func isStringer(obj types.Object) bool {
switch obj := obj.(type) {
case *types.Func:
if obj.Name() != "String" {
return false
}
sig, ok := obj.Type().(*types.Signature)
if !ok {
return false
}
if sig.Recv() == nil {
return false
}
if sig.Params().Len() != 0 {
return false
}
res := sig.Results()
if res.Len() != 1 {
return false
}
ret := res.At(0).Type()
if ret != types.Universe.Lookup("string").Type() {
return false
}
return true
default:
return false
}
return false
}
// lookup returns the address of the named variable identified by obj
// that is local to function f or one of its enclosing functions.
// If escaping, the reference comes from a potentially escaping pointer
// expression and the referent must be heap-allocated.
//
func (f *Function) lookup(obj types.Object, escaping bool) Value {
if v, ok := f.objects[obj]; ok {
if alloc, ok := v.(*Alloc); ok && escaping {
alloc.Heap = true
}
return v // function-local var (address)
}
// Definition must be in an enclosing function;
// plumb it through intervening closures.
if f.parent == nil {
panic("no Value for type.Object " + obj.Name())
}
outer := f.parent.lookup(obj, true) // escaping
v := &FreeVar{
name: obj.Name(),
typ: outer.Type(),
pos: outer.Pos(),
outer: outer,
parent: f,
}
f.objects[obj] = v
f.FreeVars = append(f.FreeVars, v)
return v
}
func (r *Unexporter) selectionConflict(objsToUpdate map[types.Object]string, from types.Object, to string, delta int, syntax *ast.SelectorExpr, obj types.Object) {
rename := r.errorf(from.Pos(), "renaming this %s %q to %q",
objectKind(from), from.Name(), to)
switch {
case delta < 0:
// analogous to sub-block conflict
r.warn(from, rename,
r.errorf(syntax.Sel.Pos(),
"\twould change the referent of this selection"),
r.errorf(obj.Pos(), "\tof this %s", objectKind(obj)))
case delta == 0:
// analogous to same-block conflict
r.warn(from, rename,
r.errorf(syntax.Sel.Pos(),
"\twould make this reference ambiguous"),
r.errorf(obj.Pos(), "\twith this %s", objectKind(obj)))
case delta > 0:
// analogous to super-block conflict
r.warn(from, rename,
r.errorf(syntax.Sel.Pos(),
"\twould shadow this selection"),
r.errorf(obj.Pos(), "\tof the %s declared here",
objectKind(obj)))
}
}
func formatMember(obj types.Object, maxname int) string {
var buf bytes.Buffer
fmt.Fprintf(&buf, "%-5s %-*s", tokenOf(obj), maxname, obj.Name())
switch obj := obj.(type) {
case *types.Const:
fmt.Fprintf(&buf, " %s = %s", types.TypeString(obj.Pkg(), obj.Type()), obj.Val().String())
case *types.Func:
fmt.Fprintf(&buf, " %s", types.TypeString(obj.Pkg(), obj.Type()))
case *types.TypeName:
// Abbreviate long aggregate type names.
var abbrev string
switch t := obj.Type().Underlying().(type) {
case *types.Interface:
if t.NumMethods() > 1 {
abbrev = "interface{...}"
}
case *types.Struct:
if t.NumFields() > 1 {
abbrev = "struct{...}"
}
}
if abbrev == "" {
fmt.Fprintf(&buf, " %s", types.TypeString(obj.Pkg(), obj.Type().Underlying()))
} else {
fmt.Fprintf(&buf, " %s", abbrev)
}
case *types.Var:
fmt.Fprintf(&buf, " %s", types.TypeString(obj.Pkg(), obj.Type()))
}
return buf.String()
}
// memberFromObject populates package pkg with a member for the
// typechecker object obj.
//
// For objects from Go source code, syntax is the associated syntax
// tree (for funcs and vars only); it will be used during the build
// phase.
