Use type assertion[1] to convert err to the concrete LibnbdError so we can verify the expected Errno. The assertion will panic if err is not a LibnbdError. [1] https://tour.golang.org/methods/15 Signed-off-by: Nir Soffer <nsoffer@redhat.com> --- golang/src/libguestfs.org/libnbd/libnbd_610_error_test.go | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/golang/src/libguestfs.org/libnbd/libnbd_610_error_test.go b/golang/src/libguestfs.org/libnbd/libnbd_610_error_test.go index 27540ce..0f81e76 100644 --- a/golang/src/libguestfs.org/libnbd/libnbd_610_error_test.go +++ b/golang/src/libguestfs.org/libnbd/libnbd_610_error_test.go @@ -18,7 +18,7 @@ package libnbd -import "fmt" +import "syscall" import "testing" func Test610Error(t *testing.T) { @@ -34,8 +34,7 @@ func Test610Error(t *testing.T) { err = h.Pread(buf, 0, nil) if err == nil { t.Fatalf("expected an error from operation") + } else if err.(*LibnbdError).Errno != syscall.ENOTCONN { + t.Fatalf("unexpected error: %s", err) } - fmt.Printf("error = %s\n", err) - /* XXX We expect the errno to be ENOTCONN, but I couldn't work - out how to test it. */ } -- 2.31.1