Implemented option_option lint #2299
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clippy_lints/src/types.rs
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| cx, | ||
| OPTION_OPTION, | ||
| ast_ty.span, | ||
| "consider using `Option<T>` instead of `Option<Option<T>>`", |
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... "or a custom enum if you need to distinguish all 3 cases"
clippy_lints/src/types.rs
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| OPTION_OPTION, | ||
| ast_ty.span, | ||
| "consider using `Option<T>` instead of `Option<Option<T>>`", | ||
| "`Option<_>` is easier to use than `Option<Option<_>`", |
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I don't think this needs the additional help. Just use span_lint
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I made the requested changes. |
| output_nested(); | ||
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| // The lint allows this | ||
| let local: Option<Option<u8>> = None; |
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Do you know why this isn't linted?
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Based on the discussion in #97. I thought the lint shouldn't apply to local bindings.
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I looked through the discussion and could not find anything. Can you quote what you mean?
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#97 (comment)
"It should catch Option<Option<..>> types in function signatures and perhaps typedefs."
I took this to mean only function signatures, struct definitions and enum definitions. I might have been incorrect.
In any case, I think it would be strange to allow the type in expressions but not allow naming those expressions local bindings. Maybe we should move this discussion back into the issue if you want to discuss further.
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Being conservative is fine here.
Rename `vec` to `ty` in `match_type_parameter`. This variable is a type and not a vector. Previously it would only refer to `Vec<_>` so the name used to make sense.
ghost
deleted the
This implements the lint introduced in issue #97