V2

1 files changed, 57 insertions, 0 deletions

diff --git a/flags_test.go b/flags_test.go
new file mode 100644
index 0000000..374a6cc
--- /dev/null
+++ b/flags_test.go
@@ -0,0 +1,57 @@
+package complete
+
+import (
+	"flag"
+	"fmt"
+	"strconv"
+	"testing"
+)
+
+func TestFlags(t *testing.T) {
+	t.Parallel()
+
+	var (
+		tr boolValue = true
+		fl boolValue = false
+	)
+
+	fs := flag.NewFlagSet("test", flag.ExitOnError)
+	fs.Var(&tr, "foo", "")
+	fs.Var(&fl, "bar", "")
+	fs.String("foo-bar", "", "")
+	cmp := FlagSet(fs)
+
+	Test(t, cmp, "", []string{"-foo", "-bar", "-foo-bar", "-h"})
+	Test(t, cmp, "-foo", []string{"-foo", "-foo-bar"})
+	Test(t, cmp, "-foo ", []string{"false"})
+	Test(t, cmp, "-foo=", []string{"false"})
+	Test(t, cmp, "-bar ", []string{"-foo", "-bar", "-foo-bar", "-h"})
+	Test(t, cmp, "-bar=", []string{})
+}
+
+type boolValue bool
+
+func (b *boolValue) Set(s string) error {
+	v, err := strconv.ParseBool(s)
+	if err != nil {
+		return fmt.Errorf("bad value %q for bool flag", s)
+	}
+	*b = boolValue(v)
+	return nil
+}
+
+func (b *boolValue) Get() interface{} { return bool(*b) }
+
+func (b *boolValue) String() string { return strconv.FormatBool(bool(*b)) }
+
+func (b *boolValue) IsBoolFlag() bool { return true }
+
+func (b *boolValue) Predict(_ string) []string {
+	// If false, typing the bool flag is expected to turn it on, so there is nothing to complete
+	// after the flag.
+	if *b == false {
+		return nil
+	}
+	// Otherwise, suggest only to turn it off.
+	return []string{"false"}
+}