//
func memberFromObject(pkg *Package, obj types.Object, syntax ast.Node) {
name := obj.Name()
switch obj := obj.(type) {
case *types.TypeName:
pkg.Members[name] = &Type{
object: obj,
pkg: pkg,
}
case *types.Const:
c := &NamedConst{
object: obj,
Value: NewConst(obj.Val(), obj.Type()),
pkg: pkg,
}
pkg.values[obj] = c.Value
pkg.Members[name] = c
case *types.Var:
g := &Global{
Pkg: pkg,
name: name,
object: obj,
typ: types.NewPointer(obj.Type()), // address
pos: obj.Pos(),
}
pkg.values[obj] = g
pkg.Members[name] = g
case *types.Func:
sig := obj.Type().(*types.Signature)
if sig.Recv() == nil && name == "init" {
pkg.ninit++
name = fmt.Sprintf("init#%d", pkg.ninit)
}
fn := &Function{
name: name,
object: obj,
Signature: sig,
syntax: syntax,
pos: obj.Pos(),
Pkg: pkg,
Prog: pkg.Prog,
}
if syntax == nil {
fn.Synthetic = "loaded from gc object file"
}
pkg.values[obj] = fn
if sig.Recv() == nil {
pkg.Members[name] = fn // package-level function
}
default: // (incl. *types.Package)
panic("unexpected Object type: " + obj.String())
}
}
func (f *Function) addParamObj(obj types.Object) *Parameter {
name := obj.Name()
if name == "" {
name = fmt.Sprintf("arg%d", len(f.Params))
}
param := f.addParam(name, obj.Type(), obj.Pos())
param.object = obj
return param
}
// addSpilledParam declares a parameter that is pre-spilled to the
// stack; the function body will load/store the spilled location.
// Subsequent lifting will eliminate spills where possible.
//
func (f *Function) addSpilledParam(obj types.Object) {
param := f.addParamObj(obj)
spill := &Alloc{Comment: obj.Name()}
spill.setType(types.NewPointer(obj.Type()))
spill.setPos(obj.Pos())
f.objects[obj] = spill
f.Locals = append(f.Locals, spill)
f.emit(spill)
f.emit(&Store{Addr: spill, Val: param})
}
func (sym *symtab) addSymbol(obj types.Object) {
fn := types.ObjectString(obj, nil)
n := obj.Name()
pkg := obj.Pkg()
id := n
if pkg != nil {
id = pkg.Name() + "_" + n
}
switch obj.(type) {
case *types.Const:
sym.syms[fn] = &symbol{
gopkg: pkg,
goobj: obj,
kind: skConst,
id: id,
goname: n,
cgoname: "cgo_const_" + id,
cpyname: "cpy_const_" + id,
}
sym.addType(obj, obj.Type())
case *types.Var:
sym.syms[fn] = &symbol{
gopkg: pkg,
goobj: obj,
kind: skVar,
id: id,
goname: n,
cgoname: "cgo_var_" + id,
cpyname: "cpy_var_" + id,
}
sym.addType(obj, obj.Type())
case *types.Func:
sym.syms[fn] = &symbol{
gopkg: pkg,
goobj: obj,
kind: skFunc,
id: id,
goname: n,
cgoname: "cgo_func_" + id,
cpyname: "cpy_func_" + id,
}
sig := obj.Type().Underlying().(*types.Signature)
sym.processTuple(sig.Params())
sym.processTuple(sig.Results())
case *types.TypeName:
sym.addType(obj, obj.Type())
default:
panic(fmt.Errorf("gopy: handled object [%#v]", obj))
}
}
func (r *resolver) defineObject(b *Block, name string, obj types.Object) {
if obj.Name() == "_" {
return
}
i := len(b.bindings)
b.bindings = append(b.bindings, obj)
b.index[name] = i
if trace {
logf("def %s = %s in %s\n", name, types.ObjectString(obj, r.qualifier), b)
}
r.result.Defs[obj] = b
}
func newObject(obj types.Object, sel *types.Selection) (*Object, error) {
// WARN: Dev only
if sel != nil {
return newSelector(sel)
}
o := &Object{
Name: obj.Name(),
