Method Tests

codegen/main.go:249–303

()

}

func (b *Build) Tests() *Generator {
	ifaces := b.Interfaces
	// @TODO dedupe
	// subIfaces has all interfaces except http.ResponseWriter
	subIfaces := ifaces[1:]

	var g Generator
	// Package header
	b.writeHeader(&g)
	g.Printf("import (\n")
	g.Printf(`"net/http"` + "\n")
	g.Printf(`"io"` + "\n")
	g.Printf(`"testing"` + "\n")
	g.Printf(")\n")
	g.Printf("\n")

	// TestWrap func
	g.Printf("func TestWrap(t *testing.T) {\n")
	combinations := 1 << uint(len(subIfaces))
	for i := 0; i < combinations; i++ {
		fields := make([]string, 0, len(subIfaces))
		fields = append(fields, "http.ResponseWriter")
		expected := make([]bool, len(ifaces))
		expected[0] = true
		for j, iface := range subIfaces {
			ok := i&(1<<uint(len(subIfaces)-j-1)) > 0
			expected[j+1] = ok
			if ok {
				fields = append(fields, iface.Name)
			}
		}
		g.Printf("// combination %d/%d\n", i+1, combinations)
		g.Printf("{\n")
		g.Printf(`t.Log("%s")`+"\n", strings.Join(fields, ", "))
		g.Printf("inner := struct{\n%s\n}{}\n", strings.Join(fields, "\n"))
		g.Printf("w := Wrap(inner, Hooks{})\n")
		for i, iface := range ifaces {
			g.Printf("if _, ok := w.(%s); ok != %t {\n", iface.Name, expected[i])
			g.Printf("t.Error(\"unexpected interface\");\n")
			g.Printf("}\n")
		}
		g.Printf(`
if w, ok := w.(Unwrapper); ok {
  if w.Unwrap() != inner {
    t.Error("w.Unwrap() failed")
  }
} else {
	t.Error("Unwrapper interface not implemented")
}`)
		g.Printf("}\n")
		g.Printf("\n")
	}
	g.Printf("}\n")
	return &g
}

type Interfaces []*Interface