jj_lib/
commit_builder.rs

1// Copyright 2020 The Jujutsu Authors
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7// https://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15#![expect(missing_docs)]
16
17use std::sync::Arc;
18
19use pollster::FutureExt as _;
20
21use crate::backend;
22use crate::backend::BackendError;
23use crate::backend::BackendResult;
24use crate::backend::ChangeId;
25use crate::backend::CommitId;
26use crate::backend::MergedTreeId;
27use crate::backend::Signature;
28use crate::commit::Commit;
29use crate::commit::is_backend_commit_empty;
30use crate::repo::MutableRepo;
31use crate::repo::Repo;
32use crate::settings::JJRng;
33use crate::settings::SignSettings;
34use crate::settings::UserSettings;
35use crate::signing::SignBehavior;
36use crate::store::Store;
37
38#[must_use]
39pub struct CommitBuilder<'repo> {
40    mut_repo: &'repo mut MutableRepo,
41    inner: DetachedCommitBuilder,
42}
43
44impl CommitBuilder<'_> {
45    /// Detaches from `&'repo mut` lifetime. The returned builder can be used in
46    /// order to obtain a temporary commit object.
47    pub fn detach(self) -> DetachedCommitBuilder {
48        self.inner
49    }
50
51    /// Clears the source commit to not record new commit as rewritten from it.
52    ///
53    /// The caller should also assign new change id to not create divergence.
54    pub fn clear_rewrite_source(mut self) -> Self {
55        self.inner.clear_rewrite_source();
56        self
57    }
58
59    pub fn parents(&self) -> &[CommitId] {
60        self.inner.parents()
61    }
62
63    pub fn set_parents(mut self, parents: Vec<CommitId>) -> Self {
64        self.inner.set_parents(parents);
65        self
66    }
67
68    pub fn predecessors(&self) -> &[CommitId] {
69        self.inner.predecessors()
70    }
71
72    pub fn set_predecessors(mut self, predecessors: Vec<CommitId>) -> Self {
73        self.inner.set_predecessors(predecessors);
74        self
75    }
76
77    pub fn tree_id(&self) -> &MergedTreeId {
78        self.inner.tree_id()
79    }
80
81    pub fn set_tree_id(mut self, tree_id: MergedTreeId) -> Self {
82        self.inner.set_tree_id(tree_id);
83        self
84    }
85
86    /// [`Commit::is_empty()`] for the new commit.
87    pub fn is_empty(&self) -> BackendResult<bool> {
88        self.inner.is_empty(self.mut_repo)
89    }
90
91    pub fn change_id(&self) -> &ChangeId {
92        self.inner.change_id()
93    }
94
95    pub fn set_change_id(mut self, change_id: ChangeId) -> Self {
96        self.inner.set_change_id(change_id);
97        self
98    }
99
100    pub fn generate_new_change_id(mut self) -> Self {
101        self.inner.generate_new_change_id();
102        self
103    }
104
105    pub fn description(&self) -> &str {
106        self.inner.description()
107    }
108
109    pub fn set_description(mut self, description: impl Into<String>) -> Self {
110        self.inner.set_description(description);
111        self
112    }
113
114    pub fn author(&self) -> &Signature {
115        self.inner.author()
116    }
117
118    pub fn set_author(mut self, author: Signature) -> Self {
119        self.inner.set_author(author);
120        self
121    }
122
123    pub fn committer(&self) -> &Signature {
124        self.inner.committer()
125    }
126
127    pub fn set_committer(mut self, committer: Signature) -> Self {
128        self.inner.set_committer(committer);
129        self
130    }
131
132    /// [`Commit::is_discardable()`] for the new commit.
133    pub fn is_discardable(&self) -> BackendResult<bool> {
134        self.inner.is_discardable(self.mut_repo)
135    }
136
137    pub fn sign_settings(&self) -> &SignSettings {
138        self.inner.sign_settings()
139    }
140
141    pub fn set_sign_behavior(mut self, sign_behavior: SignBehavior) -> Self {
142        self.inner.set_sign_behavior(sign_behavior);
143        self
144    }
145
146    pub fn set_sign_key(mut self, sign_key: String) -> Self {
147        self.inner.set_sign_key(sign_key);
148        self
149    }
150
151    pub fn clear_sign_key(mut self) -> Self {
152        self.inner.clear_sign_key();
153        self
154    }
155
156    pub fn write(self) -> BackendResult<Commit> {
157        self.inner.write(self.mut_repo)
158    }
159
160    /// Records the old commit as abandoned instead of writing new commit. This
161    /// is noop for the builder created by [`MutableRepo::new_commit()`].
