jj/lib/tests/test_view.rs
Martin von Zweigbergk f6a4cb57da repo: extract a Repo trait for Arc<ReadonlyRepo> and MutableRepo
This will soon replace the `RepoRef` enum, just like how the `Index`
trait replaced the `IndexRef` enum.
2023-02-15 19:15:17 -08:00

665 lines
25 KiB
Rust

// Copyright 2020 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.
use std::sync::Arc;
use jujutsu_lib::op_store::{BranchTarget, RefTarget, WorkspaceId};
use jujutsu_lib::repo::{ReadonlyRepo, Repo};
use jujutsu_lib::settings::UserSettings;
use jujutsu_lib::transaction::Transaction;
use maplit::{btreemap, hashset};
use test_case::test_case;
use testutils::{create_random_commit, write_random_commit, CommitGraphBuilder, TestRepo};
#[test_case(false ; "local backend")]
#[test_case(true ; "git backend")]
fn test_heads_empty(use_git: bool) {
let test_repo = TestRepo::init(use_git);
let repo = &test_repo.repo;
assert_eq!(
*repo.view().heads(),
hashset! {repo.store().root_commit_id().clone()}
);
assert_eq!(
*repo.view().public_heads(),
hashset! {repo.store().root_commit_id().clone()}
);
}
#[test_case(false ; "local backend")]
#[test_case(true ; "git backend")]
fn test_heads_fork(use_git: bool) {
let settings = testutils::user_settings();
let test_repo = TestRepo::init(use_git);
let repo = &test_repo.repo;
let mut tx = repo.start_transaction(&settings, "test");
let mut graph_builder = CommitGraphBuilder::new(&settings, tx.mut_repo());
let initial = graph_builder.initial_commit();
let child1 = graph_builder.commit_with_parents(&[&initial]);
let child2 = graph_builder.commit_with_parents(&[&initial]);
let repo = tx.commit();
assert_eq!(
*repo.view().heads(),
hashset! {
child1.id().clone(),
child2.id().clone(),
}
);
}
#[test_case(false ; "local backend")]
#[test_case(true ; "git backend")]
fn test_heads_merge(use_git: bool) {
let settings = testutils::user_settings();
let test_repo = TestRepo::init(use_git);
let repo = &test_repo.repo;
let mut tx = repo.start_transaction(&settings, "test");
let mut graph_builder = CommitGraphBuilder::new(&settings, tx.mut_repo());
let initial = graph_builder.initial_commit();
let child1 = graph_builder.commit_with_parents(&[&initial]);
let child2 = graph_builder.commit_with_parents(&[&initial]);
let merge = graph_builder.commit_with_parents(&[&child1, &child2]);
let repo = tx.commit();
assert_eq!(*repo.view().heads(), hashset! {merge.id().clone()});
}
#[test]
fn test_merge_views_heads() {
// Tests merging of the view's heads (by performing concurrent operations).
let settings = testutils::user_settings();
let test_repo = TestRepo::init(false);
let repo = &test_repo.repo;
let mut tx = repo.start_transaction(&settings, "test");
let mut_repo = tx.mut_repo();
let head_unchanged = write_random_commit(mut_repo, &settings);
let head_remove_tx1 = write_random_commit(mut_repo, &settings);
let head_remove_tx2 = write_random_commit(mut_repo, &settings);
let public_head_unchanged = write_random_commit(mut_repo, &settings);
mut_repo.add_public_head(&public_head_unchanged);
let public_head_remove_tx1 = write_random_commit(mut_repo, &settings);
mut_repo.add_public_head(&public_head_remove_tx1);
let public_head_remove_tx2 = write_random_commit(mut_repo, &settings);
mut_repo.add_public_head(&public_head_remove_tx2);
let repo = tx.commit();
let mut tx1 = repo.start_transaction(&settings, "test");
tx1.mut_repo().remove_head(head_remove_tx1.id());
tx1.mut_repo()
.remove_public_head(public_head_remove_tx1.id());
let head_add_tx1 = write_random_commit(tx1.mut_repo(), &settings);
let public_head_add_tx1 = write_random_commit(tx1.mut_repo(), &settings);
tx1.mut_repo().add_public_head(&public_head_add_tx1);
tx1.commit();
let mut tx2 = repo.start_transaction(&settings, "test");
tx2.mut_repo().remove_head(head_remove_tx2.id());
tx2.mut_repo()
.remove_public_head(public_head_remove_tx2.id());
let head_add_tx2 = write_random_commit(tx2.mut_repo(), &settings);
let public_head_add_tx2 = write_random_commit(tx2.mut_repo(), &settings);
tx2.mut_repo().add_public_head(&public_head_add_tx2);
tx2.commit();
let repo = repo.reload_at_head(&settings).unwrap();
let expected_heads = hashset! {
head_unchanged.id().clone(),
head_add_tx1.id().clone(),
head_add_tx2.id().clone(),
public_head_unchanged.id().clone(),
public_head_remove_tx1.id().clone(),
public_head_remove_tx2.id().clone(),
public_head_add_tx1.id().clone(),
public_head_add_tx2.id().clone(),
};
assert_eq!(repo.view().heads(), &expected_heads);
let expected_public_heads = hashset! {
public_head_unchanged.id().clone(),
public_head_add_tx1.id().clone(),
public_head_add_tx2.id().clone(),
};
assert_eq!(repo.view().public_heads(), &expected_public_heads);
}
#[test]
fn test_merge_views_checkout() {
// Tests merging of the view's checkout (by performing concurrent operations).
