This file has a few changes compared to the go/types version:
1) syntax.Pos is used instead of token.Pos.
2) The cmpPos helper function (defined elsewhere) is used to
compare positions (syntax.Pos positions cannot be compared
directly with <=).
3) A new method Scope.Squash was added (primary difference).
f=scope.go; diff $f ../../../../go/types/$f
7c7
< package types2
---
> package types
11d10
< "cmd/compile/internal/syntax"
12a12
> "go/token"
26c26
< pos, end syntax.Pos // scope extent; may be invalid
---
> pos, end token.Pos // scope extent; may be invalid
33c33
< func NewScope(parent *Scope, pos, end syntax.Pos, comment string) *Scope {
---
> func NewScope(parent *Scope, pos, end token.Pos, comment string) *Scope {
82c82
< func (s *Scope) LookupParent(name string, pos syntax.Pos) (*Scope, Object) {
---
> func (s *Scope) LookupParent(name string, pos token.Pos) (*Scope, Object) {
84c84
< if obj := s.elems[name]; obj != nil && (!pos.IsKnown() || cmpPos(obj.scopePos(), pos) <= 0) {
---
> if obj := s.elems[name]; obj != nil && (!pos.IsValid() || obj.scopePos() <= pos) {
111,
144d110
< // Squash merges s with its parent scope p by adding all
< // objects of s to p, adding all children of s to the
< // children of p, and removing s from p's children.
< // The function f is called for each object obj in s which
< // has an object alt in p. s should be discarded after
< // having been squashed.
< func (s *Scope) Squash(err func(obj, alt Object)) {
< p := s.parent
< assert(p != nil)
< for _, obj := range s.elems {
< obj.setParent(nil)
< if alt := p.Insert(obj); alt != nil {
< err(obj, alt)
< }
< }
<
< j := -1 // index of s in p.children
< for i, ch := range p.children {
< if ch == s {
< j = i
< break
< }
< }
< assert(j >= 0)
< k := len(p.children) - 1
< p.children[j] = p.children[k]
< p.children = p.children[:k]
<
< p.children = append(p.children, s.children...)
<
< s.children = nil
< s.elems = nil
< }
<
149,
150c115,116
< func (s *Scope) Pos() syntax.Pos { return s.pos }
< func (s *Scope) End() syntax.Pos { return s.end }
---
> func (s *Scope) Pos() token.Pos { return s.pos }
> func (s *Scope) End() token.Pos { return s.end }
155,
156c121,122
< func (s *Scope) Contains(pos syntax.Pos) bool {
< return cmpPos(s.pos, pos) <= 0 && cmpPos(pos, s.end) < 0
---
> func (s *Scope) Contains(pos token.Pos) bool {
> return s.pos <= pos && pos < s.end
164c130
< func (s *Scope) Innermost(pos syntax.Pos) *Scope {
---
> func (s *Scope) Innermost(pos token.Pos) *Scope {
Change-Id: If6c459f45dae8980ffb3a902a46b1700e9b55dc7
Reviewed-on: https://go-review.googlesource.com/c/go/+/265700
Trust: Robert Griesemer <gri@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>