blob: df3ea52125439c929827ed7ffc553d89d22e5eb5 [file] [log] [blame]
// Copyright 2020 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 typesinternal provides access to internal go/types APIs that are not
// yet exported.
package typesinternal
import (
"go/token"
"go/types"
"reflect"
"unsafe"
"golang.org/x/tools/internal/aliases"
)
func SetUsesCgo(conf *types.Config) bool {
v := reflect.ValueOf(conf).Elem()
f := v.FieldByName("go115UsesCgo")
if !f.IsValid() {
f = v.FieldByName("UsesCgo")
if !f.IsValid() {
return false
}
}
addr := unsafe.Pointer(f.UnsafeAddr())
*(*bool)(addr) = true
return true
}
// ReadGo116ErrorData extracts additional information from types.Error values
// generated by Go version 1.16 and later: the error code, start position, and
// end position. If all positions are valid, start <= err.Pos <= end.
//
// If the data could not be read, the final result parameter will be false.
func ReadGo116ErrorData(err types.Error) (code ErrorCode, start, end token.Pos, ok bool) {
var data [3]int
// By coincidence all of these fields are ints, which simplifies things.
v := reflect.ValueOf(err)
for i, name := range []string{"go116code", "go116start", "go116end"} {
f := v.FieldByName(name)
if !f.IsValid() {
return 0, 0, 0, false
}
data[i] = int(f.Int())
}
return ErrorCode(data[0]), token.Pos(data[1]), token.Pos(data[2]), true
}
// NameRelativeTo returns a types.Qualifier that qualifies members of
// all packages other than pkg, using only the package name.
// (By contrast, [types.RelativeTo] uses the complete package path,
// which is often excessive.)
//
// If pkg is nil, it is equivalent to [*types.Package.Name].
func NameRelativeTo(pkg *types.Package) types.Qualifier {
return func(other *types.Package) string {
if pkg != nil && pkg == other {
return "" // same package; unqualified
}
return other.Name()
}
}
// A NamedOrAlias is a [types.Type] that is named (as
// defined by the spec) and capable of bearing type parameters: it
// abstracts aliases ([types.Alias]) and defined types
// ([types.Named]).
//
// Every type declared by an explicit "type" declaration is a
// NamedOrAlias. (Built-in type symbols may additionally
// have type [types.Basic], which is not a NamedOrAlias,
// though the spec regards them as "named".)
//
// NamedOrAlias cannot expose the Origin method, because
// [types.Alias.Origin] and [types.Named.Origin] have different
// (covariant) result types; use [Origin] instead.
type NamedOrAlias interface {
types.Type
Obj() *types.TypeName
}
// TypeParams is a light shim around t.TypeParams().
// (go/types.Alias).TypeParams requires >= 1.23.
func TypeParams(t NamedOrAlias) *types.TypeParamList {
switch t := t.(type) {
case *types.Alias:
return aliases.TypeParams(t)
case *types.Named:
return t.TypeParams()
}
return nil
}
// TypeArgs is a light shim around t.TypeArgs().
// (go/types.Alias).TypeArgs requires >= 1.23.
func TypeArgs(t NamedOrAlias) *types.TypeList {
switch t := t.(type) {
case *types.Alias:
return aliases.TypeArgs(t)
case *types.Named:
return t.TypeArgs()
}
return nil
}
// Origin returns the generic type of the Named or Alias type t if it
// is instantiated, otherwise it returns t.
func Origin(t NamedOrAlias) NamedOrAlias {
switch t := t.(type) {
case *types.Alias:
return aliases.Origin(t)
case *types.Named:
return t.Origin()
}
return t
}