let settings = testutils::user_settings();
let test_repo = TestRepo::init(false);
let repo = &test_repo.repo;
// Workspace 1 gets updated in both transactions.
// Workspace 2 gets updated only in tx1.
// Workspace 3 gets updated only in tx2.
// Workspace 4 gets deleted in tx1 and modified in tx2.
// Workspace 5 gets deleted in tx2 and modified in tx1.
// Workspace 6 gets added in tx1.
// Workspace 7 gets added in tx2.
let mut initial_tx = repo.start_transaction(&settings, "test");
let commit1 = write_random_commit(initial_tx.mut_repo(), &settings);
let commit2 = write_random_commit(initial_tx.mut_repo(), &settings);
let commit3 = write_random_commit(initial_tx.mut_repo(), &settings);
let ws1_id = WorkspaceId::new("ws1".to_string());
let ws2_id = WorkspaceId::new("ws2".to_string());
let ws3_id = WorkspaceId::new("ws3".to_string());
let ws4_id = WorkspaceId::new("ws4".to_string());
let ws5_id = WorkspaceId::new("ws5".to_string());
let ws6_id = WorkspaceId::new("ws6".to_string());
let ws7_id = WorkspaceId::new("ws7".to_string());
initial_tx
.mut_repo()
.set_wc_commit(ws1_id.clone(), commit1.id().clone())
.unwrap();
initial_tx
.mut_repo()
.set_wc_commit(ws2_id.clone(), commit1.id().clone())
.unwrap();
initial_tx
.mut_repo()
.set_wc_commit(ws3_id.clone(), commit1.id().clone())
.unwrap();
initial_tx
.mut_repo()
.set_wc_commit(ws4_id.clone(), commit1.id().clone())
.unwrap();
initial_tx
.mut_repo()
.set_wc_commit(ws5_id.clone(), commit1.id().clone())
.unwrap();
let repo = initial_tx.commit();
let mut tx1 = repo.start_transaction(&settings, "test");
tx1.mut_repo()
.set_wc_commit(ws1_id.clone(), commit2.id().clone())
.unwrap();
tx1.mut_repo()
.set_wc_commit(ws2_id.clone(), commit2.id().clone())
.unwrap();
tx1.mut_repo().remove_wc_commit(&ws4_id);
tx1.mut_repo()
.set_wc_commit(ws5_id.clone(), commit2.id().clone())
.unwrap();
tx1.mut_repo()
.set_wc_commit(ws6_id.clone(), commit2.id().clone())
.unwrap();
tx1.commit();
let mut tx2 = repo.start_transaction(&settings, "test");
tx2.mut_repo()
.set_wc_commit(ws1_id.clone(), commit3.id().clone())
.unwrap();
tx2.mut_repo()
.set_wc_commit(ws3_id.clone(), commit3.id().clone())
.unwrap();
tx2.mut_repo()
.set_wc_commit(ws4_id.clone(), commit3.id().clone())
.unwrap();
tx2.mut_repo().remove_wc_commit(&ws5_id);
tx2.mut_repo()
.set_wc_commit(ws7_id.clone(), commit3.id().clone())
.unwrap();
// Make sure the end time different, assuming the clock has sub-millisecond
// precision.
std::thread::sleep(std::time::Duration::from_millis(1));
tx2.commit();
let repo = repo.reload_at_head(&settings).unwrap();
// We currently arbitrarily pick the first transaction's working-copy commit
// (first by transaction end time).
