// Copyright 2024 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. //! Code for working with copies and renames. use std::collections::HashMap;use std::pin::Pin;use std::task::Context;use std::task::Poll;use std::task::ready; use futures::Stream; use crate::backend::BackendResult;use crate::backend::CopyRecord;use crate::merge::Diff;use crate::merge::MergedTreeValue;use crate::merged_tree::MergedTree;use crate::merged_tree::TreeDiffStream;use crate::repo_path::RepoPath;use crate::repo_path::RepoPathBuf; /// A collection of CopyRecords.#[derive(Default, Debug)]pub struct CopyRecords { records: Vec<CopyRecord>, // Maps from `source` or `target` to the index of the entry in `records`. // Conflicts are excluded by keeping an out of range value. sources: HashMap<RepoPathBuf, usize>, targets: HashMap<RepoPathBuf, usize>,} impl CopyRecords { /// Adds information about `CopyRecord`s to `self`. A target with multiple /// conflicts is discarded and treated as not having an origin. pub fn add_records( &mut self, copy_records: impl IntoIterator<Item = BackendResult<CopyRecord>>, ) -> BackendResult<()> { for record in copy_records { let r = record?; self.sources .entry(r.source.clone()) // TODO: handle conflicts instead of ignoring both sides. .and_modify(|value| *value = usize::MAX) .or_insert(self.records.len()); self.targets .entry(r.target.clone()) // TODO: handle conflicts instead of ignoring both sides. .and_modify(|value| *value = usize::MAX) .or_insert(self.records.len()); self.records.push(r); } Ok(()) } /// Returns true if there are copy records associated with a source path. pub fn has_source(&self, source: &RepoPath) -> bool { self.sources.contains_key(source) } /// Gets any copy record associated with a source path. pub fn for_source(&self, source: &RepoPath) -> Option<&CopyRecord> { self.sources.get(source).and_then(|&i| self.records.get(i)) } /// Returns true if there are copy records associated with a target path. pub fn has_target(&self, target: &RepoPath) -> bool { self.targets.contains_key(target) } /// Gets any copy record associated with a target path. pub fn for_target(&self, target: &RepoPath) -> Option<&CopyRecord> { self.targets.get(target).and_then(|&i| self.records.get(i)) } /// Gets all copy records. pub fn iter(&self) -> impl Iterator<Item = &CopyRecord> { self.records.iter() }} /// Whether or not the source path was deleted.#[derive(Clone, Copy, Debug, Eq, PartialEq)]pub enum CopyOperation { /// The source path was not deleted. Copy, /// The source path was renamed to the destination. Rename,} /// A `TreeDiffEntry` with copy information.pub struct CopiesTreeDiffEntry { /// The path. pub path: CopiesTreeDiffEntryPath, /// The resolved tree values if available. pub values: BackendResult<Diff<MergedTreeValue>>,} /// Path and copy information of `CopiesTreeDiffEntry`.#[derive(Clone, Debug, Eq, PartialEq)]pub struct CopiesTreeDiffEntryPath { /// The source path and copy information if this is a copy or rename. pub source: Option<(RepoPathBuf, CopyOperation)>, /// The target path. pub target: RepoPathBuf,} impl CopiesTreeDiffEntryPath { /// The source path. pub fn source(&self) -> &RepoPath { self.source.as_ref().map_or(&self.target, |(path, _)| path) } /// The target path. pub fn target(&self) -> &RepoPath { &self.target } /// Whether this entry was copied or renamed from the source. Returns `None` /// if the path is unchanged. pub fn copy_operation(&self) -> Option<CopyOperation> { self.source.as_ref().map(|(_, op)| *op) }} /// Wraps a `TreeDiffStream`, adding support for copies and renames.pub struct CopiesTreeDiffStream<'a> { inner: TreeDiffStream<'a>, source_tree: MergedTree, target_tree: MergedTree, copy_records: &'a CopyRecords,} impl<'a> CopiesTreeDiffStream<'a> { /// Create a new diff stream with copy information. pub fn new( inner: TreeDiffStream<'a>, source_tree: MergedTree, target_tree: MergedTree, copy_records: &'a CopyRecords, ) -> Self { Self { inner, source_tree, target_tree, copy_records, } } fn resolve_copy_source( &self, source: &RepoPath, values: BackendResult<Diff<MergedTreeValue>>, ) -> BackendResult<(CopyOperation, Diff<MergedTreeValue>)> { let target_value = values?.after; let source_value = self.source_tree.path_value(source)?; // If the source path is deleted in the target tree, it's a rename. let source_value_at_target = self.target_tree.path_value(source)?; let copy_op = if source_value_at_target.is_absent() || source_value_at_target.is_tree() { CopyOperation::Rename } else { CopyOperation::Copy }; Ok((copy_op, Diff::new(source_value, target_value))) }} impl Stream for CopiesTreeDiffStream<'_> { type Item = CopiesTreeDiffEntry; fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> { while let Some(diff_entry) = ready!(self.inner.as_mut().poll_next(cx)) { let Some(CopyRecord { source, .. }) = self.copy_records.for_target(&diff_entry.path) else { let target_deleted = matches!(&diff_entry.values, Ok(diff) if diff.after.is_absent()); if target_deleted && self.copy_records.has_source(&diff_entry.path) { // Skip the "delete" entry when there is a rename. continue; } return Poll::Ready(Some(CopiesTreeDiffEntry { path: CopiesTreeDiffEntryPath { source: None, target: diff_entry.path, }, values: diff_entry.values, })); }; let (copy_op, values) = match self.resolve_copy_source(source, diff_entry.values) { Ok((copy_op, values)) => (copy_op, Ok(values)), // Fall back to "copy" (= path still exists) if unknown. Err(err) => (CopyOperation::Copy, Err(err)), }; return Poll::Ready(Some(CopiesTreeDiffEntry { path: CopiesTreeDiffEntryPath { source: Some((source.clone(), copy_op)), target: diff_entry.path, }, values, })); } Poll::Ready(None) }}
// Copyright 2024 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.
//! Code for working with copies and renames.
use std::collections::HashMap;
use std::pin::Pin;
use std::task::Context;
use std::task::Poll;
use std::task::ready;
use futures::Stream;
use crate::backend::BackendResult;
use crate::backend::CopyRecord;
use crate::merge::Diff;
use crate::merge::MergedTreeValue;
use crate::merged_tree::MergedTree;
use crate::merged_tree::TreeDiffStream;
use crate::repo_path::RepoPath;
use crate::repo_path::RepoPathBuf;
/// A collection of CopyRecords.
#[derive(Default, Debug)]
pub struct CopyRecords {
records: Vec<CopyRecord>,
// Maps from `source` or `target` to the index of the entry in `records`.
// Conflicts are excluded by keeping an out of range value.
sources: HashMap<RepoPathBuf, usize>,
targets: HashMap<RepoPathBuf, usize>,
}
impl CopyRecords {
/// Adds information about `CopyRecord`s to `self`. A target with multiple
/// conflicts is discarded and treated as not having an origin.
pub fn add_records(
&mut self,
copy_records: impl IntoIterator<Item = BackendResult<CopyRecord>>,
) -> BackendResult<()> {
for record in copy_records {
let r = record?;
self.sources
.entry(r.source.clone())
// TODO: handle conflicts instead of ignoring both sides.
.and_modify(|value| *value = usize::MAX)
.or_insert(self.records.len());
self.targets
.entry(r.target.clone())
// TODO: handle conflicts instead of ignoring both sides.
.and_modify(|value| *value = usize::MAX)
.or_insert(self.records.len());
self.records.push(r);
}
Ok(())
}
/// Returns true if there are copy records associated with a source path.
pub fn has_source(&self, source: &RepoPath) -> bool {
self.sources.contains_key(source)
}
/// Gets any copy record associated with a source path.
pub fn for_source(&self, source: &RepoPath) -> Option<&CopyRecord> {
self.sources.get(source).and_then(|&i| self.records.get(i))
}
/// Returns true if there are copy records associated with a target path.
pub fn has_target(&self, target: &RepoPath) -> bool {
self.targets.contains_key(target)
}
/// Gets any copy record associated with a target path.
pub fn for_target(&self, target: &RepoPath) -> Option<&CopyRecord> {
self.targets.get(target).and_then(|&i| self.records.get(i))
}
/// Gets all copy records.
pub fn iter(&self) -> impl Iterator<Item = &CopyRecord> {
self.records.iter()
}
}
/// Whether or not the source path was deleted.
