Struct SymbolicRefs 

pub struct SymbolicRefs(/* private fields */);

Maintains an acyclic set of symbolic references. Note that dangling references are not detected.

Internally, targets are stored as Target, which distinguishes direct (qualified) targets from symbolic (intermediate) ones. This means resolution and cycle-checking can pattern-match on the variant rather than re-parsing the string.

Deserialization Order

Deserialization validates entries in iteration order via TryFrom<IndexMap>. This means deserialization only succeeds if symbolic reference whose target is another symbolic reference appears after that target in the JSON. For example, {"MAIN": "refs/heads/master", "HEAD": "MAIN"} is valid, but {"HEAD": "MAIN", "MAIN": "refs/heads/master"} is not.

To ensure that serialization and deserialization are inverses, we must ensure that insertion order and iteration order are the same. We do this by using IndexMap internally, which preserves this property, and enabling the feature preserve_order of the serde_json crate.

Normally, JSON objects are unordered (see RFC 8259, Sec. 4). Any compatible (de-)serializer must preserve key order.

Implementations

impl SymbolicRefs

Read-only access.

pub fn iter(&self) -> impl Iterator<Item = (&RefString, &Target)>

Returns an iterator over all contained symbolic references, as pairs of their name and Target.

pub fn iter_resolved( &self, ) -> impl Iterator<Item = (&RefString, &Qualified<'static>)>

Returns an iterator over all contained symbolic references that resolve to a direct (qualified) target. The yielded target is the final Qualified reference after chasing through any intermediate symbolic references.

pub fn is_empty(&self) -> bool

Returns true if the set of symbolic references is empty.

impl SymbolicRefs

Utilities for handling of HEAD.

pub fn head(branch_name: &RefString) -> SymbolicRefs

Construct SymbolicRefs for the single symbolic reference HEAD targeting /refs/heads/<branch_name>.

pub fn resolve_head(&self) -> Option<&Qualified<'static>>

Convenience method to get the resolved target of the HEAD reference. Returns the final Qualified reference after chasing the chain. See also SymbolicRefs::head.

impl SymbolicRefs

Mutability.

pub fn combine(&mut self, other: SymbolicRefs) -> Result<(), InsertionError>

Consume other by iteratively inserting into self.

Trait Implementations

impl Clone for SymbolicRefs

fn clone(&self) -> SymbolicRefs

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SymbolicRefs

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

Formats the value using the given formatter.

impl Default for SymbolicRefs

fn default() -> SymbolicRefs

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for SymbolicRefs

fn deserialize<__D>( __deserializer: __D, ) -> Result<SymbolicRefs, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for SymbolicRefs

fn eq(&self, other: &SymbolicRefs) -> 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 SymbolicRefs

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl TryFrom<IndexMap<Unprotected<RefString>, Unprotected<RefString>>> for SymbolicRefs

type Error = InsertionError

The type returned in the event of a conversion error.

fn try_from( map: IndexMap<Unprotected<RefString>, Unprotected<RefString>>, ) -> Result<SymbolicRefs, <SymbolicRefs as TryFrom<IndexMap<Unprotected<RefString>, Unprotected<RefString>>>>::Error>

Performs the conversion.

impl Eq for SymbolicRefs

impl StructuralPartialEq for SymbolicRefs