assert_eq!(repo.view().get_wc_commit_id(&ws1_id), Some(commit2.id()));
assert_eq!(repo.view().get_wc_commit_id(&ws2_id), Some(commit2.id()));
assert_eq!(repo.view().get_wc_commit_id(&ws3_id), Some(commit3.id()));
assert_eq!(repo.view().get_wc_commit_id(&ws4_id), None);
assert_eq!(repo.view().get_wc_commit_id(&ws5_id), None);
assert_eq!(repo.view().get_wc_commit_id(&ws6_id), Some(commit2.id()));
assert_eq!(repo.view().get_wc_commit_id(&ws7_id), Some(commit3.id()));
}
#[test]
fn test_merge_views_branches() {
// Tests merging of branches (by performing concurrent operations). See
// test_refs.rs for tests of merging of individual ref targets.
let settings = testutils::user_settings();
let test_repo = TestRepo::init(false);
let repo = &test_repo.repo;
let mut tx = repo.start_transaction(&settings, "test");
let mut_repo = tx.mut_repo();
let main_branch_local_tx0 = write_random_commit(mut_repo, &settings);
let main_branch_origin_tx0 = write_random_commit(mut_repo, &settings);
let main_branch_origin_tx1 = write_random_commit(mut_repo, &settings);
let main_branch_alternate_tx0 = write_random_commit(mut_repo, &settings);
mut_repo.set_local_branch(
"main".to_string(),
RefTarget::Normal(main_branch_local_tx0.id().clone()),
);
mut_repo.set_remote_branch(
"main".to_string(),
"origin".to_string(),
RefTarget::Normal(main_branch_origin_tx0.id().clone()),
);
mut_repo.set_remote_branch(
"main".to_string(),
"alternate".to_string(),
RefTarget::Normal(main_branch_alternate_tx0.id().clone()),
);
let feature_branch_local_tx0 = write_random_commit(mut_repo, &settings);
mut_repo.set_git_ref(
"feature".to_string(),
RefTarget::Normal(feature_branch_local_tx0.id().clone()),
);
let repo = tx.commit();
let mut tx1 = repo.start_transaction(&settings, "test");
let main_branch_local_tx1 = write_random_commit(tx1.mut_repo(), &settings);
tx1.mut_repo().set_local_branch(
"main".to_string(),
RefTarget::Normal(main_branch_local_tx1.id().clone()),
);
tx1.mut_repo().set_remote_branch(
"main".to_string(),
"origin".to_string(),
RefTarget::Normal(main_branch_origin_tx1.id().clone()),
);
let feature_branch_tx1 = write_random_commit(tx1.mut_repo(), &settings);
tx1.mut_repo().set_local_branch(
"feature".to_string(),
RefTarget::Normal(feature_branch_tx1.id().clone()),
);
tx1.commit();
let mut tx2 = repo.start_transaction(&settings, "test");
let main_branch_local_tx2 = write_random_commit(tx2.mut_repo(), &settings);
tx2.mut_repo().set_local_branch(
"main".to_string(),
RefTarget::Normal(main_branch_local_tx2.id().clone()),
);
tx2.mut_repo().set_remote_branch(
"main".to_string(),
"origin".to_string(),
RefTarget::Normal(main_branch_origin_tx1.id().clone()),
);
tx2.commit();
let repo = repo.reload_at_head(&settings).unwrap();
let expected_main_branch = BranchTarget {
local_target: Some(RefTarget::Conflict {
removes: vec![main_branch_local_tx0.id().clone()],
adds: vec![
main_branch_local_tx1.id().clone(),
main_branch_local_tx2.id().clone(),
],
}),
remote_targets: btreemap! {
"origin".to_string() => RefTarget::Normal(main_branch_origin_tx1.id().clone()),
"alternate".to_string() => RefTarget::Normal(main_branch_alternate_tx0.id().clone()),
},
};
let expected_feature_branch = BranchTarget {
local_target: Some(RefTarget::Normal(feature_branch_tx1.id().clone())),
remote_targets: btreemap! {},
};
assert_eq!(
repo.view().branches(),
&btreemap! {
"main".to_string() => expected_main_branch,
"feature".to_string() => expected_feature_branch,
}
);
}
#[test]
fn test_merge_views_tags() {
// Tests merging of tags (by performing concurrent operations). See
// test_refs.rs for tests of merging of individual ref targets.