162    pub fn abandon(self) {
163        self.inner.abandon(self.mut_repo);
164    }
165}
166
167/// Like `CommitBuilder`, but doesn't mutably borrow `MutableRepo`.
168#[derive(Debug)]
169pub struct DetachedCommitBuilder {
170    store: Arc<Store>,
171    rng: Arc<JJRng>,
172    commit: backend::Commit,
173    rewrite_source: Option<Commit>,
174    sign_settings: SignSettings,
175}
176
177impl DetachedCommitBuilder {
178    /// Only called from [`MutableRepo::new_commit`]. Use that function instead.
179    pub(crate) fn for_new_commit(
180        repo: &dyn Repo,
181        settings: &UserSettings,
182        parents: Vec<CommitId>,
183        tree_id: MergedTreeId,
184    ) -> Self {
185        let store = repo.store().clone();
186        let signature = settings.signature();
187        assert!(!parents.is_empty());
188        let rng = settings.get_rng();
189        let change_id = rng.new_change_id(store.change_id_length());
190        let commit = backend::Commit {
191            parents,
192            predecessors: vec![],
193            root_tree: tree_id,
194            change_id,
195            description: String::new(),
196            author: signature.clone(),
197            committer: signature,
198            secure_sig: None,
199        };
200        Self {
201            store,
202            rng,
203            commit,
204            rewrite_source: None,
205            sign_settings: settings.sign_settings(),
206        }
207    }
208
209    /// Only called from [`MutableRepo::rewrite_commit`]. Use that function
210    /// instead.
211    pub(crate) fn for_rewrite_from(
212        repo: &dyn Repo,
213        settings: &UserSettings,
214        predecessor: &Commit,
215    ) -> Self {
216        let store = repo.store().clone();
217        let mut commit = backend::Commit::clone(predecessor.store_commit());
218        commit.predecessors = vec![predecessor.id().clone()];
219        commit.committer = settings.signature();
220        // If the user had not configured a name and email before but now they have,
221        // update the author fields with the new information.
222        if commit.author.name.is_empty()
223            || commit.author.name == UserSettings::USER_NAME_PLACEHOLDER
224        {
225            commit.author.name.clone_from(&commit.committer.name);
226        }
227        if commit.author.email.is_empty()
228            || commit.author.email == UserSettings::USER_EMAIL_PLACEHOLDER
229        {
230            commit.author.email.clone_from(&commit.committer.email);
231        }
232
233        // Reset author timestamp on discardable commits if the author is the
234        // committer. While it's unlikely we'll have somebody else's commit
235        // with no description in our repo, we'd like to be extra safe.
236        if commit.author.name == commit.committer.name
237            && commit.author.email == commit.committer.email
238            && predecessor.is_discardable(repo).unwrap_or_default()
239        {
240            commit.author.timestamp = commit.committer.timestamp;
241        }
242
243        Self {
244            store,
245            commit,
246            rng: settings.get_rng(),
247            rewrite_source: Some(predecessor.clone()),
248            sign_settings: settings.sign_settings(),
249        }
250    }
251
252    /// Attaches the underlying `mut_repo`.
253    pub fn attach(self, mut_repo: &mut MutableRepo) -> CommitBuilder<'_> {
254        assert!(Arc::ptr_eq(&self.store, mut_repo.store()));
255        CommitBuilder {
256            mut_repo,
257            inner: self,
258        }
259    }
260
261    /// Clears the source commit to not record new commit as rewritten from it.
262    ///
263    /// The caller should also assign new change id to not create divergence.
264    pub fn clear_rewrite_source(&mut self) {
265        self.rewrite_source = None;
266    }
267
268    pub fn parents(&self) -> &[CommitId] {
269        &self.commit.parents
270    }
271
272    pub fn set_parents(&mut self, parents: Vec<CommitId>) -> &mut Self {
273        assert!(!parents.is_empty());
274        self.commit.parents = parents;
275        self
276    }
277
278    pub fn predecessors(&self) -> &[CommitId] {
279        &self.commit.predecessors
280    }
281
282    pub fn set_predecessors(&mut self, predecessors: Vec<CommitId>) -> &mut Self {
283        self.commit.predecessors = predecessors;
284        self
285    }
286
287    pub fn tree_id(&self) -> &MergedTreeId {
288        &self.commit.root_tree
289    }
290
291    pub fn set_tree_id(&mut self, tree_id: MergedTreeId) -> &mut Self {
292        self.commit.root_tree = tree_id;
293        self
294    }
295
296    /// [`Commit::is_empty()`] for the new commit.
