go/types: fix error message for embedded non-interface types in interfaces
Fixes #10979.
Change-Id: Iac25645ba8181a56a75ddfcd29ff6d64c15c4f57
Reviewed-on: https://go-review.googlesource.com/10466
Reviewed-by: Alan Donovan <adonovan@google.com>
diff --git a/src/go/types/testdata/issues.src b/src/go/types/testdata/issues.src
index d08e0fd..595a634 100644
--- a/src/go/types/testdata/issues.src
+++ b/src/go/types/testdata/issues.src
@@ -71,3 +71,27 @@
append_(f0(), f1()... /* ERROR cannot use */ )
append_(f0(), f2()... /* ERROR cannot use */ )
}
+
+// Check that embedding a non-interface type in an interface results in a good error message.
+func issue10979() {
+ type _ interface {
+ int /* ERROR int is not an interface */
+ }
+ type T struct{}
+ type _ interface {
+ T /* ERROR T is not an interface */
+ }
+ type _ interface {
+ nosuchtype /* ERROR undeclared name: nosuchtype */
+ }
+ type _ interface {
+ fmt /* ERROR Nosuchtype not declared by package fmt */ .Nosuchtype
+ }
+ type _ interface {
+ nosuchpkg /* ERROR undeclared name: nosuchpkg */ .Nosuchtype
+ }
+ type I interface {
+ I /* ERROR I\.m \(value of type func\(I\)\) is not a type */ .m
+ m()
+ }
+}
diff --git a/src/go/types/typexpr.go b/src/go/types/typexpr.go
index f4e4dcb..3fc1574 100644
--- a/src/go/types/typexpr.go
+++ b/src/go/types/typexpr.go
@@ -525,20 +525,14 @@
for _, e := range embedded {
pos := e.Pos()
typ := check.typExpr(e, nil, path)
+ // Determine underlying embedded (possibly incomplete) type
+ // by following its forward chain.
named, _ := typ.(*Named)
- if named == nil {
- if typ != Typ[Invalid] {
- check.invalidAST(pos, "%s is not named type", typ)
- }
- continue
- }
- // determine underlying (possibly incomplete) type
- // by following its forward chain
- u := underlying(named)
- embed, _ := u.(*Interface)
+ under := underlying(named)
+ embed, _ := under.(*Interface)
if embed == nil {
- if u != Typ[Invalid] {
- check.errorf(pos, "%s is not an interface", named)
+ if typ != Typ[Invalid] {
+ check.errorf(pos, "%s is not an interface", typ)
}
continue
}