pos: obj.Pos(),
}
o.setPkg(obj.Pkg())
switch typ := obj.(type) {
case *types.PkgName:
o.ObjType = Package
if p := typ.Imported(); p != nil {
o.setPkg(p)
}
case *types.Const:
o.ObjType = Const
case *types.TypeName:
o.ObjType = TypeName
case *types.Var:
o.ObjType = Var
o.IsField = typ.IsField()
if t, ok := derefType(typ.Type()).(*types.Named); ok {
o.ObjType = TypeName
// WARN: This looks wrong
o.IsField = false
if obj := t.Obj(); obj != nil {
o.Name = obj.Name()
o.setPkg(obj.Pkg())
o.pos = obj.Pos() // WARN
}
}
case *types.Func:
if sig := typ.Type().(*types.Signature); sig != nil {
o.ObjType = Func
} else {
switch r := derefType(sig.Recv().Type()).(type) {
case *types.Named:
o.ObjType = Method
o.setParent(r.Obj())
case *types.Interface:
o.ObjType = Interface
default:
// This should never happen
}
}
default:
// TODO: log type
o.ObjType = Bad
}
return o, nil
}
func (e *Export) checkInLexicalScope(from types.Object, to string) {
info := e.u.pkgInfo
lexinfo := lexical.Structure(e.u.prog.Fset, info.Pkg, &info.Info, info.Files)
b := lexinfo.Defs[from] // the block defining the 'from' object
if b != nil {
to, toBlock := b.Lookup(to)
if toBlock == b {
e.Conflicting = true
return // same-block conflict
} else if toBlock != nil {
for _, ref := range lexinfo.Refs[to] {
if obj, _ := ref.Env.Lookup(from.Name()); obj == from {
e.Conflicting = true
return // super-block conflict
}
}
}
}
// Check for sub-block conflict.
// Is there an intervening definition of r.to between
// the block defining 'from' and some reference to it?
for _, ref := range lexinfo.Refs[from] {
_, fromBlock := ref.Env.Lookup(from.Name())
fromDepth := fromBlock.Depth()
to, toBlock := ref.Env.Lookup(to)
if to != nil {
// sub-block conflict
if toBlock.Depth() > fromDepth {
e.Conflicting = true
return
}
}
}
// Renaming a type that is used as an embedded field
// requires renaming the field too. e.g.
// type T int // if we rename this to U..
// var s struct {T}
// print(s.T) // ...this must change too
if _, ok := from.(*types.TypeName); ok {
for id, obj := range info.Uses {
if obj == from {
if field := info.Defs[id]; field != nil {
e.check(field, to)
}
}
}
}
}
func (p *exporter) obj(obj types.Object) {
if trace {
p.tracef("object %s {\n", obj.Name())
defer p.tracef("}\n")
}
switch obj := obj.(type) {
case *types.Const:
p.int(constTag)
p.string(obj.Name())
p.typ(obj.Type())
p.value(obj.Val())
case *types.TypeName:
p.int(typeTag)
// name is written by corresponding named type
p.typ(obj.Type().(*types.Named))
case *types.Var:
p.int(varTag)
p.string(obj.Name())
p.typ(obj.Type())
case *types.Func:
p.int(funcTag)
p.string(obj.Name())
p.typ(obj.Type())
default:
panic(fmt.Sprintf("unexpected object type %T", obj))
}
}
func printObject(u *unexporter.Unexporter, o types.Object) {
var objName string
if simpleNamesFlag {
objName = o.Name()
} else {
objName = o.String()
}
if showFilename {
pos := u.PositionForObject(o)
fmt.Printf("%s:%d:%d: %s\n", pos.Filename, pos.Line, pos.Column, objName)
} else {
fmt.Println(objName)
}
}
func (r *renamer) checkExport(id *ast.Ident, pkg *types.Package, from types.Object) bool {
// Reject cross-package references if r.to is unexported.
