-
Notifications
You must be signed in to change notification settings - Fork 322
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
This is not meant to be merged in this form.
I am bashing everything on the head with a large bat, until it works.
Once everything works nicely in this draft, I will break it up into
smaller tested pieces that are intended to be merged.
* Grab current heads and build a set of [(Parent, Child)...]
* Start a transaction.
* Fetch in the transaction:
It's extremely important to fetch *all* branches from *all* remotes.
This is because if we don't fetch all branches, when we start rebasing,
a root branch may be merged upstream with contents of a branch we didn't
fetch, so we end up with conflicts. It's safest to always fetch all branches
and then only rebase what we need.
* Grab current heads on transaction:
* Transaction MutableRepo should be updated after fetch.
* Build a Map where old heads are the keys and the new heads are values.
* If old == new, skip it.
* This way if nothing changed, we end up with an empty map and avoid bugs
downstream (index.is_ancestor returns true if old == new).
* Relationship is figured out by index.is_ancestor(old_head_id, new_head_id) in a loop.
* Check if rebase is needed.
* old_heads.set_diffence(new_heads) gives old heads that are no longer heads, which would
mean, their descendants need to be rebased.
* Find children needing rebase:
* Build list of rebase specs with: (commit, new_parent)
* commit is the immdiate child of old_heads needing rebase.
* call repo_mut.transform_descendants with a rewritter closure.
* simplify_merge
* rewrite commits matching the rebase_specs
* for all other commits, if any new_parents match old_heads in our old -> new mapping,
update those to point at the updated heads.
* rebase with emptying newly emptied commits.
Issue: #1039- Loading branch information
Showing
4 changed files
with
336 additions
and
0 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,302 @@ | ||
| use std::collections::BTreeMap; | ||
| use std::collections::BTreeSet; | ||
| use std::fmt; | ||
|
|
||
| use itertools::Itertools; | ||
| use jj_lib::backend::CommitId; | ||
| use jj_lib::commit::Commit; | ||
| use jj_lib::repo::Repo; | ||
| use jj_lib::revset::FailingSymbolResolver; | ||
| use jj_lib::revset::RevsetExpression; | ||
| use jj_lib::revset::RevsetIteratorExt; | ||
| use jj_lib::rewrite::EmptyBehaviour; | ||
| use jj_lib::str_util::StringPattern; | ||
|
|
||
| use crate::cli_util::short_change_hash; | ||
| use crate::cli_util::short_commit_hash; | ||
| use crate::cli_util::CommandHelper; | ||
| use crate::cli_util::WorkspaceCommandTransaction; | ||
| use crate::commands::CommandError; | ||
| use crate::git_util::get_fetch_remotes; | ||
| use crate::git_util::get_git_repo; | ||
| use crate::git_util::git_fetch; | ||
| use crate::git_util::FetchArgs; | ||
| use crate::ui::Ui; | ||
|
|
||
| /// Sync the local JJ repo to specified Git remote branch(es). | ||
| /// | ||
| /// The sync command will first fetch from the Git remote, then | ||
| /// rebase all local changes onto the appropriate updated | ||
| /// heads that were fetched. | ||
| /// | ||
| /// Changes that are made empty by the rebase are dropped. | ||
| #[derive(clap::Args, Clone, Debug)] | ||
| pub struct GitSyncArgs { | ||
| #[command(flatten)] | ||
| fetch: FetchArgs, | ||
| } | ||
|
|
||
| pub fn cmd_git_sync( | ||
| ui: &mut Ui, | ||
| command: &CommandHelper, | ||
| args: &GitSyncArgs, | ||
| ) -> Result<(), CommandError> { | ||
| let mut workspace_command = command.workspace_helper(ui)?; | ||
|
|
||
| let git_repo = get_git_repo(workspace_command.repo().store())?; | ||
