Impacted versions:
10.0 + e

Steps to reproduce:
1) Create a salary rule that has 'appears_on_payslip' = False.
- An example would be a company contribution that the employee does not need to see.
  2) Add it to a salary structure
  3) run a payroll/payslip calculation

Current behavior:
Numerous thing.
1) Every time you compute sheet, you will duplicate these 'hidden' lines
2) details_by_salary_rule_category no longer has any of the hidden lines, though they certainly contribute to categories (e.g. tests will fail, and bad things)
3) when using hr_payroll_account, lines with contribution registers and accounts that SHOULD be on the journal entry are not !!

Expected behavior:
1) every time you compute the sheet, the lines should be deleted and recalculated
2) details_by_salary_rule_category should have all categories (to be able to make complex rules and tests)
3) journal entry should have a line for every line with an account

Pull Request eminent.

return self.write({'state': 'draft'})
    @api.multi
    def close_payslip_run(self):
        return self.write({'state': 'close'})
class HrPayslip(models.Model):
    _name = 'hr.payslip'
    _description = 'Pay Slip'
    struct_id = fields.Many2one('hr.payroll.structure', string='Structure',
        readonly=True, states={'draft': [('readonly', False)]},
        help='Defines the rules that have to be applied to this payslip, accordingly '
             'to the contract chosen. If you let empty the field contract, this field isn\'t '
             'mandatory anymore and thus the rules applied will be all the rules set on the '
             'structure of all contracts of the employee valid for the chosen period')
    name = fields.Char(string='Payslip Name', readonly=True,
        states={'draft': [('readonly', False)]})