StringSliceFlag.ValueFromContext() as convenient accessor

flag_string_slice.go

@@ -186,6 +186,11 @@ func (f *StringSliceFlag) Apply(set *flag.FlagSet) error {
 	return nil
 }
 
+// ValueFromContext returns the flag’s value in the given Context.
+func (f *StringSliceFlag) ValueFromContext(ctx *Context) []string {
+	return ctx.StringSlice(f.Name)
+}
+
 // StringSlice looks up the value of a local StringSliceFlag, returns
 // nil if not found
 func (c *Context) StringSlice(name string) []string {

flag_test.go

@@ -630,6 +630,14 @@ func TestStringSliceFlagApply_DefaultValueWithDestination(t *testing.T) {
 	expect(t, defValue, fl.Destination.Value())
 }
 
+func TestStringSliceFlagValueFromContext(t *testing.T) {
+	set := flag.NewFlagSet("test", 0)
+	set.Var(NewStringSlice("a", "b", "c"), "myflag", "doc")
+	ctx := NewContext(nil, set, nil)
+	f := &StringSliceFlag{Name: "myflag"}
+	expect(t, f.ValueFromContext(ctx), []string{"a", "b", "c"})
+}
+
 var intFlagTests = []struct {
 	name     string
 	expected string