feat:ZeroLit for alias

Author: luoliwoshang

Diff for: codebuild.go

@@ -768,6 +768,9 @@ retry:
 	case *types.Named:
 		typ = p.getUnderlying(t)
 		goto retry
+	case *typesutil.Alias:
+		typ = typesutil.Unalias(t)
+		goto retry
 	}
 	ret := &ast.CompositeLit{}
 	switch t := typ.(type) {

Diff for: package_test.go

@@ -667,6 +667,22 @@ func main() {
 `)
 }
 
+func TestZeroLitAlias(t *testing.T) {
+	pkg := newPackage("main", true)
+	bar := pkg.AliasType("bar", types.Typ[types.Float64])
+	results := types.NewTuple(types.NewVar(token.NoPos, pkg.Types, "", bar))
+	pkg.NewFunc(nil, "main", nil, results, false).BodyStart(pkg).
+		ZeroLit(bar).Return(1).End()
+	domTest(t, pkg, `package main
+
+type bar = float64
+
+func main() bar {
+	return 0
+}
+`)
+}
+
 func TestZeroLitAllTypes(t *testing.T) {
 	pkg := newMainPackage()
 	tyString := types.Typ[types.String]