It was verified in practice that this test is able to stress much more
the implementation by introducing errors that were only trivially to
detect with different offsets but impossible to detect starting always
at zero and counting bits the full length of the string.

It was verified in practice that this test is able to stress much more
the implementation by introducing errors that were only trivially to
detect with different offsets but impossible to detect starting always
at zero and counting bits the full length of the string.

It was verified that reverting the commit that fixes the bug, the test
no longer passes.

See commit c00453da for more info about the bug.

Fixes issue #1298.

Fixes #621.