// Copyright 2023 The Jujutsu Authors//// Licensed under the Apache License, Version 2.0 (the "License");// you may not use this file except in compliance with the License.// You may obtain a copy of the License at//// https://www.apache.org/licenses/LICENSE-2.0//// Unless required by applicable law or agreed to in writing, software// distributed under the License is distributed on an "AS IS" BASIS,// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.// See the License for the specific language governing permissions and// limitations under the License. //! Defines the interface for the working copy. See `LocalWorkingCopy` for the//! default local-disk implementation. use std::any::Any;use std::collections::BTreeMap;use std::ffi::OsString;use std::path::PathBuf;use std::sync::Arc; use async_trait::async_trait;use thiserror::Error;use tracing::instrument; use crate::backend::BackendError;use crate::commit::Commit;use crate::gitignore::GitIgnoreError;use crate::gitignore::GitIgnoreFile;use crate::matchers::Matcher;use crate::merged_tree::MergedTree;use crate::op_store::OpStoreError;use crate::op_store::OperationId;use crate::op_walk;use crate::operation::Operation;use crate::ref_name::WorkspaceName;use crate::ref_name::WorkspaceNameBuf;use crate::repo::ReadonlyRepo;use crate::repo::Repo as _;use crate::repo::RewriteRootCommit;use crate::repo_path::InvalidRepoPathError;use crate::repo_path::RepoPath;use crate::repo_path::RepoPathBuf;use crate::settings::UserSettings;use crate::store::Store;use crate::transaction::TransactionCommitError; /// The trait all working-copy implementations must implement.#[async_trait(?Send)]pub trait WorkingCopy: Any + Send {    /// The name/id of the implementation. Used for choosing the right    /// implementation when loading a working copy.    fn name(&self) -> &str;     /// The working copy's workspace name (or identifier.)    fn workspace_name(&self) -> &WorkspaceName;     /// The operation this working copy was most recently updated to.    fn operation_id(&self) -> &OperationId;     /// The tree this working copy was most recently updated to.    fn tree(&self) -> Result<&MergedTree, WorkingCopyStateError>;     /// Patterns that decide which paths from the current tree should be checked    /// out in the working copy. An empty list means that no paths should be    /// checked out in the working copy. A single `RepoPath::root()` entry means    /// that all files should be checked out.    fn sparse_patterns(&self) -> Result<&[RepoPathBuf], WorkingCopyStateError>;     /// Locks the working copy and returns an instance with methods for updating    /// the working copy files and state.    async fn start_mutation(&self) -> Result<Box<dyn LockedWorkingCopy>, WorkingCopyStateError>;} impl dyn WorkingCopy {    /// Returns reference of the implementation type.    pub fn downcast_ref<T: WorkingCopy>(&self) -> Option<&T> {        (self as &dyn Any).downcast_ref()    }} /// The factory which creates and loads a specific type of working copy.pub trait WorkingCopyFactory {    /// Create a new working copy from scratch.    fn init_working_copy(        &self,        store: Arc<Store>,        working_copy_path: PathBuf,        state_path: PathBuf,        operation_id: OperationId,        workspace_name: WorkspaceNameBuf,        settings: &UserSettings,    ) -> Result<Box<dyn WorkingCopy>, WorkingCopyStateError>;     /// Load an existing working copy.    fn load_working_copy(        &self,        store: Arc<Store>,        working_copy_path: PathBuf,        state_path: PathBuf,        settings: &UserSettings,    ) -> Result<Box<dyn WorkingCopy>, WorkingCopyStateError>;} /// A working copy that's being modified.#[async_trait]pub trait LockedWorkingCopy: Any + Send {    /// The operation at the time the lock was taken    fn old_operation_id(&self) -> &OperationId;     /// The tree at the time the lock was taken    fn old_tree(&self) -> &MergedTree;     /// Snapshot the working copy. Returns the tree and stats.    