let settings = testutils::user_settings();
let test_repo = TestRepo::init(false);
let repo = &test_repo.repo;
let mut tx = repo.start_transaction(&settings, "test");
let mut_repo = tx.mut_repo();
let v1_tx0 = write_random_commit(mut_repo, &settings);
mut_repo.set_tag("v1.0".to_string(), RefTarget::Normal(v1_tx0.id().clone()));
let v2_tx0 = write_random_commit(mut_repo, &settings);
mut_repo.set_tag("v2.0".to_string(), RefTarget::Normal(v2_tx0.id().clone()));
let repo = tx.commit();
let mut tx1 = repo.start_transaction(&settings, "test");
let v1_tx1 = write_random_commit(tx1.mut_repo(), &settings);
tx1.mut_repo()
.set_tag("v1.0".to_string(), RefTarget::Normal(v1_tx1.id().clone()));
let v2_tx1 = write_random_commit(tx1.mut_repo(), &settings);
tx1.mut_repo()
.set_tag("v2.0".to_string(), RefTarget::Normal(v2_tx1.id().clone()));
tx1.commit();
let mut tx2 = repo.start_transaction(&settings, "test");
let v1_tx2 = write_random_commit(tx2.mut_repo(), &settings);
tx2.mut_repo()
.set_tag("v1.0".to_string(), RefTarget::Normal(v1_tx2.id().clone()));
tx2.commit();
let repo = repo.reload_at_head(&settings).unwrap();
let expected_v1 = RefTarget::Conflict {
removes: vec![v1_tx0.id().clone()],
adds: vec![v1_tx1.id().clone(), v1_tx2.id().clone()],
};
let expected_v2 = RefTarget::Normal(v2_tx1.id().clone());
assert_eq!(
repo.view().tags(),
&btreemap! {
"v1.0".to_string() => expected_v1,
"v2.0".to_string() => expected_v2,
}
);
}
#[test]
fn test_merge_views_git_refs() {
// Tests merging of git refs (by performing concurrent operations). See
// test_refs.rs for tests of merging of individual ref targets.
let settings = testutils::user_settings();
let test_repo = TestRepo::init(false);
let repo = &test_repo.repo;
let mut tx = repo.start_transaction(&settings, "test");
let mut_repo = tx.mut_repo();
let main_branch_tx0 = write_random_commit(mut_repo, &settings);
mut_repo.set_git_ref(
"refs/heads/main".to_string(),
RefTarget::Normal(main_branch_tx0.id().clone()),
);
let feature_branch_tx0 = write_random_commit(mut_repo, &settings);
mut_repo.set_git_ref(
"refs/heads/feature".to_string(),
RefTarget::Normal(feature_branch_tx0.id().clone()),
);
let repo = tx.commit();
let mut tx1 = repo.start_transaction(&settings, "test");
let main_branch_tx1 = write_random_commit(tx1.mut_repo(), &settings);
tx1.mut_repo().set_git_ref(
"refs/heads/main".to_string(),
RefTarget::Normal(main_branch_tx1.id().clone()),
);
let feature_branch_tx1 = write_random_commit(tx1.mut_repo(), &settings);
tx1.mut_repo().set_git_ref(
"refs/heads/feature".to_string(),
RefTarget::Normal(feature_branch_tx1.id().clone()),
);
tx1.commit();
let mut tx2 = repo.start_transaction(&settings, "test");
let main_branch_tx2 = write_random_commit(tx2.mut_repo(), &settings);
tx2.mut_repo().set_git_ref(
"refs/heads/main".to_string(),
RefTarget::Normal(main_branch_tx2.id().clone()),
);
tx2.commit();
let repo = repo.reload_at_head(&settings).unwrap();
let expected_main_branch = RefTarget::Conflict {
removes: vec![main_branch_tx0.id().clone()],
adds: vec![main_branch_tx1.id().clone(), main_branch_tx2.id().clone()],
};
let expected_feature_branch = RefTarget::Normal(feature_branch_tx1.id().clone());
assert_eq!(
repo.view().git_refs(),
&btreemap! {
"refs/heads/main".to_string() => expected_main_branch,
"refs/heads/feature".to_string() => expected_feature_branch,
}
);
}
#[test]
fn test_merge_views_git_heads() {
// Tests merging of git heads (by performing concurrent operations). See
// test_refs.rs for tests of merging of individual ref targets.