| let remotes = get_fetch_remotes( | ||
| ui, | ||
| command.settings(), | ||
| &git_repo, | ||
| &FetchArgs { | ||
| branch: vec![StringPattern::everything()], | ||
| remotes: vec![], | ||
| all_remotes: true, | ||
| }, | ||
| )?; | ||
|
|
||
| let remote_patterns = remotes | ||
| .iter() | ||
| .map(|p| StringPattern::Exact(p.to_string())) | ||
| .collect_vec(); | ||
|
|
||
| let mut tx = workspace_command.start_transaction(); | ||
|
|
||
| let old_heads = get_branch_heads(tx.repo(), &args.fetch.branch)?; | ||
| let parent_child_pairs = | ||
| get_parent_child_commit_pairs(tx.repo(), &old_heads, &args.fetch.branch, &remote_patterns)?; | ||
|
|
||
| // prep to git fetch | ||
| git_fetch( | ||
| ui, | ||
| &mut tx, | ||
| &git_repo, | ||
| &FetchArgs { | ||
| branch: vec![StringPattern::everything()], | ||
| remotes: remotes.clone(), | ||
| all_remotes: true, | ||
| }, | ||
| )?; | ||
|
|
||
| // is rebase needed? | ||
| let updated_heads = get_branch_heads(tx.repo(), &args.fetch.branch)?; | ||
| let new_heads = BTreeSet::from_iter(updated_heads.iter().cloned()) | ||
| .difference(&BTreeSet::from_iter(old_heads.iter().cloned())) | ||
| .cloned() | ||
| .collect_vec(); | ||
| if new_heads.is_empty() { | ||
| // rebase not needed | ||
| tx.finish(ui, "sync completed; no rebase".to_string())?; | ||
| return Ok(()); | ||
| } | ||
|
|
||
| // find rebase targets | ||
| let needs_rebase = BTreeSet::from_iter(old_heads.iter().cloned()) | ||
| .difference(&BTreeSet::from_iter(updated_heads.iter().cloned())) | ||
| .cloned() | ||
| .collect_vec(); | ||
|
|
||
| let old_to_new = map_old_to_new_heads(&tx, &needs_rebase[..], &new_heads[..])?; | ||
|
|
||
| let rebase_specs = parent_child_pairs | ||
| .iter() | ||
| .filter_map(|pair| { | ||
| if needs_rebase.contains(&pair.parent) { | ||
| old_to_new.get(pair.parent.id()).map(|new| RebaseSpec { | ||
| commit: pair.child.id().clone(), | ||
| new_parent: new.clone(), | ||
| }) | ||
| } else { | ||
| None | ||
| } | ||
| }) | ||
| .collect_vec(); | ||
|
|
||
| let settings = tx.settings().clone(); | ||
| let mut num_rebased = 0; | ||
|
|
||
| tx.repo_mut().transform_descendants( | ||
| &settings, | ||
| rebase_specs | ||
| .iter() | ||
| .map(|spec| spec.commit.clone()) | ||
| .collect::<Vec<_>>(), | ||
| |mut rewriter| { | ||
| rewriter.simplify_ancestor_merge(); | ||
| for spec in &rebase_specs { | ||
| // move children of updated branches to the latest branch head | ||
| if rewriter.old_commit().id() == &spec.commit { | ||
| rewriter.set_new_parents(vec![spec.new_parent.clone()]); | ||
| } else { | ||
| // if new parents point at old heads, update them to point | ||
| // at the updated heads. | ||
| let mut updated_parents: Vec<CommitId> = vec![]; | ||
|
|
||
| let old_parents = rewriter.new_parents().iter().cloned().collect_vec(); | ||
|
|
||
| for parent in &old_parents { | ||
| if let Some(updated) = maybe_update_commit( | ||
| rewriter.repo(), | ||
| parent, | ||
| &new_heads.iter().map(|c| c.id().clone()).collect_vec(), | ||
| ) { | ||
| updated_parents.push(updated.clone()); | ||
| } else { | ||
| updated_parents.push(parent.clone()); | ||
| } | ||
| } | ||
|
|
||
| rewriter.set_new_parents(updated_parents); | ||
| } | ||
| } | ||
|
|
||
| if let Some(builder) = | ||
| rewriter.rebase_with_empty_behavior(&settings, EmptyBehaviour::AbandonNewlyEmpty)? | ||
| { | ||
| builder.write()?; | ||
| num_rebased += 1; | ||
| } | ||
|
|
||
| Ok(()) | ||
| }, | ||
| )?; | ||
|
|
||
| tx.finish( | ||
| ui, | ||
| format!("sync completed; {num_rebased} commits rebased to new heads"), | ||
| )?; | ||
|
|
||
| Ok(()) | ||
| } | ||
|
|
||