// (Such references may be qualified identifiers or field/method
// selections.)
if !ast.IsExported(r.to) && pkg != from.Pkg() {
r.errorf(from.Pos(),
"renaming this %s %q to %q would make it unexported",
objectKind(from), from.Name(), r.to)
r.errorf(id.Pos(), "\tbreaking references from packages such as %q",
pkg.Path())
return false
}
return true
}
func getKey(obj types.Object) object {
if obj == nil {
return object{}
}
pkg := obj.Pkg()
pkgPath := ""
if pkg != nil {
pkgPath = pkg.Path()
}
return object{
pkgPath: pkgPath,
name: obj.Name(),
}
}
func (p *printer) printObj(obj types.Object) {
p.print(obj.Name())
typ, basic := obj.Type().Underlying().(*types.Basic)
if basic && typ.Info()&types.IsUntyped != 0 {
// don't write untyped types
} else {
p.print(" ")
p.writeType(p.pkg, obj.Type())
}
if obj, ok := obj.(*types.Const); ok {
floatFmt := basic && typ.Info()&(types.IsFloat|types.IsComplex) != 0
p.print(" = ")
p.print(valString(obj.Val(), floatFmt))
}
}
func (g *Grapher) makeDefInfo(obj types.Object) (*DefKey, *defInfo, error) {
switch obj := obj.(type) {
case *types.Builtin:
return &DefKey{"builtin", []string{obj.Name()}}, &defInfo{pkgscope: false, exported: true}, nil
case *types.Nil:
return &DefKey{"builtin", []string{"nil"}}, &defInfo{pkgscope: false, exported: true}, nil
case *types.TypeName:
if basic, ok := obj.Type().(*types.Basic); ok {
return &DefKey{"builtin", []string{basic.Name()}}, &defInfo{pkgscope: false, exported: true}, nil
}
if obj.Name() == "error" {
return &DefKey{"builtin", []string{obj.Name()}}, &defInfo{pkgscope: false, exported: true}, nil
}
case *types.PkgName:
return &DefKey{obj.Imported().Path(), []string{}}, &defInfo{pkgscope: false, exported: true}, nil
case *types.Const:
var pkg string
if obj.Pkg() == nil {
pkg = "builtin"
} else {
pkg = obj.Pkg().Path()
}
if obj.Val().Kind() == exact.Bool && pkg == "builtin" {
return &DefKey{pkg, []string{obj.Name()}}, &defInfo{pkgscope: false, exported: true}, nil
}
}
if obj.Pkg() == nil {
// builtin
return &DefKey{"builtin", []string{obj.Name()}}, &defInfo{pkgscope: false, exported: true}, nil
}
path := g.path(obj)
// Handle the case where a dir has 2 main packages that are not
// intended to be compiled together and have overlapping def
// paths. Prefix the def path with the filename.
if obj.Pkg().Name() == "main" {
p := g.program.Fset.Position(obj.Pos())
path = append([]string{filepath.Base(p.Filename)}, path...)