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum CopyOperation {
/// The source path was not deleted.
Copy,
/// The source path was renamed to the destination.
Rename,
}
/// A `TreeDiffEntry` with copy information.
pub struct CopiesTreeDiffEntry {
/// The path.
pub path: CopiesTreeDiffEntryPath,
/// The resolved tree values if available.
pub values: BackendResult<Diff<MergedTreeValue>>,
}
/// Path and copy information of `CopiesTreeDiffEntry`.
#[derive(Clone, Debug, Eq, PartialEq)]
pub struct CopiesTreeDiffEntryPath {
/// The source path and copy information if this is a copy or rename.
pub source: Option<(RepoPathBuf, CopyOperation)>,
/// The target path.
pub target: RepoPathBuf,
}
impl CopiesTreeDiffEntryPath {
/// The source path.
pub fn source(&self) -> &RepoPath {
self.source.as_ref().map_or(&self.target, |(path, _)| path)
}
/// The target path.
pub fn target(&self) -> &RepoPath {
&self.target
}
/// Whether this entry was copied or renamed from the source. Returns `None`
/// if the path is unchanged.
pub fn copy_operation(&self) -> Option<CopyOperation> {
self.source.as_ref().map(|(_, op)| *op)
}
}
/// Wraps a `TreeDiffStream`, adding support for copies and renames.
pub struct CopiesTreeDiffStream<'a> {
inner: TreeDiffStream<'a>,
source_tree: MergedTree,
target_tree: MergedTree,
copy_records: &'a CopyRecords,
}
impl<'a> CopiesTreeDiffStream<'a> {
/// Create a new diff stream with copy information.
pub fn new(
inner: TreeDiffStream<'a>,
source_tree: MergedTree,
target_tree: MergedTree,
copy_records: &'a CopyRecords,
) -> Self {
Self {
inner,
source_tree,
target_tree,
copy_records,
}
}
fn resolve_copy_source(
&self,
source: &RepoPath,
values: BackendResult<Diff<MergedTreeValue>>,
) -> BackendResult<(CopyOperation, Diff<MergedTreeValue>)> {
let target_value = values?.after;
let source_value = self.source_tree.path_value(source)?;
// If the source path is deleted in the target tree, it's a rename.
let source_value_at_target = self.target_tree.path_value(source)?;
let copy_op = if source_value_at_target.is_absent() || source_value_at_target.is_tree() {
CopyOperation::Rename
} else {
CopyOperation::Copy
};
Ok((copy_op, Diff::new(source_value, target_value)))
}
}
impl Stream for CopiesTreeDiffStream<'_> {
type Item = CopiesTreeDiffEntry;
fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
while let Some(diff_entry) = ready!(self.inner.as_mut().poll_next(cx)) {
let Some(CopyRecord { source, .. }) = self.copy_records.for_target(&diff_entry.path)
else {
let target_deleted =
matches!(&diff_entry.values, Ok(diff) if diff.after.is_absent());
if target_deleted && self.copy_records.has_source(&diff_entry.path) {
// Skip the "delete" entry when there is a rename.
continue;
}
return Poll::Ready(Some(CopiesTreeDiffEntry {
path: CopiesTreeDiffEntryPath {
source: None,
target: diff_entry.path,
},
values: diff_entry.values,
}));
};
let (copy_op, values) = match self.resolve_copy_source(source, diff_entry.values) {
Ok((copy_op, values)) => (copy_op, Ok(values)),
// Fall back to "copy" (= path still exists) if unknown.
Err(err) => (CopyOperation::Copy, Err(err)),
};
return Poll::Ready(Some(CopiesTreeDiffEntry {
path: CopiesTreeDiffEntryPath {
source: Some((source.clone(), copy_op)),
target: diff_entry.path,
},
values,
}));
}
Poll::Ready(None)
}
}