async fn snapshot(        &mut self,        options: &SnapshotOptions,    ) -> Result<(MergedTree, SnapshotStats), SnapshotError>;     /// Check out the specified commit in the working copy.    async fn check_out(&mut self, commit: &Commit) -> Result<CheckoutStats, CheckoutError>;     /// Update the workspace name.    fn rename_workspace(&mut self, new_workspace_name: WorkspaceNameBuf);     /// Update to another commit without touching the files in the working copy.    async fn reset(&mut self, commit: &Commit) -> Result<(), ResetError>;     /// Update to another commit without touching the files in the working copy,    /// without assuming that the previous tree exists.    async fn recover(&mut self, commit: &Commit) -> Result<(), ResetError>;     /// See `WorkingCopy::sparse_patterns()`    fn sparse_patterns(&self) -> Result<&[RepoPathBuf], WorkingCopyStateError>;     /// Updates the patterns that decide which paths from the current tree    /// should be checked out in the working copy.    // TODO: Use a different error type here so we can include a    // `SparseNotSupported` variants for working copies that don't support sparse    // checkouts (e.g. because they use a virtual file system so there's no reason    // to use sparse).    async fn set_sparse_patterns(        &mut self,        new_sparse_patterns: Vec<RepoPathBuf>,    ) -> Result<CheckoutStats, CheckoutError>;     /// Finish the modifications to the working copy by writing the updated    /// states to disk. Returns the new (unlocked) working copy.    async fn finish(        self: Box<Self>,        operation_id: OperationId,    ) -> Result<Box<dyn WorkingCopy>, WorkingCopyStateError>;} impl dyn LockedWorkingCopy {    /// Returns reference of the implementation type.    pub fn downcast_ref<T: LockedWorkingCopy>(&self) -> Option<&T> {        (self as &dyn Any).downcast_ref()    }     /// Returns mutable reference of the implementation type.    pub fn downcast_mut<T: LockedWorkingCopy>(&mut self) -> Option<&mut T> {        (self as &mut dyn Any).downcast_mut()    }} /// An error while snapshotting the working copy.#[derive(Debug, Error)]pub enum SnapshotError {    /// A tracked path contained invalid component such as `..`.    #[error(transparent)]    InvalidRepoPath(#[from] InvalidRepoPathError),    /// A path in the working copy was not valid UTF-8.    #[error("Working copy path {} is not valid UTF-8", path.to_string_lossy())]    InvalidUtf8Path {        /// The path with invalid UTF-8.        path: OsString,    },    /// A symlink target in the working copy was not valid UTF-8.    #[error("Symlink {path} target is not valid UTF-8")]    InvalidUtf8SymlinkTarget {        /// The path of the symlink that has a target that's not valid UTF-8.        /// This path itself is valid UTF-8.        path: PathBuf,    },    /// Reading or writing from the commit backend failed.    #[error(transparent)]    BackendError(#[from] BackendError),    /// Checking path with ignore patterns failed.    #[error(transparent)]    GitIgnoreError(#[from] GitIgnoreError),    /// Failed to load the working copy state.    #[error(transparent)]    WorkingCopyStateError(#[from] WorkingCopyStateError),    /// Some other error happened while snapshotting the working copy.    #[error("{message}")]    Other {        /// Error message.        message: String,        /// The underlying error.        #[source]        err: Box<dyn std::error::Error + Send + Sync>,    },} /// Options used when snapshotting the working copy. Some of them may be ignored/// by some `WorkingCopy` implementations.#[derive(Clone)]pub struct SnapshotOptions<'a> {    /// The `.gitignore`s to use while snapshotting. The typically come from the    /// user's configured patterns combined with per-repo patterns.    // The base_ignores are passed in here rather than being set on the TreeState    // because the TreeState may be long-lived if the library is used in a    // long-lived process.    pub base_ignores: Arc<GitIgnoreFile>,    /// A callback for the UI to display progress.    pub progress: Option<&'a SnapshotProgress<'a>>,    /// For new files that are not already tracked, start tracking them if they    /// match this.    pub start_tracking_matcher: &'a dyn Matcher,    /// For files that match the ignore patterns or are too large, start    /// tracking them anyway if they match this.    pub force_tracking_matcher: &'a dyn Matcher,    /// The size of the largest file that should be allowed to become tracked    /// (already tracked files are always snapshotted). If there are larger    /// files in the working copy, then `LockedWorkingCopy::snapshot()` may    /// (depending on implementation)    /// return `SnapshotError::NewFileTooLarge`.    