Enum IndexStrategy 

pub enum IndexStrategy {
    FirstIndex,
    UnsafeFirstMatch,
    UnsafeBestMatch,
}

Variants

FirstIndex

Only use results from the first index that returns a match for a given package name.

While this differs from pip’s behavior, it’s the default index strategy as it’s the most secure.

UnsafeFirstMatch

Search for every package name across all indexes, exhausting the versions from the first index before moving on to the next.

In this strategy, we look for every package across all indexes. When resolving, we attempt to use versions from the indexes in order, such that we exhaust all available versions from the first index before moving on to the next. Further, if a version is found to be incompatible in the first index, we do not reconsider that version in subsequent indexes, even if the secondary index might contain compatible versions (e.g., variants of the same versions with different ABI tags or Python version constraints).

See: https://peps.python.org/pep-0708/

UnsafeBestMatch

Search for every package name across all indexes, preferring the “best” version found. If a package version is in multiple indexes, only look at the entry for the first index.

In this strategy, we look for every package across all indexes. When resolving, we consider all versions from all indexes, choosing the “best” version found (typically, the highest compatible version).

This most closely matches pip’s behavior, but exposes the resolver to “dependency confusion” attacks whereby malicious actors can publish packages to public indexes with the same name as internal packages, causing the resolver to install the malicious package in lieu of the intended internal package.

See: https://peps.python.org/pep-0708/

Trait Implementations

impl Clone for IndexStrategy

fn clone(&self) -> IndexStrategy

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for IndexStrategy

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

Formats the value using the given formatter.

impl Default for IndexStrategy

fn default() -> IndexStrategy

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for IndexStrategy

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for IndexStrategy

fn eq(&self, other: &IndexStrategy) -> 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 Serialize for IndexStrategy

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Copy for IndexStrategy

impl Eq for IndexStrategy

impl StructuralPartialEq for IndexStrategy