this seems okay

config/new_test.go

@@ -0,0 +1,46 @@
+package config
+
+import (
+	"flag"
+	"os"
+	"testing"
+)
+
+func TestInit(t *testing.T) {
+	was := os.Args[:]
+	os.Args = []string{"program"}
+	flag.CommandLine = flag.NewFlagSet(os.Args[0], flag.ExitOnError)
+	defer func() {
+		os.Args = was[:]
+	}()
+
+	if err := Init(); err != nil {
+		t.Errorf("failed to init: %v", err)
+	}
+}
+
+func TestFromFile(t *testing.T) {
+	was := os.Args[:]
+	os.Args = []string{"program"}
+	flag.CommandLine = flag.NewFlagSet(os.Args[0], flag.ExitOnError)
+	defer func() {
+		os.Args = was[:]
+	}()
+
+	if err := fromFile(); err != nil {
+		t.Errorf("failed from file: %v", err)
+	}
+}
+
+func TestFromFlags(t *testing.T) {
+	was := os.Args[:]
+	os.Args = []string{"program"}
+	flag.CommandLine = flag.NewFlagSet(os.Args[0], flag.ExitOnError)
+	defer func() {
+		os.Args = was[:]
+	}()
+
+	if err := fromFlags(); err != nil {
+		t.Errorf("failed from flags: %v", err)
+	}
+}