[8.0]Error `Expected singleton: account.account.type(25, 37)` creating "Accounting Set-Up" about mtd HOT 2 OPEN

Consider whether this is likely to be an issue in:

• 8.0
• 10.0
• 11.0
• 12.0

Fix the issue in:

• 8.0

from mtd.

Effectively, there are at least two taxes that satisfy the following condition in the database in question:

        self.output_account_type = self.env['account.account.type'].search([
            ('code', '=', 'Output Tax'),
            ('name', '=', 'Output Tax')])

but when assigning to a many2one there can only be zero or one records (this makes sense if you think about it).

There's a possibility the line below it might also suffer the same fate, which does similar in the same way but looks for Input Tax.

We need to decide if it's a data bug or it's reasonable to have this situation and therefore should handle it in the code. If it's a data bug, we could at least trap the >2 matches case and throw a more user-friendly error message.

from mtd.