Question about test file

[alien315]

Just curious but in your test file you have:

// should approve max of msg.sender & withdraw 20 without changing allowance (should succeed).
it('approvals: msg.sender approves accounts[1] of max (2^256 - 1) & withdraws 20', async () => {

Why this test should succeed? is not a bug that a token holder can withdraw without changing the allowance?