func (c *funcContext) varPtrName(o *types.Var) string {
if isPkgLevel(o) && o.Exported() {
return c.pkgVar(o.Pkg()) + "." + o.Name() + "$ptr"
}
name, ok := c.p.varPtrNames[o]
if !ok {
name = c.newVariableWithLevel(o.Name()+"$ptr", isPkgLevel(o))
c.p.varPtrNames[o] = name
}
return name
}
func (p *exporter) field(f *types.Var) {
// anonymous fields have "" name
name := ""
if !f.Anonymous() {
name = f.Name()
}
// qualifiedName will always emit the field package for
// anonymous fields because "" is not an exported name.
p.qualifiedName(f.Pkg(), name)
p.typ(f.Type())
}
func (tr *Transformer) matchWildcard(xobj *types.Var, y ast.Expr) bool {
name := xobj.Name()
if tr.verbose {
fmt.Fprintf(os.Stderr, "%s: wildcard %s -> %s?: ",
tr.fset.Position(y.Pos()), name, astString(tr.fset, y))
}
// Check that y is assignable to the declared type of the param.
yt := tr.info.TypeOf(y)
if yt == nil {
// y has no type.
// Perhaps it is an *ast.Ellipsis in [...]T{}, or
// an *ast.KeyValueExpr in T{k: v}.
// Clearly these pseudo-expressions cannot match a
// wildcard, but it would nice if we had a way to ignore
// the difference between T{v} and T{k:v} for structs.
return false
}
if !types.AssignableTo(yt, xobj.Type()) {
if tr.verbose {
fmt.Fprintf(os.Stderr, "%s not assignable to %s\n", yt, xobj.Type())
}
return false
}
// A wildcard matches any expression.
// If it appears multiple times in the pattern, it must match
// the same expression each time.
if old, ok := tr.env[name]; ok {
// found existing binding
tr.allowWildcards = false
r := tr.matchExpr(old, y)
if tr.verbose {
fmt.Fprintf(os.Stderr, "%t secondary match, primary was %s\n",
r, astString(tr.fset, old))
}
tr.allowWildcards = true
return r
}
if tr.verbose {
fmt.Fprintf(os.Stderr, "primary match\n")
}
tr.env[name] = y // record binding
return true
}
func (tr *Transformer) matchWildcard(xobj *types.Var, y ast.Expr) bool {
name := xobj.Name()
if tr.verbose {
fmt.Fprintf(os.Stderr, "%s: wildcard %s -> %s?: ",
tr.fset.Position(y.Pos()), name, astString(tr.fset, y))
}
// Check that y is assignable to the declared type of the param.
if yt := tr.info.TypeOf(y); !types.AssignableTo(yt, xobj.Type()) {
if tr.verbose {
fmt.Fprintf(os.Stderr, "%s not assignable to %s\n", yt, xobj.Type())
}
return false
}
// A wildcard matches any expression.
// If it appears multiple times in the pattern, it must match
// the same expression each time.
if old, ok := tr.env[name]; ok {
// found existing binding
tr.allowWildcards = false
r := tr.matchExpr(old, y)
if tr.verbose {
fmt.Fprintf(os.Stderr, "%t secondary match, primary was %s\n",
r, astString(tr.fset, old))
}
tr.allowWildcards = true
return r
}
if tr.verbose {
fmt.Fprintf(os.Stderr, "primary match\n")
}
tr.env[name] = y // record binding
return true
}
// checkStructField checks that the field renaming will not cause
// conflicts at its declaration, or ambiguity or changes to any selection.
func (r *Unexporter) checkStructField(objsToUpdate map[types.Object]string, from *types.Var, to string) {
// Check that the struct declaration is free of field conflicts,
// and field/method conflicts.
// go/types offers no easy way to get from a field (or interface
// method) to its declaring struct (or interface), so we must
// ascend the AST.
info, path, _ := r.iprog.PathEnclosingInterval(from.Pos(), from.Pos())
// path matches this pattern:
// [Ident SelectorExpr? StarExpr? Field FieldList StructType ParenExpr* ... File]
// Ascend to FieldList.
var i int
for {
if _, ok := path[i].(*ast.FieldList); ok {
break
}
i++
}
i++
tStruct := path[i].(*ast.StructType)
i++
// Ascend past parens (unlikely).
for {
_, ok := path[i].(*ast.ParenExpr)
if !ok {
break
}
i++
}
if spec, ok := path[i].(*ast.TypeSpec); ok {
// This struct is also a named type.
// We must check for direct (non-promoted) field/field
// and method/field conflicts.
named := info.Defs[spec.Name].Type()
prev, indices, _ := types.LookupFieldOrMethod(named, true, info.Pkg, to)
if len(indices) == 1 {
r.warn(from,
r.errorf(from.Pos(), "renaming this field %q to %q",
from.Name(), to),
r.errorf(prev.Pos(), "\twould conflict with this %s",
objectKind(prev)))
return // skip checkSelections to avoid redundant errors
}
} else {
// This struct is not a named type.
// We need only check for direct (non-promoted) field/field conflicts.
t := info.Types[tStruct].Type.Underlying().(*types.Struct)
for i := 0; i < t.NumFields(); i++ {
if prev := t.Field(i); prev.Name() == to {
r.warn(from,
r.errorf(from.Pos(), "renaming this field %q to %q",
from.Name(), to),
r.errorf(prev.Pos(), "\twould conflict with this field"))
return // skip checkSelections to avoid redundant errors
}
}
}
// Renaming an anonymous field requires renaming the type too. e.g.
// print(s.T) // if we rename T to U,
// type T int // this and
// var s struct {T} // this must change too.
if from.Anonymous() {
if named, ok := from.Type().(*types.Named); ok {
r.check(objsToUpdate, named.Obj(), to)
} else if named, ok := deref(from.Type()).(*types.Named); ok {
r.check(objsToUpdate, named.Obj(), to)
}
}
// Check integrity of existing (field and method) selections.
r.checkSelections(objsToUpdate, from, to)
}
func newVarFrom(p *Package, v *types.Var) *Var {
return newVar(p, v.Type(), v.Name(), v.Name(), p.getDoc("", v))
}
func (p *exporter) param(v *types.Var) {
p.string(v.Name())
p.typ(v.Type())
}