panic on Run with no selected nodes #483
Description
If there's an application with no nodes selected, instead of returning an error, Context.Run panics.
Reproduction:
func TestRegression(t *testing.T) {
var emptyCLI struct{}
parser, err := kong.New(&emptyCLI)
assert.NoError(t, err)
kctx, err := parser.Parse([]string{})
assert.NoError(t, err)
err = kctx.Run()
assert.Error(t, err)
assert.Contains(t, err.Error(), "no command selected")
}This test passes against v1.2.1 but not against 1.6.0.
git bisect indicates that the issue was introduced in 2544d3f.