Add tests for required flags

required_flags_test.go

@@ -0,0 +1,60 @@
+package cli
+
+import (
+	"flag"
+	"testing"
+)
+
+func TestContext_CheckRequiredFlagsSuccess(t *testing.T) {
+	flags := []Flag{
+		StringFlag{
+			Name:     "required",
+			Required: true,
+		},
+		StringFlag{
+			Name: "optional",
+		},
+	}
+
+	set := flag.NewFlagSet("test", 0)
+	for _, f := range flags {
+		f.Apply(set)
+	}
+
+	e := set.Parse([]string{"--required", "foo"})
+	if e != nil {
+		t.Errorf("Expected no error parsing but there was one: %s", e)
+	}
+
+	err := checkRequiredFlags(flags, set)
+	if err != nil {
+		t.Error("Expected flag parsing to be successful")
+	}
+}
+
+func TestContext_CheckRequiredFlagsFailure(t *testing.T) {
+	flags := []Flag{
+		StringFlag{
+			Name:     "required",
+			Required: true,
+		},
+		StringFlag{
+			Name: "optional",
+		},
+	}
+
+	set := flag.NewFlagSet("test", 0)
+	for _, f := range flags {
+		f.Apply(set)
+	}
+
+	e := set.Parse([]string{"--optional", "foo"})
+	if e != nil {
+		t.Errorf("Expected no error parsing but there was one: %s", e)
+	}
+
+	err := checkRequiredFlags(flags, set)
+	if err == nil {
+		t.Error("Expected flag parsing to be unsuccessful")
+	}
+}