Struct HistoryGroup 

pub struct HistoryGroup {

    pub key: String,
    pub name: Option<String>,
    pub record_id: Option<String>,
    pub named_by: Option<HistoryAuthor>,
    pub open: bool,
    pub start: usize,
    pub end: usize,
    pub children: Vec<HistoryGroup>,
    pub depth: usize,
    pub authors: Vec<HistoryAuthor>,
    pub families: Vec<OpFamily>,
    pub first_time: SystemTime,
    pub last_time: SystemTime,
    pub text_delta: Option<(usize, usize)>,
    pub first_entry: HistoryEntryId,
    pub last_entry: HistoryEntryId,
}

One collapsible band in a history surface.

start..end are indices into the entry slice the group was built from, in the producer’s causal order. children are named sub-ranges; entries inside start..end that no child covers are the group’s own rows.

Fields

key: String

Derived from the group’s first change, which does not move as the group grows, so expand/collapse survives a refresh.

name: Option<String>

record_id: Option<String>

Record id of the naming, so a rename can address it.

named_by: Option<HistoryAuthor>

open: bool

True while the range is still absorbing new changes.

start: usize

end: usize

children: Vec<HistoryGroup>

At most MAX_GROUP_DEPTH deep in total.

depth: usize

0 for a top-level group.

authors: Vec<HistoryAuthor>

First-seen order.

families: Vec<OpFamily>

First-seen order.

first_time: SystemTime

Both are UNIX_EPOCH when no change in the range carried a clock.

last_time: SystemTime

text_delta: Option<(usize, usize)>

None when at least one change in the range didn’t report a count — a partial total would read as a complete one.

first_entry: HistoryEntryId

The last one is the restore target: “restore to the end of this version”.

last_entry: HistoryEntryId

Implementations

impl HistoryGroup

pub fn len(&self) -> usize

Number of changes in the range, including those inside children.

pub fn is_empty(&self) -> bool

pub fn is_bare_change(&self) -> bool

True when this band is a single unnamed change — the surfaces render those as a plain row rather than as a group with one thing in it.

pub fn title(&self, entries: &[HistoryEntry]) -> String

The line a reader scans: the user’s name, or a derived description of what the range contains.

The derived form never claims more than it counted. It says how many changes and, when the range spans a minute or more, over how long.

pub fn subtitle(&self, entries: &[HistoryEntry]) -> String

The dim second line: who, and how much moved.

pub fn authors_label(&self) -> String

“Alice”, “Alice and Bob”, “Alice, Bob + 4”.

pub fn span_label(&self) -> Option<String>

How long the range took, in the coarsest unit that is still true, or None when it is under a minute or no change carried a clock.

pub fn direct_spans(&self) -> Vec<Range<usize>>

Index ranges of this group’s own rows — everything in start..end that no child covers. In ascending order.

pub fn walk<'a>(&'a self, out: &mut Vec<&'a HistoryGroup>)

Every group in this subtree, self first, then children. Used by the surfaces to flatten a forest into a row list.

Trait Implementations

impl Clone for HistoryGroup

fn clone(&self) -> HistoryGroup

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for HistoryGroup

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

Formats the value using the given formatter.

impl PartialEq for HistoryGroup

fn eq(&self, other: &HistoryGroup) -> 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 StructuralPartialEq for HistoryGroup