let settings = testutils::user_settings();
let test_repo = TestRepo::init(false);
let repo = &test_repo.repo;
let mut tx0 = repo.start_transaction(&settings, "test");
let tx0_head = write_random_commit(tx0.mut_repo(), &settings);
tx0.mut_repo()
.set_git_head(RefTarget::Normal(tx0_head.id().clone()));
let repo = tx0.commit();
let mut tx1 = repo.start_transaction(&settings, "test");
let tx1_head = write_random_commit(tx1.mut_repo(), &settings);
tx1.mut_repo()
.set_git_head(RefTarget::Normal(tx1_head.id().clone()));
tx1.commit();
let mut tx2 = repo.start_transaction(&settings, "test");
let tx2_head = write_random_commit(tx2.mut_repo(), &settings);
tx2.mut_repo()
.set_git_head(RefTarget::Normal(tx2_head.id().clone()));
tx2.commit();
let repo = repo.reload_at_head(&settings).unwrap();
let expected_git_head = RefTarget::Conflict {
removes: vec![tx0_head.id().clone()],
adds: vec![tx1_head.id().clone(), tx2_head.id().clone()],
};
assert_eq!(repo.view().git_head(), Some(&expected_git_head));
}
fn commit_transactions(settings: &UserSettings, txs: Vec<Transaction>) -> Arc<ReadonlyRepo> {
let repo_loader = txs[0].base_repo().loader();
let mut op_ids = vec![];
for tx in txs {
op_ids.push(tx.commit().op_id().clone());
std::thread::sleep(std::time::Duration::from_millis(1));
}
let repo = repo_loader.load_at_head(settings).unwrap();
// Test the setup. The assumption here is that the parent order matches the
// order in which they were merged (which currently matches the transaction
// commit order), so we want to know make sure they appear in a certain
// order, so the caller can decide the order by passing them to this
// function in a certain order.
assert_eq!(*repo.operation().parent_ids(), op_ids);
repo
}
#[test]
fn test_merge_views_divergent() {
// We start with just commit A. Operation 1 rewrites it as A2. Operation 2
// rewrites it as A3.
let settings = testutils::user_settings();
let test_repo = TestRepo::init(false);
let mut tx = test_repo.repo.start_transaction(&settings, "test");
let commit_a = write_random_commit(tx.mut_repo(), &settings);
let repo = tx.commit();
let mut tx1 = repo.start_transaction(&settings, "test");
let commit_a2 = tx1
.mut_repo()
.rewrite_commit(&settings, &commit_a)
.set_description("A2")
.write()
.unwrap();
tx1.mut_repo().rebase_descendants(&settings).unwrap();
let mut tx2 = repo.start_transaction(&settings, "test");
let commit_a3 = tx2
.mut_repo()
.rewrite_commit(&settings, &commit_a)
.set_description("A3")
.write()
.unwrap();
tx2.mut_repo().rebase_descendants(&settings).unwrap();
let repo = commit_transactions(&settings, vec![tx1, tx2]);
// A2 and A3 should be heads.
assert_eq!(
*repo.view().heads(),
hashset! {commit_a2.id().clone(), commit_a3.id().clone()}
);
}
#[test_case(false ; "rewrite first")]
#[test_case(true ; "add child first")]
fn test_merge_views_child_on_rewritten(child_first: bool) {
// We start with just commit A. Operation 1 adds commit B on top. Operation 2
// rewrites A as A2.
let settings = testutils::user_settings();
let test_repo = TestRepo::init(false);
let mut tx = test_repo.repo.start_transaction(&settings, "test");
let commit_a = write_random_commit(tx.mut_repo(), &settings);
let repo = tx.commit();
let mut tx1 = repo.start_transaction(&settings, "test");
let commit_b = create_random_commit(tx1.mut_repo(), &settings)
.set_parents(vec![commit_a.id().clone()])
.write()
.unwrap();
let mut tx2 = repo.start_transaction(&settings, "test");
let commit_a2 = tx2
.mut_repo()
.rewrite_commit(&settings, &commit_a)
.set_description("A2")
.write()
.unwrap();
tx2.mut_repo().rebase_descendants(&settings).unwrap();
let repo = if child_first {
commit_transactions(&settings, vec![tx1, tx2])
} else {
commit_transactions(&settings, vec![tx2, tx1])
};
// A new B2 commit (B rebased onto A2) should be the only head.