| fn get_branch_heads( | ||
| repo: &dyn Repo, | ||
| branches: &[StringPattern], | ||
| ) -> Result<Vec<Commit>, CommandError> { | ||
| let mut commits: Vec<Commit> = vec![]; | ||
|
|
||
| for branch in branches { | ||
| let mut branch_commits: Vec<Commit> = RevsetExpression::bookmarks(branch.clone()) | ||
| .resolve_user_expression(repo, &FailingSymbolResolver)? | ||
| .evaluate(repo)? | ||
| .iter() | ||
| .commits(repo.store()) | ||
| .try_collect()?; | ||
|
|
||
| commits.append(&mut branch_commits); | ||
| } | ||
|
|
||
| Ok(commits) | ||
| } | ||
|
|
||
| fn maybe_update_commit( | ||
| repo: &dyn Repo, | ||
| commit: &CommitId, | ||
| new_heads: &[CommitId], | ||
| ) -> Option<CommitId> { | ||
| new_heads | ||
| .iter() | ||
| .filter_map(|new| { | ||
| if new != commit && repo.index().is_ancestor(commit, new) { | ||
| Some(new.clone()) | ||
| } else { | ||
| None | ||
| } | ||
| }) | ||
| .next() | ||
| } | ||
|
|
||
| fn map_old_to_new_heads( | ||
| tx: &WorkspaceCommandTransaction, | ||
| old_heads: &[Commit], | ||
| new_heads: &[Commit], | ||
| ) -> Result<BTreeMap<CommitId, CommitId>, CommandError> { | ||
| let mut out: BTreeMap<CommitId, CommitId> = BTreeMap::from([]); | ||
| let index = tx.repo().index(); | ||
| for new in new_heads { | ||
| for old in old_heads { | ||
| if old != new && index.is_ancestor(old.id(), new.id()) { | ||
| out.insert(old.id().clone(), new.id().clone()); | ||
| } | ||
| } | ||
| } | ||
|
|
||
| Ok(out) | ||
| } | ||
|
|
||
| fn format_commit(commit: &Commit) -> String { | ||
| let change_hash = short_change_hash(commit.change_id()); | ||
| let commit_hash = short_commit_hash(commit.id()); | ||
|
|
||
| format!("{commit_hash}:{change_hash}") | ||
| } | ||
|
|
||
| #[derive(Eq, Ord, PartialEq, PartialOrd)] | ||
| pub struct CommitPair { | ||
| parent: Commit, | ||
| child: Commit, | ||
| } | ||
|
|
||
| impl fmt::Display for CommitPair { | ||
| fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { | ||
| let parent = format_commit(&self.parent); | ||
| let child = format_commit(&self.child); | ||
| write!(f, "=> {parent} --> {child}") | ||
| } | ||
| } | ||
|
|
||
| pub struct RebaseSpec { | ||
| commit: CommitId, | ||
| new_parent: CommitId, | ||
| } | ||
|
|
||
| fn get_parent_child_commit_pairs( | ||
| repo: &dyn Repo, | ||
| start: &[Commit], | ||
| branches: &[StringPattern], | ||
| remotes: &[StringPattern], | ||
| ) -> Result<Vec<CommitPair>, CommandError> { | ||
| let store = repo.store(); | ||
| let mut pairs: Vec<CommitPair> = vec![]; | ||
|
|
||
| for commit in start { | ||
| for parent_id in commit.parent_ids() { | ||
| pairs.push(CommitPair { | ||
| parent: store.get_commit(parent_id)?, | ||
| child: commit.clone(), | ||
| }); | ||
| } | ||
| } | ||
|
|
||
| let start = start.iter().map(|c| c.id().clone()).collect_vec(); | ||
|
|
||
| for remote in remotes { | ||
| for branch in branches { | ||
| let commits: Vec<Commit> = RevsetExpression::commits(start.clone()) | ||
| .descendants() | ||
| .minus(&RevsetExpression::commits(start.clone())) | ||
| .minus(&RevsetExpression::remote_bookmarks( | ||
| branch.clone(), | ||
| remote.clone(), | ||
| None, | ||
| )) | ||
| .resolve_user_expression(repo, &FailingSymbolResolver)? | ||
| .evaluate(repo)? | ||
| .iter() | ||
| .commits(repo.store()) | ||
| .try_collect()?; | ||
|
|
||
| for commit in commits { | ||
| for parent_id in commit.parent_ids() { | ||
| pairs.push(CommitPair { | ||
| parent: store.get_commit(parent_id)?, | ||
| child: commit.clone(), | ||
| }); | ||
| } | ||
| } | ||
| } | ||
| } | ||
|
|
||
| pairs.sort(); | ||
| Ok(pairs) | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters