diff --git a/parse.go b/parse.go
index 0bdddc7..c88faae 100644
--- a/parse.go
+++ b/parse.go
@@ -85,13 +85,6 @@ func MustParse(dest ...interface{}) *Parser {
 
 // mustParse is a helper that facilitates testing
 func mustParse(config Config, dest ...interface{}) *Parser {
-	if config.Exit == nil {
-		config.Exit = os.Exit
-	}
-	if config.Out == nil {
-		config.Out = os.Stdout
-	}
-
 	p, err := NewParser(config, dest...)
 	if err != nil {
 		fmt.Fprintln(config.Out, err)
diff --git a/parse_test.go b/parse_test.go
index 06e7a76..1512800 100644
--- a/parse_test.go
+++ b/parse_test.go
@@ -1735,3 +1735,11 @@ func TestSubcommandGlobalFlag_InCommand_Strict_Inner(t *testing.T) {
 	assert.False(t, args.Global)
 	assert.True(t, args.Sub.Guard)
 }
+
+func TestExitFunctionAndOutStreamGetFilledIn(t *testing.T) {
+	var args struct{}
+	p, err := NewParser(Config{}, &args)
+	require.NoError(t, err)
+	assert.NotNil(t, p.config.Exit) // go prohibits function pointer comparison
+	assert.Equal(t, p.config.Out, os.Stdout)
+}