Add Feature and FlagFeature{,Var}

Feature is essentially a boolean flag that can be safely mutated at run
time. FlagFeature{,Var} make Feature objects work with flags.

1 files changed, 21 insertions, 0 deletions

diff --git a/flag_test.go b/flag_test.go
index 91c6caa..1cc9ba8 100644
--- a/flag_test.go
+++ b/flag_test.go
@@ -11,6 +11,18 @@ import (
 	"go.awhk.org/core"
 )
 
+func TestFeature_Disable(t *testing.T) {
+	f := core.Feature{}
+	f.Disable()
+	(&core.T{T: t}).AssertEqual(false, f.Enabled())
+}
+
+func TestFeature_Enable(t *testing.T) {
+	f := core.Feature{}
+	f.Enable()
+	(&core.T{T: t}).AssertEqual(true, f.Enabled())
+}
+
 func TestFlag(s *testing.T) {
 	t := core.T{T: s}
 
@@ -21,6 +33,15 @@ func TestFlag(s *testing.T) {
 	t.AssertEqual(84, *fl)
 }
 
+func TestFlagFeature(s *testing.T) {
+	t := core.T{T: s}
+
+	fs := flag.NewFlagSet("", flag.PanicOnError)
+	ff := core.FlagFeature(fs, "some-feature", false, "")
+	t.AssertErrorIs(nil, fs.Parse([]string{"-some-feature"}))
+	t.AssertEqual(true, ff.Enabled())
+}
+
 func TestFlagVar(s *testing.T) {
 	t := core.T{T: s}