Enum ResolveVersion

pub enum ResolveVersion {
    V1,
    V2,
    V3,
    V4,
    V5,
}

A version to indicate how a Cargo.lock should be serialized.

When creating a new lockfile, the version in ResolveVersion::default is used. If an old version of lockfile already exists, it will stay as-is.

It’s important that if a new version is added that this is not updated until at least the support for the version is in the stable release of Rust.

This resolve version will be used for all new lock files, for example those generated by cargo update (update everything) or building after a cargo new (where no lock file previously existed). This is also used for updated lock files such as when a dependency is added or when a version requirement changes. In this situation Cargo’s updating the lock file anyway so it takes the opportunity to bump the lock file version forward.

It’s theorized that we can add more here over time to track larger changes to the Cargo.lock format, but we’ve yet to see how that strategy pans out.

Variants

V1

Historical baseline for when this abstraction was added.

V2

A more compact format, more amenable to avoiding source-control merge conflicts. The dependencies arrays are compressed and checksums are listed inline.

• Introduced in 2019 in version 1.38.
• New lockfiles use V2 by default from 1.41 to 1.52.

V3

A format that explicitly lists a version at the top of the file as well as changing how git dependencies are encoded. Dependencies with branch = "master" are no longer encoded the same way as those without branch specifiers.

• Introduced in 2020 in version 1.47.
• New lockfiles use V3 by default from in 1.53 to 1.82.

V4

SourceId URL serialization is aware of URL encoding. For example, ?branch=foo bar is now encoded as ?branch=foo+bar and can be decoded back and forth correctly.

• Introduced in 2024 in version 1.78.
• New lockfiles use V4 by default starting in 1.83.

V5

Unstable. Will collect a certain amount of changes and then go.

Changes made:

Implementations

impl ResolveVersion

fn default() -> ResolveVersion

Gets the default lockfile version.

This is intended to be private. You shall use ResolveVersion::with_rust_version always.

Update this and the description of enum variants of ResolveVersion when we’re changing the default lockfile version.

pub fn max_stable() -> ResolveVersion

The maximum version of lockfile made into the stable channel.

Any version larger than this needs -Znext-lockfile-bump to enable.

Update this when you’re going to stabilize a new lockfile format.

pub fn with_rust_version(rust_version: Option<&RustVersion>) -> Self

Gets the default lockfile version for the given Rust version.

Trait Implementations

impl Clone for ResolveVersion

fn clone(&self) -> ResolveVersion

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ResolveVersion

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Ord for ResolveVersion

fn cmp(&self, other: &ResolveVersion) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for ResolveVersion

fn eq(&self, other: &ResolveVersion) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for ResolveVersion

fn partial_cmp(&self, other: &ResolveVersion) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Copy for ResolveVersion

impl Eq for ResolveVersion

impl StructuralPartialEq for ResolveVersion

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 1 byte

Size for each variant:

• V1: 0 bytes
• V2: 0 bytes
• V3: 0 bytes
• V4: 0 bytes
• V5: 0 bytes