derive_opportunity

derive_opportunity

What it does

Checks for data structures that could derive additional traits.

Why is this bad?

Not deriving the additional traits could be a missed opportunity.

Known problems

• This lint is noisy! The at_least_one_field and ignore options (see below) can be used to make the lint less noisy.
• Currently does not support traits with type or constant parameters (e.g., PartialEq), or traits with supertraits with type or constant parameters (e.g., Eq).

Example

#[derive(Default)]
struct S;

struct T(S);

Use instead:

#[derive(Default)]
struct S;

#[derive(Default)]
struct T(S);

Configuration

• at_least_one_field: bool (default false): If set to true, the lint suggests to derive a trait only when there is at least one field that implements (or could derive) the trait.
• ignore: Vec<String> (default []): A list of macro paths the lint should not suggest to derive.