Incomplete symbol is not fixed up by importing a package

[firelizzard18]

The following program sample.go triggers an unexpected result

func TestIssueX(t *testing.T) {
	i := interp.New(interp.Options{Env: []string{"foo=bar"}})
	err := i.Use(stdlib.Symbols)
	if err != nil {
		t.Fatal(err)
	}

	_, err = i.Eval(`x := errors.New("")`)
	if err == nil {
		t.Fatal("Expected an error")
	}

	_, err = i.Eval(`import "errors"`)
	if err != nil {
		t.Fatal(err)
	}

	_, err = i.Eval(`x := errors.New("")`)
	if err != nil {
		t.Fatal(err)
	}
}

Expected result

$ go test
=== RUN   TestIssueX
Hello
--- PASS: TestIssueX (0.00s)
PASS
ok      github.com/traefik/yaegi/interp 0.007s

Got

$ go test
=== RUN   TestIssueX
    /home/firelizzard/src/yaegi-fork/interp/interp_eval_test.go:1767: <nil>
--- FAIL: TestIssueX (0.00s)
FAIL
FAIL	github.com/traefik/yaegi/interp	0.007s

Yaegi Version

5665c9a

Additional Notes

No response