go/types, types2: implement Alias proposal (export API)

[gostls13.git] / src / go / types / api.go

diff --git a/src/go/types/api.go b/src/go/types/api.go
index 33633ea83cb3ee0542360db30dec7aa75fe12f3f..6635253fdfdd37f07a5f97293be36bad2b282bd8 100644 (file)
--- a/src/go/types/api.go
+++ b/src/go/types/api.go
@@ -286,11 +286,12 @@ type Info struct {
        // appear in this list.
        InitOrder []*Initializer
 
-       // _FileVersions maps a file to the file's Go version string.
-       // If the file doesn't specify a version and Config.GoVersion
-       // is not given, the reported version is the empty string.
-       // TODO(gri) should this be "go0.0" instead in that case?
-       _FileVersions map[*ast.File]string
+       // FileVersions maps a file to its Go version string.
+       // If the file doesn't specify a version, the reported
+       // string is Config.GoVersion.
+       // Version strings begin with “go”, like “go1.21”, and
+       // are suitable for use with the [go/version] package.
+       FileVersions map[*ast.File]string
 }
 
 func (info *Info) recordTypes() bool {
@@ -325,6 +326,23 @@ func (info *Info) ObjectOf(id *ast.Ident) Object {
        return info.Uses[id]
 }
 
+// PkgNameOf returns the local package name defined by the import,
+// or nil if not found.
+//
+// For dot-imports, the package name is ".".
+//
+// Precondition: the Defs and Implicts maps are populated.
+func (info *Info) PkgNameOf(imp *ast.ImportSpec) *PkgName {
+       var obj Object
+       if imp.Name != nil {
+               obj = info.Defs[imp.Name]
+       } else {
+               obj = info.Implicits[imp]
+       }
+       pkgname, _ := obj.(*PkgName)
+       return pkgname
+}
+
 // TypeAndValue reports the type and value (for constants)
 // of the corresponding expression.
 type TypeAndValue struct {