Method `get_default_fields`
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Currently all the methods beginning by `get_default` are used to fetch their default values, usually by looking in the ir.config_parameter table.
As several methods `get_default_fields` have been defined in res_config classes, it better to define it in base and calling to super to avoid side effects like the following example
- 2 classes that override the same class and define the same method. In that case one method will never be called, as it is ovewritten by the other.
Method `set_fields`
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Currently all the methods beginning by `set_` are used to set their values, usually in the ir.config_parameter table.
As several methods `set_fields` have been defined in res_config classes, it better to define it in base and calling to super to avoid side effects like the following example
- 2 classes that override the same class and define the same method. In that case one method will never be called, as it is ovewritten by the other.
Methods `get_default_foo` and `set_foo`
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This commit deprecates the method starting with `get_default_` or `set_` in the res.config models. A warning is raised in that case.