}
return &DefKey{obj.Pkg().Path(), path}, &defInfo{pkgscope: g.pkgscope[obj], exported: g.exported[obj]}, nil
}
// getDoc returns the doc string associated with types.Object
func (p *Package) getDoc(o types.Object) string {
n := o.Name()
switch o.(type) {
case *types.Const:
for _, c := range p.doc.Consts {
for _, cn := range c.Names {
if n == cn {
return c.Doc
}
}
}
case *types.Var:
for _, v := range p.doc.Vars {
for _, vn := range v.Names {
if n == vn {
return v.Doc
}
}
}
case *types.Func:
for _, f := range p.doc.Funcs {
if n == f.Name {
return f.Doc
}
}
case *types.TypeName:
for _, t := range p.doc.Types {
if n == t.Name {
return t.Doc
}
}
default:
// TODO(sbinet)
panic(fmt.Errorf("not yet supported: %v (%T)", o, o))
}
return ""
}
func (c *funcContext) objectName(o types.Object) string {
if isPkgLevel(o) {
c.p.dependencies[o] = true
if o.Pkg() != c.p.Pkg || (isVarOrConst(o) && o.Exported()) {
return c.pkgVar(o.Pkg()) + "." + o.Name()
}
}
name, ok := c.p.objectNames[o]
if !ok {
name = c.newVariableWithLevel(o.Name(), isPkgLevel(o))
c.p.objectNames[o] = name
}
if v, ok := o.(*types.Var); ok && c.p.escapingVars[v] {
return name + "[0]"
}
return name
}
// ssaValueForIdent returns the ssa.Value for the ast.Ident whose path
// to the root of the AST is path. isAddr reports whether the
// ssa.Value is the address denoted by the ast.Ident, not its value.
//
func ssaValueForIdent(prog *ssa.Program, qinfo *loader.PackageInfo, obj types.Object, path []ast.Node) (value ssa.Value, isAddr bool, err error) {
switch obj := obj.(type) {
case *types.Var:
pkg := prog.Package(qinfo.Pkg)
pkg.Build()
if v, addr := prog.VarValue(obj, pkg, path); v != nil {
return v, addr, nil
}
return nil, false, fmt.Errorf("can't locate SSA Value for var %s", obj.Name())
case *types.Func:
fn := prog.FuncValue(obj)
if fn == nil {
return nil, false, fmt.Errorf("%s is an interface method", obj)
}
// TODO(adonovan): there's no point running PTA on a *Func ident.
// Eliminate this feature.
return fn, false, nil
}
panic(obj)
}
// checkInPackageBlock performs safety checks for renames of
// func/var/const/type objects in the package block.
func (r *renamer) checkInPackageBlock(from types.Object) {
// Check that there are no references to the name from another
// package if the renaming would make it unexported.
if ast.IsExported(from.Name()) && !ast.IsExported(r.to) {
for pkg, info := range r.packages {
if pkg == from.Pkg() {
continue
}
if id := someUse(info, from); id != nil &&
!r.checkExport(id, pkg, from) {
break
}
}
}
info := r.packages[from.Pkg()]
// Check that in the package block, "init" is a function, and never referenced.
if r.to == "init" {
kind := objectKind(from)
if kind == "func" {
// Reject if intra-package references to it exist.
for id, obj := range info.Uses {
if obj == from {
r.errorf(from.Pos(),
"renaming this func %q to %q would make it a package initializer",
from.Name(), r.to)
r.errorf(id.Pos(), "\tbut references to it exist")
break
}
}
} else {
r.errorf(from.Pos(), "you cannot have a %s at package level named %q",
kind, r.to)
}
}
// Check for conflicts between package block and all file blocks.
for _, f := range info.Files {
fileScope := info.Info.Scopes[f]
b, prev := fileScope.LookupParent(r.to, token.NoPos)
if b == fileScope {
r.errorf(from.Pos(), "renaming this %s %q to %q would conflict",
objectKind(from), from.Name(), r.to)
r.errorf(prev.Pos(), "\twith this %s",
objectKind(prev))
return // since checkInPackageBlock would report redundant errors
}
}
// Check for conflicts in lexical scope.