pub max_new_file_size: u64,} /// A callback for getting progress updates.pub type SnapshotProgress<'a> = dyn Fn(&RepoPath) + 'a + Sync; /// Stats about a snapshot operation on a working copy.#[derive(Clone, Debug, Default)]pub struct SnapshotStats {    /// List of new (previously untracked) files which are still untracked.    pub untracked_paths: BTreeMap<RepoPathBuf, UntrackedReason>,} /// Reason why the new path isn't tracked.#[derive(Clone, Debug)]pub enum UntrackedReason {    /// File was larger than the specified maximum file size.    FileTooLarge {        /// Actual size of the large file.        size: u64,        /// Maximum allowed size.        max_size: u64,    },    /// File does not match the fileset specified in snapshot.auto-track.    FileNotAutoTracked,} /// Stats about a checkout operation on a working copy. All "files" mentioned/// below may also be symlinks or materialized conflicts.#[derive(Debug, PartialEq, Eq, Clone, Default)]pub struct CheckoutStats {    /// The number of files that were updated in the working copy.    /// These files existed before and after the checkout.    pub updated_files: u32,    /// The number of files added in the working copy.    pub added_files: u32,    /// The number of files removed in the working copy.    pub removed_files: u32,    /// The number of files that were supposed to be updated or added in the    /// working copy but were skipped because there was an untracked (probably    /// ignored) file in its place.    pub skipped_files: u32,} /// The working-copy checkout failed.#[derive(Debug, Error)]pub enum CheckoutError {    /// The current working-copy commit was deleted, maybe by an overly    /// aggressive GC that happened while the current process was running.    #[error("Current working-copy commit not found")]    SourceNotFound {        /// The underlying error.        source: Box<dyn std::error::Error + Send + Sync>,    },    /// Another process checked out a commit while the current process was    /// running (after the working copy was read by the current process).    #[error("Concurrent checkout")]    ConcurrentCheckout,    /// Path in the commit contained invalid component such as `..`.    #[error(transparent)]    InvalidRepoPath(#[from] InvalidRepoPathError),    /// Path contained reserved name which cannot be checked out to disk.    #[error("Reserved path component {name} in {path}")]    ReservedPathComponent {        /// The file or directory path.        path: PathBuf,        /// The reserved path component.        name: &'static str,    },    /// Reading or writing from the commit backend failed.    #[error("Internal backend error")]    InternalBackendError(#[from] BackendError),    /// Failed to load the working copy state.    #[error(transparent)]    WorkingCopyStateError(#[from] WorkingCopyStateError),    /// Some other error happened while checking out the working copy.    #[error("{message}")]    Other {        /// Error message.        message: String,        /// The underlying error.        #[source]        err: Box<dyn std::error::Error + Send + Sync>,    },} /// An error while resetting the working copy.#[derive(Debug, Error)]pub enum ResetError {    /// The current working-copy commit was deleted, maybe by an overly    /// aggressive GC that happened while the current process was running.    #[error("Current working-copy commit not found")]    SourceNotFound {        /// The underlying error.        source: Box<dyn std::error::Error + Send + Sync>,    },    /// Reading or writing from the commit backend failed.    #[error("Internal error")]    InternalBackendError(#[from] BackendError),    /// Failed to load the working copy state.    #[error(transparent)]    WorkingCopyStateError(#[from] WorkingCopyStateError),    /// Some other error happened while resetting the working copy.    #[error("{message}")]    Other {        /// Error message.        message: String,        /// The underlying error.        #[source]        err: Box<dyn std::error::Error + Send + Sync>,    },} /// Whether the working copy is stale or not.#[derive(Clone, Debug, Eq, PartialEq)]pub enum WorkingCopyFreshness {    /// The working copy isn't stale, and no need to reload the repo.    