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Name::from<&str> always heap-allocates which is a footgun #24465

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#24544
Open
Name::from<&str> always heap-allocates which is a footgun#24465
#24544
Labels
A-UtilsUtility functions and typesC-BugAn unexpected or incorrect behaviorC-PerformanceA change motivated by improving speed, memory usage or compile timesD-StraightforwardSimple bug fixes and API improvements, docs, test and examplesS-Ready-For-ImplementationThis issue is ready for an implementation PR. Go for it!
@beicause

Description

@beicause
beicause
opened on May 28, 2026

Bevy version and features

main

What went wrong

Name internally is Cow<'static, str>, but creating Name by "str".into is always heap-allocated even if &str has static lifetime:

bevy/crates/bevy_ecs/src/name.rs

Lines 173 to 175 in 564eb4f

fn from(name: &str) -> Self {
Name::new(name.to_owned())
}

The correct way is Name::new("str")

bevy/crates/bevy_ecs/src/name.rs

Lines 79 to 81 in 564eb4f

pub fn new(name: impl Into<Cow<'static, str>>) -> Self {
Self(HashedStr(Hashed::new(name.into())))
}

To avoid the unexpected allocation I suggest change impl From<&str> for Name to impl From<&'static str> for Name

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    A-UtilsUtility functions and typesC-BugAn unexpected or incorrect behaviorC-PerformanceA change motivated by improving speed, memory usage or compile timesD-StraightforwardSimple bug fixes and API improvements, docs, test and examplesS-Ready-For-ImplementationThis issue is ready for an implementation PR. Go for it!

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