/
types.go
172 lines (157 loc) · 3.67 KB
/
types.go
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// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package bind
import (
"fmt"
"go/types"
"log"
"strings"
)
type ifaceSummary struct {
iface *types.Interface
callable []*types.Func
implementable bool
}
func makeIfaceSummary(iface *types.Interface) ifaceSummary {
summary := ifaceSummary{
iface: iface,
implementable: true,
}
methodset := types.NewMethodSet(iface)
for i := 0; i < methodset.Len(); i++ {
obj := methodset.At(i).Obj()
if !obj.Exported() {
summary.implementable = false
continue
}
m, ok := obj.(*types.Func)
if !ok {
log.Panicf("unexpected methodset obj: %s (%T)", obj, obj)
}
if !isImplementable(m.Type().(*types.Signature)) {
summary.implementable = false
}
if isCallable(m) {
summary.callable = append(summary.callable, m)
}
}
return summary
}
func isCallable(t *types.Func) bool {
// TODO(crawshaw): functions that are not implementable from
// another language may still be callable (for example, a
// returned value with an unexported type can be treated as
// an opaque value by the caller). This restriction could be
// lifted.
return isImplementable(t.Type().(*types.Signature))
}
func isImplementable(sig *types.Signature) bool {
params := sig.Params()
for i := 0; i < params.Len(); i++ {
if !isExported(params.At(i).Type()) {
return false
}
}
res := sig.Results()
for i := 0; i < res.Len(); i++ {
if !isExported(res.At(i).Type()) {
return false
}
}
return true
}
func exportedMethodSet(T types.Type) []*types.Func {
var methods []*types.Func
methodset := types.NewMethodSet(T)
for i := 0; i < methodset.Len(); i++ {
obj := methodset.At(i).Obj()
if !obj.Exported() {
continue
}
// Skip methods from the embedded classes, so that
// only methods that are implemented in Go are included.
if pref := pkgFirstElem(obj.Pkg()); pref == "Java" || pref == "ObjC" {
continue
}
switch obj := obj.(type) {
case *types.Func:
methods = append(methods, obj)
default:
log.Panicf("unexpected methodset obj: %s", obj)
}
}
return methods
}
func exportedFields(T *types.Struct) []*types.Var {
var fields []*types.Var
for i := 0; i < T.NumFields(); i++ {
f := T.Field(i)
if !f.Exported() {
continue
}
fields = append(fields, f)
}
return fields
}
func isErrorType(t types.Type) bool {
return types.Identical(t, types.Universe.Lookup("error").Type())
}
func isExported(t types.Type) bool {
if isErrorType(t) {
return true
}
switch t := t.(type) {
case *types.Basic:
return true
case *types.Named:
return t.Obj().Exported()
case *types.Pointer:
return isExported(t.Elem())
default:
return true
}
}
func isRefType(t types.Type) bool {
if isErrorType(t) {
return false
}
switch t := t.(type) {
case *types.Named:
switch u := t.Underlying().(type) {
case *types.Interface:
return true
default:
panic(fmt.Sprintf("unsupported named type: %s / %T", u, u))
}
case *types.Pointer:
return isRefType(t.Elem())
default:
return false
}
}
func isNullableType(t types.Type) bool {
return types.AssignableTo(types.Typ[types.UntypedNil].Underlying(), t) || t.String() == "string" // string is mapped to NSString*, which is nullable
}
func typePkgFirstElem(t types.Type) string {
nt, ok := t.(*types.Named)
if !ok {
return ""
}
return pkgFirstElem(nt.Obj().Pkg())
}
func pkgFirstElem(p *types.Package) string {
if p == nil {
return ""
}
path := p.Path()
idx := strings.Index(path, "/")
if idx == -1 {
return path
}
return path[:idx]
}
func isWrapperType(t types.Type) bool {
e := typePkgFirstElem(t)
return e == "Java" || e == "ObjC"
}