undoredo 0.12.0

Undo/Redo in Rust using deltas, snapshots or commands with convenience implementations for many standard and third-party types.
Documentation 
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// SPDX-FileCopyrightText: 2026 undoredo contributors
//
// SPDX-License-Identifier: MIT OR Apache-2.0

use crate::{ApplyEdit, ExtractEdit, RevertEdit};

/// A snapshot of the whole state of a container.
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
#[derive(Clone, Debug, Default, PartialEq)]
pub struct Snapshot<T> {
    state: T,
}

impl<T> Snapshot<T> {
    /// Create a new snapshot from a state of a target.
    #[inline]
    pub fn new(state: T) -> Self {
        Self { state }
    }

    /// Dissolve the snapshot, returning the state it was holding.
    #[inline]
    pub fn dissolve(self) -> T {
        self.state
    }
}

impl<T: Clone> ApplyEdit<T> for Snapshot<T> {
    #[inline]
    fn apply_edit(self, target: &mut T) {
        *target = self.state;
    }
}

impl<T: Clone> RevertEdit<T> for Snapshot<T> {
    #[inline]
    fn revert_edit(self, target: &mut T) -> Self {
        let reverse = Self::new(target.clone());
        *target = self.state;

        reverse
    }
}

impl<T: Clone> ExtractEdit<T> for Snapshot<T> {
    #[inline]
    fn extract_edit(target: &mut T) -> Self {
        Self::new(target.clone())
    }
}