if origin == nil {
		return errors.New("nil Origin")
	}

	// Ensure that the Origin actually includes enough fields to resolve the query.
	// If we got the previous Origin data from a proxy, it may be missing something
	// that we would have needed to resolve the query directly from the repo.
	switch {
	case origin.RepoSum != "":

				t.Fatal(err)
			}
			if !reflect.DeepEqual(info, tt.info) {
				t.Errorf("Latest: incorrect info\nhave %+v (origin %+v)\nwant %+v (origin %+v)", info, info.Origin, tt.info, tt.info.Origin)
			}
		}
	}

	for _, tt := range []latestTest{
		{
			gitrepo1,
			&RevInfo{
				Origin: &Origin{
					VCS:  "git",
					URL:  gitrepo1,
					Ref:  "HEAD",
					Hash: "ede458df7cd0fdca520df19a33158086a8a68e81",

//
// [underlying type]: https://go.dev/ref/spec#Underlying_types.
func (a *Alias) Underlying() Type { return unalias(a).Underlying() }

// Origin returns the generic Alias type of which a is an instance.
// If a is not an instance of a generic alias, Origin returns a.
func (a *Alias) Origin() *Alias { return a.orig }

// TypeParams returns the type parameters of the alias type a, or nil.

			}
			// String and Type are expected to differ.
		})
	}
}

func originObject(obj Object) Object {
	switch obj := obj.(type) {
	case *Var:
		return obj.Origin()
	case *Func:
		return obj.Origin()
	}
	return obj
}

func TestImplements(t *testing.T) {
	const src = `
package p

type EmptyIface interface{}

type I interface {
	m()
}

				// We have a cycle. If t != t.Origin() then t is an instance of
				// the generic type t.Origin(). Because t is in the nest, t must
				// occur within the definition (RHS) of the generic type t.Origin(),
				// directly or indirectly, after expansion of the RHS.
				// Therefore t.Origin() must be invalid, no matter how it is
				// instantiated since the instantiation t of t.Origin() happens

				allowedVersions = append(allowedVersions, v)
			} else if !errors.Is(err, ErrDisallowed) {
				return err
			}
		}
		versions = allowedVersions
		origin = allVersions.Origin
		return nil
	})
	return versions, origin, err
}

// previousVersion returns the tagged version of m.Path immediately prior to
// m.Version, or version "none" if no prior version is tagged.
//

	if err != nil {
		return nil, &UnknownRevisionError{Rev: rev}
	}
	info, err := r.cmd.parseStat(rev, string(out))
	if err != nil {
		return nil, err
	}
	if info.Origin == nil {
		info.Origin = new(Origin)
	}
	info.Origin.VCS = r.cmd.vcs
	info.Origin.URL = r.remote
	return info, nil
}

func (r *vcsRepo) Latest(ctx context.Context) (*RevInfo, error) {
	return r.Stat(ctx, "latest")
}

// instantiated types, this is same as the type name of the origin type.
func (t *Named) Obj() *TypeName {
	if t.inst == nil {
		return t.obj
	}
	return t.inst.orig.obj
}

// Origin returns the generic type from which the named type t is
// instantiated. If t is not an instantiated type, the result is t.
func (t *Named) Origin() *Named {
	if t.inst == nil {
		return t
	}
	return t.inst.orig

	Sum        string           `json:",omitempty"` // checksum for path, version (as in go.sum)
	GoModSum   string           `json:",omitempty"` // checksum for go.mod (as in go.sum)
	Origin     *codehost.Origin `json:",omitempty"` // provenance of module
	Reuse      bool             `json:",omitempty"` // reuse of old module info is safe
}

type ModuleError struct {
	Err string // error text
}

	GoMod    string `json:",omitempty"`
	Zip      string `json:",omitempty"`
	Dir      string `json:",omitempty"`
	Sum      string `json:",omitempty"`
	GoModSum string `json:",omitempty"`

	Origin *codehost.Origin `json:",omitempty"`
	Reuse  bool             `json:",omitempty"`
}

func runDownload(ctx context.Context, cmd *base.Command, args []string) {
	modload.InitWorkfile()