From 83cb73a0452c39cbaf26b0c1d05ed5a219af8d24 Mon Sep 17 00:00:00 2001
From: Ali Mohammad Pur <ali.mpfard@gmail.com>
Date: Fri, 31 Mar 2023 04:02:23 +0330
Subject: [PATCH] LibCore: Don't assume ArgsParser arguments are non-empty

This was fine before as the last entry was a null string (which could be
printed), but we no longer use C-style sentinel-terminated arrays for
arguments.
---
 Userland/Libraries/LibCore/ArgsParser.cpp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/Userland/Libraries/LibCore/ArgsParser.cpp b/Userland/Libraries/LibCore/ArgsParser.cpp
index 4f1f6f4a0c..30eb89bccb 100644
--- a/Userland/Libraries/LibCore/ArgsParser.cpp
+++ b/Userland/Libraries/LibCore/ArgsParser.cpp
@@ -27,13 +27,20 @@ ArgsParser::ArgsParser()
 
 bool ArgsParser::parse(Span<StringView> arguments, FailureBehavior failure_behavior)
 {
-    auto fail = [this, name = arguments[0], failure_behavior] {
+    auto fail_impl = [this, failure_behavior](StringView name) {
         if (failure_behavior == FailureBehavior::PrintUsage || failure_behavior == FailureBehavior::PrintUsageAndExit)
             print_usage(stderr, name);
         if (failure_behavior == FailureBehavior::Exit || failure_behavior == FailureBehavior::PrintUsageAndExit)
             exit(1);
     };
 
+    if (arguments.is_empty()) {
+        fail_impl("<exe>"sv);
+        return false;
+    }
+
+    auto fail = [name = arguments[0], &fail_impl] { fail_impl(name); };
+
     OptionParser parser;
 
     Vector<OptionParser::Option> long_options;