Fresh,    /// The working copy was updated since we loaded the repo. The repo must be    /// reloaded at the working copy's operation.    Updated(Box<Operation>),    /// The working copy is behind the latest operation.    WorkingCopyStale,    /// The working copy is a sibling of the latest operation.    SiblingOperation,} impl WorkingCopyFreshness {    /// Determine the freshness of the provided working copy relative to the    /// target commit.    #[instrument(skip_all)]    pub async fn check_stale(        locked_wc: &dyn LockedWorkingCopy,        wc_commit: &Commit,        repo: &ReadonlyRepo,    ) -> Result<Self, OpStoreError> {        // Check if the working copy's operation matches the repo's operation        if locked_wc.old_operation_id() == repo.op_id() {            // The working copy isn't stale, and no need to reload the repo.            Ok(Self::Fresh)        } else {            let wc_operation = repo                .loader()                .load_operation(locked_wc.old_operation_id())                .await?;            let repo_operation = repo.operation();            let ancestor_ops =                op_walk::closest_common_ancestors([wc_operation.clone()], [repo_operation.clone()])                    .await?;            // TODO: test all operations instead of using only a single common operation            let ancestor_op = ancestor_ops.into_iter().next().unwrap();            if ancestor_op.id() == repo_operation.id() {                // The working copy was updated since we loaded the repo. The repo must be                // reloaded at the working copy's operation.                Ok(Self::Updated(Box::new(wc_operation)))            } else if ancestor_op.id() == wc_operation.id() {                // The working copy was not updated when some repo operation committed,                // meaning that it's stale compared to the repo view.                if locked_wc.old_tree().tree_ids_and_labels()                    == wc_commit.tree().tree_ids_and_labels()                {                    // The working copy doesn't require any changes                    Ok(Self::Fresh)                } else {                    Ok(Self::WorkingCopyStale)                }            } else {                Ok(Self::SiblingOperation)            }        }    }} /// An error while recovering a stale working copy.#[derive(Debug, Error)]pub enum RecoverWorkspaceError {    /// Backend error.    #[error(transparent)]    Backend(#[from] BackendError),    /// Error during checkout.    #[error(transparent)]    Reset(#[from] ResetError),    /// Checkout attempted to modify the root commit.    #[error(transparent)]    RewriteRootCommit(#[from] RewriteRootCommit),    /// Error during transaction.    #[error(transparent)]    TransactionCommit(#[from] TransactionCommitError),    /// Working copy commit is missing.    #[error(r#""{}" doesn't have a working-copy commit"#, .0.as_symbol())]    WorkspaceMissingWorkingCopy(WorkspaceNameBuf),} /// Recover this workspace to its last known checkout.pub async fn create_and_check_out_recovery_commit(    locked_wc: &mut dyn LockedWorkingCopy,    repo: &Arc<ReadonlyRepo>,    workspace_name: WorkspaceNameBuf,    description: &str,) -> Result<(Arc<ReadonlyRepo>, Commit), RecoverWorkspaceError> {    let mut tx = repo.start_transaction();    let repo_mut = tx.repo_mut();     let commit_id = repo        .view()        .get_wc_commit_id(&workspace_name)        .ok_or_else(|| {            RecoverWorkspaceError::WorkspaceMissingWorkingCopy(workspace_name.clone())        })?;    let commit = repo.store().get_commit_async(commit_id).await?;    let new_commit = repo_mut        .new_commit(vec![commit_id.clone()], commit.tree())        .set_description(description)        .write()        .await?;    repo_mut.set_wc_commit(workspace_name, new_commit.id().clone())?;     let repo = tx.commit("recovery commit").await?;    locked_wc.recover(&new_commit).await?;     Ok((repo, new_commit))} /// An error while reading the working copy state.#[derive(Debug, Error)]#[error("{message}")]pub struct WorkingCopyStateError {    /// Error message.    pub message: String,    /// The underlying error.    #[source]    pub err: Box<dyn std::error::Error + Send + Sync>,}