// pkgString returns a string representation of a package's exported interface.
func pkgString(pkg *types.Package) string {
var buf bytes.Buffer
fmt.Fprintf(&buf, "package %s\n", pkg.Name())
scope := pkg.Scope()
for _, name := range scope.Names() {
if exported(name) {
obj := scope.Lookup(name)
buf.WriteString(obj.String())
switch obj := obj.(type) {
case *types.Const:
// For now only print constant values if they are not float
// or complex. This permits comparing go/types results with
// gc-generated gcimported package interfaces.
info := obj.Type().Underlying().(*types.Basic).Info()
if info&types.IsFloat == 0 && info&types.IsComplex == 0 {
fmt.Fprintf(&buf, " = %s", obj.Val())
}
case *types.TypeName:
// Print associated methods.
// Basic types (e.g., unsafe.Pointer) have *types.Basic
// type rather than *types.Named; so we need to check.
if typ, _ := obj.Type().(*types.Named); typ != nil {
if n := typ.NumMethods(); n > 0 {
// Sort methods by name so that we get the
// same order independent of whether the
// methods got imported or coming directly
// for the source.
// TODO(gri) This should probably be done
// in go/types.
list := make([]*types.Func, n)
for i := 0; i < n; i++ {
list[i] = typ.Method(i)
}
sort.Sort(byName(list))
buf.WriteString("\nmethods (\n")
for _, m := range list {
fmt.Fprintf(&buf, "\t%s\n", m)
}
buf.WriteString(")")
}
}
}
buf.WriteByte('\n')
}
}
return buf.String()
}
func (p *exporter) pkg(pkg *types.Package) {
if trace {
p.tracef("package { ")
defer p.tracef("} ")
}
if pkg == nil {
panic("unexpected nil pkg")
}
// if the package was seen before, write its index (>= 0)
if i, ok := p.pkgIndex[pkg]; ok {
p.int(i)
return
}
p.pkgIndex[pkg] = len(p.pkgIndex)
// otherwise, write the package tag (< 0) and package data
p.int(packageTag)
p.string(pkg.Name())
p.string(pkg.Path())
}
// ExportData serializes the interface (exported package objects)
// of package pkg and returns the corresponding data. The export
// format is described elsewhere (TODO).
func ExportData(pkg *types.Package) []byte {
p := exporter{
data: append([]byte(magic), format()),
pkgIndex: make(map[*types.Package]int),
typIndex: make(map[types.Type]int),
}
// populate typIndex with predeclared types
for _, t := range predeclared {
p.typIndex[t] = len(p.typIndex)
}
if trace {
p.tracef("export %s\n", pkg.Name())
defer p.tracef("\n")
}
p.string(version)
p.pkg(pkg)
// collect exported objects from package scope
var list []types.Object
scope := pkg.Scope()
for _, name := range scope.Names() {
if exported(name) {
list = append(list, scope.Lookup(name))
}
}
// write objects
p.int(len(list))
for _, obj := range list {
p.obj(obj)
}
return p.data
}
func testExportImport(t *testing.T, pkg0 *types.Package, path string) (size, gcsize int) {
data := ExportData(pkg0)
size = len(data)
imports := make(map[string]*types.Package)
n, pkg1, err := ImportData(imports, data)
if err != nil {
t.Errorf("package %s: import failed: %s", pkg0.Name(), err)
return
}
if n != size {
t.Errorf("package %s: not all input data consumed", pkg0.Name())
return
}
s0 := pkgString(pkg0)
s1 := pkgString(pkg1)
if s1 != s0 {
t.Errorf("package %s: \nimport got:\n%s\nwant:\n%s\n", pkg0.Name(), s1, s0)
}
// If we have a standard library, compare also against the gcimported package.
if path == "" {
return // not std library
}
gcdata, err := gcExportData(path)
if err != nil {
if pkg0.Name() == "main" {
return // no export data present for main package
}
t.Errorf("package %s: couldn't get export data: %s", pkg0.Name(), err)
}
gcsize = len(gcdata)
imports = make(map[string]*types.Package)
pkg2, err := gcImportData(imports, gcdata, path)
if err != nil {
t.Errorf("package %s: gcimport failed: %s", pkg0.Name(), err)
return
}
s2 := pkgString(pkg2)
if s2 != s0 {
t.Errorf("package %s: \ngcimport got:\n%s\nwant:\n%s\n", pkg0.Name(), s2, s0)
}
return
}