Clippy lints / Complexity
Clippy lint · Complexity · checked with Clippy 0.1.99
clippy::needless_update: Checks for needlessly including a base struct on update when all fields are changed anyway. This lint is not applied to structs marked with non_exhaustive
What it meansChecks for needlessly including a base struct on update when all fields are changed anyway. This lint is not applied to structs marked with non_exhaustive. It is in the complexity group and warns by default.
Does it matter?
This will cost resources (because the base has to be somewhere), and make the code less readable.
Code that does something simple in a complicated way. Warns by default.
How to fix it
Clippy does not fix this one automatically. Change the code by hand:
Flagged
Point {
x: 1,
y: 1,
z: 1,
..zero_point
};
Write this instead
Point {
x: 1,
y: 1,
z: 1
};
Turn it off, or on
Allow it where it does not fit your code, as narrowly as you can:
On one item
#[allow(clippy::needless_update)]
fn my_function() { /* ... */ }Whole crate (Cargo.toml)
[lints.clippy]
needless_update = "allow"One run
cargo clippy -- -A clippy::needless-updateThe [lints] table needs Rust 1.74 or newer. In a workspace, put it under [workspace.lints.clippy] and add [lints] workspace = true to each member.
Clippy's own documentation
What it does
Checks for needlessly including a base struct on update when all fields are changed anyway.
This lint is not applied to structs marked with non_exhaustive.
Why is this bad?
This will cost resources (because the base has to be somewhere), and make the code less readable.
Example
Point {
x: 1,
y: 1,
z: 1,
..zero_point
};
Use instead:
Point {
x: 1,
y: 1,
z: 1
};
From the Clippy lint list (0.1.99), part of the Rust project, MIT or Apache-2.0. Official entry.
Related lints
- too_many_argumentsChecks for functions with too many parameters
- clone_on_copyusing `clone` on type `u64` which implements the `Copy` trait
- type_complexityChecks for types used in structs, parameters and let declarations above a certain complexity threshold
- needless_option_takecalled `Option::take()` on a temporary value
- needless_question_markSuggests replacing Ok(x?) or Some(x?) with x in return positions where the ? operator is not needed to convert the type of x
- needless_splitnunnecessary use of `splitn`
- neg_cmp_op_on_partial_ordthe use of negated comparison operators on partially ordered types produces code that is hard to read and refactor, please consider using the `partial_cmp` method instead, to make it clear that the two values could be incomparable
- no_effectstatement with no effect
- nonnull_unchecked_on_box_ptruse of `NonNull::new_unchecked` with `Box::into_raw`
All 847 Clippy lints · Rust compiler errors · Cargo.toml checker
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Related lintclippy::too_many_argumentsChecks for functions with too many parametersRead it next →Did this answer your question?