if from.Exported() {
for _, info := range r.packages {
r.checkInLexicalScope(from, info)
}
} else {
r.checkInLexicalScope(from, info)
}
}
func (r *renamer) selectionConflict(from types.Object, delta int, syntax *ast.SelectorExpr, obj types.Object) {
r.errorf(from.Pos(), "renaming this %s %q to %q",
objectKind(from), from.Name(), r.to)
switch {
case delta < 0:
// analogous to sub-block conflict
r.errorf(syntax.Sel.Pos(),
"\twould change the referent of this selection")
r.errorf(obj.Pos(), "\tto this %s", objectKind(obj))
case delta == 0:
// analogous to same-block conflict
r.errorf(syntax.Sel.Pos(),
"\twould make this reference ambiguous")
r.errorf(obj.Pos(), "\twith this %s", objectKind(obj))
case delta > 0:
// analogous to super-block conflict
r.errorf(syntax.Sel.Pos(),
"\twould shadow this selection")
r.errorf(obj.Pos(), "\tto the %s declared here",
objectKind(obj))
}
}
func checkNilFuncComparison(f *File, node ast.Node) {
e := node.(*ast.BinaryExpr)
// Only want == or != comparisons.
if e.Op != token.EQL && e.Op != token.NEQ {
return
}
// Only want comparisons with a nil identifier on one side.
var e2 ast.Expr
switch {
case f.isNil(e.X):
e2 = e.Y
case f.isNil(e.Y):
e2 = e.X
default:
return
}
// Only want identifiers or selector expressions.
var obj types.Object
switch v := e2.(type) {
case *ast.Ident:
obj = f.pkg.uses[v]
case *ast.SelectorExpr:
obj = f.pkg.uses[v.Sel]
default:
return
}
// Only want functions.
if _, ok := obj.(*types.Func); !ok {
return
}
f.Badf(e.Pos(), "comparison of function %v %v nil is always %v", obj.Name(), e.Op, e.Op == token.NEQ)
}
// checkInPackageBlock performs safety checks for renames of
// func/var/const/type objects in the package block.
func (r *Unexporter) checkInPackageBlock(objsToUpdate map[types.Object]string, from types.Object, to string) {
// Check that there are no references to the name from another
// package if the renaming would make it unexported.
if ast.IsExported(from.Name()) && !ast.IsExported(to) {
for pkg, info := range r.packages {
if pkg == from.Pkg() {
continue
}
if id := someUse(info, from); id != nil &&
!r.checkExport(id, pkg, from, to) {
break
}
}
}
info := r.packages[from.Pkg()]
lexinfo := r.lexInfo(info)
// Check that in the package block, "init" is a function, and never referenced.
if to == "init" {
kind := objectKind(from)
if kind == "func" {
// Reject if intra-package references to it exist.
if refs := lexinfo.Refs[from]; len(refs) > 0 {
r.warn(from,
r.errorf(from.Pos(),
"renaming this func %q to %q would make it a package initializer",
from.Name(), to),
r.errorf(refs[0].Id.Pos(), "\tbut references to it exist"))
}
} else {
r.warn(from, r.errorf(from.Pos(), "you cannot have a %s at package level named %q",
kind, to))
}
}
// Check for conflicts between package block and all file blocks.
for _, f := range info.Files {
if prev, b := lexinfo.Blocks[f].Lookup(to); b == lexinfo.Blocks[f] {
r.warn(from,
r.errorf(from.Pos(), "renaming this %s %q to %q would conflict",
objectKind(from), from.Name(), to),
r.errorf(prev.Pos(), "\twith this %s",
objectKind(prev)))
return // since checkInPackageBlock would report redundant errors
}
}
// Check for conflicts in lexical scope.
if from.Exported() {
for _, info := range r.packages {
r.checkInLexicalScope(objsToUpdate, from, to, info)
}
} else {
r.checkInLexicalScope(objsToUpdate, from, to, info)
}
}
func (g *Grapher) path(obj types.Object) (path []string) {
if path, present := g.paths[obj]; present {
return path
}
var scope *types.Scope
pkgInfo, astPath, _ := g.program.PathEnclosingInterval(obj.Pos(), obj.Pos())
if astPath != nil {
for _, node := range astPath {
if s, hasScope := pkgInfo.Scopes[node]; hasScope {
scope = s
}
}
}
if scope == nil {
scope = obj.Parent()
}
if scope == nil {
// TODO(sqs): make this actually handle cases like the one described in
// https://github.com/sourcegraph/sourcegraph.com/issues/218
log.Printf("Warning: no scope for object %s at pos %s", obj.String(), g.program.Fset.Position(obj.Pos()))
return nil
}
prefix, hasPath := g.scopePaths[scope]
if !hasPath {
panic("no scope path for scope " + scope.String())
}
path = append([]string{}, prefix...)
p := g.program.Fset.Position(obj.Pos())
path = append(path, obj.Name()+uniqID(p))
return path
panic("no scope node for object " + obj.String())
}
// checkSelection checks that all uses and selections that resolve to
// the specified object would continue to do so after the renaming.
func (e *Export) checkSelections(from types.Object, to string) {
info := e.u.pkgInfo
if id := someUse(info, from); id != nil {
e.Conflicting = true
return
}
for _, sel := range info.Selections {
if sel.Obj() == from {
if obj, indices, _ := types.LookupFieldOrMethod(sel.Recv(), true, from.Pkg(), to); obj != nil {
// Renaming this existing selection of
// 'from' may block access to an existing
// type member named 'to'.
delta := len(indices) - len(sel.Index())
if delta > 0 {
continue // no ambiguity
}
e.Conflicting = true
return
}
} else if sel.Obj().Name() == to {
if obj, indices, _ := types.LookupFieldOrMethod(sel.Recv(), true, from.Pkg(), from.Name()); obj == from {
// Renaming 'from' may cause this existing
// selection of the name 'to' to change
// its meaning.
delta := len(indices) - len(sel.Index())
if delta > 0 {
continue // no ambiguity
}
e.Conflicting = true
return
}
}
}
}
func wholePath(obj types.Object, path string, prog *loader.Program) string {
if v, ok := obj.(*types.Var); ok && v.IsField() {
structName := getDeclareStructOrInterface(prog, v)
return fmt.Sprintf("(\"%s\".%s).%s", path, structName, obj.Name())
} else if f, ok := obj.(*types.Func); ok {
if r := recv(f); r != nil {
return fmt.Sprintf("(\"%s\".%s).%s", r.Pkg().Path(), typeName(r.Type()), obj.Name())
}
}
return fmt.Sprintf("\"%s\".%s", path, obj.Name())
}
func newFuncFrom(p *Package, parent string, obj types.Object, sig *types.Signature) (Func, error) {
haserr := false
res := sig.Results()
var ret types.Type
switch res.Len() {
case 2:
if !isErrorType(res.At(1).Type()) {
return Func{}, fmt.Errorf(
"bind: second result value must be of type error: %s",
obj,
)
}
haserr = true
ret = res.At(0).Type()
case 1:
if isErrorType(res.At(0).Type()) {
haserr = true
ret = nil
} else {
ret = res.At(0).Type()
}
case 0:
ret = nil
default:
return Func{}, fmt.Errorf("bind: too many results to return: %v", obj)
}
id := obj.Pkg().Name() + "_" + obj.Name()
if parent != "" {
id = obj.Pkg().Name() + "_" + parent + "_" + obj.Name()
}
return Func{
pkg: p,
sig: newSignatureFrom(p, sig),
typ: obj.Type(),
name: obj.Name(),
id: id,
doc: p.getDoc(parent, obj),
ret: ret,
err: haserr,
}, nil
}
func isAccessibleFrom(obj types.Object, pkg *types.Package) bool {
return ast.IsExported(obj.Name()) || obj.Pkg() == pkg
}
func isPackageLevel(obj types.Object) bool {
return obj.Pkg().Scope().Lookup(obj.Name()) == obj
}