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.

from odoo import api, models
class PayslipDetailsReport(models.AbstractModel):
    _name = 'report.hr_payroll.report_payslipdetails'
    def get_details_by_rule_category(self, payslip_lines):
        PayslipLine = self.env['hr.payslip.line']
        RuleCateg = self.env['hr.salary.rule.category']
        def get_recursive_parent(current_rule_category, rule_categories=None):
            if rule_categories:
                rule_categories = current_rule_category | rule_categories
            else:
                rule_categories = current_rule_category
            if current_rule_category.parent_id:
                return get_recursive_parent(current_rule_category.parent_id, rule_categories)
            else:
                return rule_categories
        res = {}
        result = {}
        if payslip_lines:
            self.env.cr.execute("""
                SELECT pl.id, pl.category_id, pl.slip_id FROM hr_payslip_line as pl
                LEFT JOIN hr_salary_rule_category AS rc on (pl.category_id = rc.id)
                WHERE pl.id in %s
                GROUP BY rc.parent_id, pl.sequence, pl.id, pl.category_id
                ORDER BY pl.sequence, rc.parent_id""",