297    pub fn is_empty(&self, repo: &dyn Repo) -> BackendResult<bool> {
298        is_backend_commit_empty(repo, &self.store, &self.commit)
299    }
300
301    pub fn change_id(&self) -> &ChangeId {
302        &self.commit.change_id
303    }
304
305    pub fn set_change_id(&mut self, change_id: ChangeId) -> &mut Self {
306        self.commit.change_id = change_id;
307        self
308    }
309
310    pub fn generate_new_change_id(&mut self) -> &mut Self {
311        self.commit.change_id = self.rng.new_change_id(self.store.change_id_length());
312        self
313    }
314
315    pub fn description(&self) -> &str {
316        &self.commit.description
317    }
318
319    pub fn set_description(&mut self, description: impl Into<String>) -> &mut Self {
320        self.commit.description = description.into();
321        self
322    }
323
324    pub fn author(&self) -> &Signature {
325        &self.commit.author
326    }
327
328    pub fn set_author(&mut self, author: Signature) -> &mut Self {
329        self.commit.author = author;
330        self
331    }
332
333    pub fn committer(&self) -> &Signature {
334        &self.commit.committer
335    }
336
337    pub fn set_committer(&mut self, committer: Signature) -> &mut Self {
338        self.commit.committer = committer;
339        self
340    }
341
342    /// [`Commit::is_discardable()`] for the new commit.
343    pub fn is_discardable(&self, repo: &dyn Repo) -> BackendResult<bool> {
344        Ok(self.description().is_empty() && self.is_empty(repo)?)
345    }
346
347    pub fn sign_settings(&self) -> &SignSettings {
348        &self.sign_settings
349    }
350
351    pub fn set_sign_behavior(&mut self, sign_behavior: SignBehavior) -> &mut Self {
352        self.sign_settings.behavior = sign_behavior;
353        self
354    }
355
356    pub fn set_sign_key(&mut self, sign_key: String) -> &mut Self {
357        self.sign_settings.key = Some(sign_key);
358        self
359    }
360
361    pub fn clear_sign_key(&mut self) -> &mut Self {
362        self.sign_settings.key = None;
363        self
364    }
365
366    /// Writes new commit and makes it visible in the `mut_repo`.
367    pub fn write(self, mut_repo: &mut MutableRepo) -> BackendResult<Commit> {
368        let predecessors = self.commit.predecessors.clone();
369        let commit = write_to_store(&self.store, self.commit, &self.sign_settings)?;
370        // FIXME: Google's index.has_id() always returns true.
371        if mut_repo.is_backed_by_default_index() && mut_repo.index().has_id(commit.id()) {
372            // Recording existing commit as new would create cycle in
373            // predecessors/parent mappings within the current transaction, and
374            // in predecessors graph globally.
375            return Err(BackendError::Other(
376                format!("Newly-created commit {id} already exists", id = commit.id()).into(),
377            ));
378        }
379        mut_repo.add_head(&commit)?;
380        mut_repo.set_predecessors(commit.id().clone(), predecessors);
381        if let Some(rewrite_source) = self.rewrite_source {
382            mut_repo.set_rewritten_commit(rewrite_source.id().clone(), commit.id().clone());
383        }
384        Ok(commit)
385    }
386
387    /// Writes new commit without making it visible in the repo.
388    ///
389    /// This does not consume the builder, so you can reuse the current
390    /// configuration to create another commit later.
391    pub fn write_hidden(&self) -> BackendResult<Commit> {
392        write_to_store(&self.store, self.commit.clone(), &self.sign_settings)
393    }
394
395    /// Records the old commit as abandoned in the `mut_repo`.
396    ///
397    /// This is noop if there's no old commit that would be rewritten to the new
398    /// commit by `write()`.
399    pub fn abandon(self, mut_repo: &mut MutableRepo) {
400        let commit = self.commit;
401        if let Some(rewrite_source) = &self.rewrite_source {
402            mut_repo
403                .record_abandoned_commit_with_parents(rewrite_source.id().clone(), commit.parents);
404        }
405    }
406}
407
408fn write_to_store(
409    store: &Arc<Store>,
410    mut commit: backend::Commit,
411    sign_settings: &SignSettings,
412) -> BackendResult<Commit> {
413    let should_sign = store.signer().can_sign() && sign_settings.should_sign(&commit);
414    let sign_fn = |data: &[u8]| store.signer().sign(data, sign_settings.key.as_deref());
415
416    // Commit backend doesn't use secure_sig for writing and enforces it with an
417    // assert, but sign_settings.should_sign check above will want to know
418    // if we're rewriting a signed commit
419    commit.secure_sig = None;
420
421    store
422        .write_commit(commit, should_sign.then_some(&mut &sign_fn))
423        .block_on()
424}
jj_lib/commit_builder.rs

jj_lib/
commit_builder.rs
