switch to subset of flag to insulate us from stdlib evolution

fixtures/packagemode/flag.go

@@ -1,5 +1,23 @@
 package packagemode
 
+import "flag"
+
 //go:generate go run github.com/maxbrunsfeld/counterfeiter/v6 -generate
-//counterfeiter:generate -p flag
-//counterfeiter:generate -o flagcustomfakesdir -p flag
+//counterfeiter:generate -p github.com/maxbrunsfeld/counterfeiter/v6/fixtures/packagemode
+//counterfeiter:generate -o flagcustomfakesdir -p github.com/maxbrunsfeld/counterfeiter/v6/fixtures/packagemode
+
+func Arg(arg1 int) string {
+	return flag.Arg(arg1)
+}
+
+func Args() []string {
+	return flag.Args()
+}
+
+func Bool(arg1 string, arg2 bool, arg3 string) *bool {
+	return flag.Bool(arg1, arg2, arg3)
+}
+
+func BoolVar(arg1 *bool, arg2 string, arg3 bool, arg4 string) {
+	flag.BoolVar(arg1, arg2, arg3, arg4)
+}