let heads = repo.view().heads();
assert_eq!(heads.len(), 1);
let b2_id = heads.iter().next().unwrap();
let commit_b2 = repo.store().get_commit(b2_id).unwrap();
assert_eq!(commit_b2.change_id(), commit_b.change_id());
assert_eq!(commit_b2.parent_ids(), vec![commit_a2.id().clone()]);
}
#[test_case(false, false ; "add child on unchanged, rewrite first")]
#[test_case(false, true ; "add child on unchanged, add child first")]
#[test_case(true, false ; "add child on rewritten, rewrite first")]
#[test_case(true, true ; "add child on rewritten, add child first")]
fn test_merge_views_child_on_rewritten_divergent(on_rewritten: bool, child_first: bool) {
// We start with divergent commits A2 and A3. Operation 1 adds commit B on top
// of A2 or A3. Operation 2 rewrites A2 as A4. The result should be that B
// gets rebased onto A4 if it was based on A2 before, but if it was based on
// A3, it should remain there.
let settings = testutils::user_settings();
let test_repo = TestRepo::init(false);
let mut tx = test_repo.repo.start_transaction(&settings, "test");
let commit_a2 = write_random_commit(tx.mut_repo(), &settings);
let commit_a3 = create_random_commit(tx.mut_repo(), &settings)
.set_change_id(commit_a2.change_id().clone())
.write()
.unwrap();
let repo = tx.commit();
let mut tx1 = repo.start_transaction(&settings, "test");
let parent = if on_rewritten { &commit_a2 } else { &commit_a3 };
let commit_b = create_random_commit(tx1.mut_repo(), &settings)
.set_parents(vec![parent.id().clone()])
.write()
.unwrap();
let mut tx2 = repo.start_transaction(&settings, "test");
let commit_a4 = tx2
.mut_repo()
.rewrite_commit(&settings, &commit_a2)
.set_description("A4")
.write()
.unwrap();
tx2.mut_repo().rebase_descendants(&settings).unwrap();
let repo = if child_first {
commit_transactions(&settings, vec![tx1, tx2])
} else {
commit_transactions(&settings, vec![tx2, tx1])
};
if on_rewritten {
// A3 should remain as a head. The other head should be B2 (B rebased onto A4).
let mut heads = repo.view().heads().clone();
assert_eq!(heads.len(), 2);
assert!(heads.remove(commit_a3.id()));
let b2_id = heads.iter().next().unwrap();
let commit_b2 = repo.store().get_commit(b2_id).unwrap();
assert_eq!(commit_b2.change_id(), commit_b.change_id());
assert_eq!(commit_b2.parent_ids(), vec![commit_a4.id().clone()]);
} else {
// No rebases should happen, so B and A4 should be the heads.
let mut heads = repo.view().heads().clone();
assert_eq!(heads.len(), 2);
assert!(heads.remove(commit_b.id()));
assert!(heads.remove(commit_a4.id()));
}
}
#[test_case(false ; "abandon first")]
#[test_case(true ; "add child first")]
fn test_merge_views_child_on_abandoned(child_first: bool) {
// We start with commit B on top of commit A. Operation 1 adds commit C on top.
// Operation 2 abandons B.
let settings = testutils::user_settings();
let test_repo = TestRepo::init(false);
let mut tx = test_repo.repo.start_transaction(&settings, "test");
let commit_a = write_random_commit(tx.mut_repo(), &settings);
let commit_b = create_random_commit(tx.mut_repo(), &settings)
.set_parents(vec![commit_a.id().clone()])
.write()
.unwrap();
let repo = tx.commit();
let mut tx1 = repo.start_transaction(&settings, "test");
let commit_c = create_random_commit(tx1.mut_repo(), &settings)
.set_parents(vec![commit_b.id().clone()])
.write()
.unwrap();
let mut tx2 = repo.start_transaction(&settings, "test");
tx2.mut_repo()
.record_abandoned_commit(commit_b.id().clone());
tx2.mut_repo().rebase_descendants(&settings).unwrap();
let repo = if child_first {
commit_transactions(&settings, vec![tx1, tx2])
} else {
commit_transactions(&settings, vec![tx2, tx1])
};
// A new C2 commit (C rebased onto A) should be the only head.
let heads = repo.view().heads();
assert_eq!(heads.len(), 1);
let id_c2 = heads.iter().next().unwrap();
let commit_c2 = repo.store().get_commit(id_c2).unwrap();
assert_eq!(commit_c2.change_id(), commit_c.change_id());
assert_eq!(commit_c2.parent_ids(), vec![commit_a.id().clone()]);
}