games/build-support/monogame-patcher/src/patcher.cs b/pkgs/games/build-support/monogame-patcher/src/patcher.cs
index cac60250..b35e44d6 100644
--- a/pkgs/games/build-support/monogame-patcher/src/patcher.cs
+++ b/pkgs/games/build-support/monogame-patcher/src/patcher.cs
@@ -128,7 +128,17 @@ class ReplaceCall : Command {
 
 public class patcher {
     public static int Main(string[] args) {
-        Parser.Default.ParseArguments<FixFileStreamsCmd, ReplaceCallCmd>(args)
+        var parser = new Parser((settings) => {
+            settings.EnableDashDash = true;
+            settings.HelpWriter = Console.Error;
+
+            // XXX: When not running in a terminal the width is 0, but the
+            //      CommandLine library expects it to be greater than zero.
+            if (Console.WindowWidth == 0)
+                settings.MaximumDisplayWidth = 80;
+        });
+
+        parser.ParseArguments<FixFileStreamsCmd, ReplaceCallCmd>(args)
             .WithParsed<FixFileStreamsCmd>(opts => new FixFileStreams(opts))
             .WithParsed<ReplaceCallCmd>(opts => new ReplaceCall(opts));
         return 0;
diff --git a/pkgs/games/build-support/monogame-patcher/src/test.sh b/pkgs/games/build-support/monogame-patcher/src/test.sh
index 80260c80..9c51cd7e 100644
--- a/pkgs/games/build-support/monogame-patcher/src/test.sh
+++ b/pkgs/games/build-support/monogame-patcher/src/test.sh
@@ -76,3 +76,5 @@ test "$(mono test2.exe)" = "can write"
 "$out/bin/monogame-patcher" fix-filestreams -i b.dll b
 
 test "$(mono test2.exe)" = "can not write"
+
+"$out/bin/monogame-patcher" --help 2>&1 | grep -q fix-filestreams