Struct EditorSnapshot 

pub struct EditorSnapshot {
    pub version: u32,
    pub mode: SnapshotMode,
    pub cursor: (u32, u32),
    pub lines: Vec<String>,
    pub viewport_top: u32,
    pub registers: Registers,
    pub marks: BTreeMap<char, (u32, u32)>,
}

Coarse editor snapshot suitable for serde round-tripping.

Today’s shape is intentionally minimal — it carries only the bits the runtime crate::Editor knows how to round-trip without the trait extraction (mode, cursor, lines, viewport top, settings). Once Editor<B: Buffer, H: Host> ships under phase 5, this struct grows to cover full SPEC state: registers, marks, jump list, change list, undo tree, full options.

Hosts that persist editor state between sessions should:

• Treat the snapshot as opaque. Don’t manually mutate fields.
• Always check version after deserialization; reject on mismatch rather than attempt migration.

Wire-format stability

• 0.0.x: Self::VERSION bumps with every structural change to the snapshot. Hosts must reject mismatched persisted state — no migration path is offered.
• 0.1.0: Self::VERSION freezes. Hosts persisting editor state between sessions can rely on the wire format being stable for the entire 0.1.x line.
• 0.2.0+: any further structural change to this struct requires a VERSION++ bump and is gated behind a major version bump of the crate.

Fields

version: u32

Format version. See Self::VERSION for the lock policy. Hosts use this to detect mismatched persisted state.

mode: SnapshotMode

Mode at snapshot time (status-line granularity).

cursor: (u32, u32)

Cursor (row, col) in byte indexing.

lines: Vec<String>

Buffer lines. Trailing \n not included.

viewport_top: u32

Viewport top line at snapshot time.

registers: Registers

Register bank. Vim’s "", "0–"9, "a–"z, "+/"*. Skipped for Eq/PartialEq because crate::Registers doesn’t derive them today.

marks: BTreeMap<char, (u32, u32)>

Named marks — both lowercase ('a–'z, buffer-scope) and uppercase ('A–'Z, file-scope). Round-trips across tab swaps in the host.

0.0.36: consolidated from the prior file_marks field; lowercase marks now persist as well since they live in the same unified crate::Editor::marks map.

Implementations

impl EditorSnapshot

pub const VERSION: u32 = 4

Current snapshot format version.

Bumped to 2 in v0.0.8: registers added. Bumped to 3 in v0.0.9: file_marks added. Bumped to 4 in v0.0.36: file_marks → unified marks map (lowercase + uppercase consolidated).

Lock policy

• 0.0.x (today): VERSION bumps freely with each structural change to EditorSnapshot. Persisted state from an older patch release will not round-trip; hosts must reject the snapshot rather than attempt a field-by-field migration.
• 0.1.0: VERSION freezes. Hosts persisting editor state between sessions can rely on the wire format being stable for the entire 0.1.x line.
• 0.2.0+: any further structural change requires VERSION++ together with a major-version bump of hjkl-engine.

Trait Implementations

impl Clone for EditorSnapshot

fn clone(&self) -> EditorSnapshot

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for EditorSnapshot

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for EditorSnapshot

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for EditorSnapshot

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

where __S: Serializer,

Serialize this value into the given Serde serializer.