add test for case where environment var is not present

1 files changed, 9 insertions, 0 deletions

diff --git a/parse_test.go b/parse_test.go
index de36d67..c44fe00 100644
--- a/parse_test.go
+++ b/parse_test.go
@@ -557,6 +557,15 @@ func TestEnvironmentVariable(t *testing.T) {
 	assert.Equal(t, "bar", args.Foo)
 }
 
+func TestEnvironmentVariableNotPresent(t *testing.T) {
+	var args struct {
+		NotPresent string `arg:"env"`
+	}
+	os.Args = []string{"example"}
+	MustParse(&args)
+	assert.Equal(t, "", args.NotPresent)
+}
+
 func TestEnvironmentVariableOverrideName(t *testing.T) {
 	var args struct {
 		Foo string `arg:"env:BAZ"`