Userland/test: Handle '!' being used as a string

e.g. `test ! = !`.
Fixes SerenityOS#6465.

Userland/Utilities/test.cpp

@@ -356,15 +356,6 @@ static OwnPtr<Condition> parse_simple_expression(char* argv[])
  fatal_error("Unmatched \033[1m(");
  }
 
- if (arg == "!") {
- if (should_treat_expression_as_single_string(argv[optind]))
- return make<StringCompare>(move(arg), "", StringCompare::NotEqual);
- auto command = parse_complex_expression(argv);
- if (!command)
- fatal_error("Expected an expression after \033[1m!");
- return make<Not>(command.release_nonnull());
- }
-
  // Try to read a unary op.
  if (arg.starts_with('-') && arg.length() == 2) {
  optind++;
@@ -464,6 +455,17 @@ static OwnPtr<Condition> parse_simple_expression(char* argv[])
  --optind;
  return make<StringCompare>("", lhs, StringCompare::NotEqual);
  } else {
+ // Now that we know it's not a well-formed expression, see if it's actually a negation
+ if (lhs == "!") {
+ if (should_treat_expression_as_single_string(arg))
+ return make<StringCompare>(move(lhs), "", StringCompare::NotEqual);
+
+ auto command = parse_complex_expression(argv);
+ if (!command)
+ fatal_error("Expected an expression after \x1b[1m!");
+
+ return make<Not>(command.release_nonnull());
+ }
  --optind;
  return make<StringCompare>("", lhs, StringCompare::NotEqual);
  }