diff --git a/src/argument_parser.jl b/src/argument_parser.jl
index 24e958c..0c7be19 100644
--- a/src/argument_parser.jl
+++ b/src/argument_parser.jl
@@ -37,7 +37,8 @@ end
 
 function add_argument(args...; kwargs...)
     @warn """add_argument(...) is deprecated and will be removed before ArgParse2 is registered.
-             Please use add_argument!(...)""" maxlog=1
+             Please use add_argument!(...)""" maxlog = 1
+    add_argument!(args...; kwargs...)
 end
 
 function add_argument!(parser::ArgumentParser, name_or_flags::String...; kwargs...)
diff --git a/test/runtests.jl b/test/runtests.jl
index e061ab3..c1a18ae 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -414,6 +414,7 @@ end
 
     parser = ArgumentParser(description="Test missing prog")
     @test_logs (:warn, r"add_argument\(...\) is deprecated.*") add_argument(parser, "foo")
+    @test parse_args(parser, ["bar"]) === (foo = "bar",)
 end
 
 nothing