如何查找具有特定父级的所有提交？

Question

我该如何查找一个具有特定父级的存储库中的所有提交？

例如，如果我有一个提交 A，我想找到所有与 A 共享父级的其他提交。在LibGit2Sharp中，最有效、性能最佳且正确的方法是什么？

- Tower

Answer 1

这是一个棘手的问题;-)

Git对象允许检索提交的父级。然而，找到提交的子级并不容易。

以下代码将“部分”解决此问题。思路是从存储库的所有引用（头、标签等）执行git log，并在此过程中选择每个具有所请求SHA的父项的提交。

由于遍历是从最近提交开始沿着祖先路径向下进行的，如果您正在搜索具有非常大的历史记录和许多分支的存储库中非常早期的提交的子级，则可能需要一些时间。

[Fact]
public void CanRetrieveChildrenOfASpecificCommit()
{
    TemporaryCloneOfTestRepo path = BuildTemporaryCloneOfTestRepo(StandardTestRepoPath);
    using (var repo = new Repository(path.RepositoryPath))
    {
        const string parentSha = "5b5b025afb0b4c913b4c338a42934a3863bf3644";

        var filter = new Filter
                         {
                             /* Revwalk from all the refs (git log --all) ... */
                             Since = repo.Refs, 

                             /* ... and stop when the parent is reached */
                             Until = parentSha
                         };

        var commits = repo.Commits.QueryBy(filter);

        var children = from c in commits
                    from p in c.Parents
                    let pId = p.Id
                    where pId.Sha == parentSha
                    select c;

        var expectedChildren = new[] { "c47800c7266a2be04c571c04d5a6614691ea99bd", 
                                        "4a202b346bb0fb0db7eff3cffeb3c70babbd2045" };

        Assert.Equal(expectedChildren, children.Select(c => c.Id.Sha));
    }
}

限制：

• 本方法无法检索已经被重写的提交记录（例如通过修订或变基），因为LibGit2Sharp目前还没有公开访问引用日志的方法。
• 此操作也无法检索不可达（悬空）提交记录。

测试仓库：

被查询仓库的内容如下所示：

$ git log --all --graph
* commit 4c062a6361ae6959e06292c1fa5e2822d9c96345
| Author: gor <[e-mail]>
| Date:   Thu Apr 14 18:44:16 2011 +0300
|
|     directory was added
|
*   commit be3563ae3f795b2b4353bcce3a527ad0a4f7f644
|\  Merge: 9fd738e c47800c
| | Author: Scott Chacon <[e-mail]>
| | Date:   Tue May 25 11:58:27 2010 -0700
| |
| |     Merge branch 'br2'
| |
| | * commit e90810b8df3e80c413d903f631643c716887138d
| | | Author: Vicent Marti <[e-mail]>
| | | Date:   Thu Aug 5 18:42:20 2010 +0200
| | |
| | |     Test commit 2
| | |
| | * commit 6dcf9bf7541ee10456529833502442f385010c3d
| |   Author: Vicent Marti <[e-mail]>
| |   Date:   Thu Aug 5 18:41:33 2010 +0200
| |
| |       Test commit 1
| |
| | *   commit a4a7dce85cf63874e984719f4fdd239f5145052f
| | |\  Merge: c47800c 9fd738e
| |/ /  Author: Scott Chacon <[e-mail]>
| | /   Date:   Tue May 25 12:00:23 2010 -0700
| |/
|/|         Merge branch 'master' into br2
| |
* | commit 9fd738e8f7967c078dceed8190330fc8648ee56a
| | Author: Scott Chacon <[e-mail]>
| | Date:   Mon May 24 10:19:19 2010 -0700
| |
| |     a fourth commit
| |
* | commit 4a202b346bb0fb0db7eff3cffeb3c70babbd2045
| | Author: Scott Chacon <[e-mail]>
| | Date:   Mon May 24 10:19:04 2010 -0700
| |
| |     a third commit
| |
| * commit c47800c7266a2be04c571c04d5a6614691ea99bd
|/  Author: Scott Chacon <[e-mail]>
|   Date:   Tue May 25 11:58:14 2010 -0700
|
|       branch commit one
|
* commit 5b5b025afb0b4c913b4c338a42934a3863bf3644
| Author: Scott Chacon <[e-mail]>
| Date:   Tue May 11 13:38:42 2010 -0700
|
|     another commit
|
* commit 8496071c1b46c854b31185ea97743be6a8774479
  Author: Scott Chacon <[e-mail]>
  Date:   Sat May 8 16:13:06 2010 -0700

      testing

* commit 41bc8c69075bbdb46c5c6f0566cc8cc5b46e8bd9
| Author: Scott Chacon <[e-mail]>
| Date:   Tue May 11 13:40:41 2010 -0700
|
|     packed commit two
|
* commit 5001298e0c09ad9c34e4249bc5801c75e9754fa5
  Author: Scott Chacon <[e-mail]>
  Date:   Tue May 11 13:40:23 2010 -0700

      packed commit one

- nulltoken

---

过滤器已经发生了变化，您可以在这里看到 - https://github.com/libgit2/libgit2sharp/blob/f8e2d42ed9051fa5a5348c1a13d006f0cc069bc7/LibGit2Sharp.Tests/CommitFixture.cs#L861 - Orn Kristjansson

对于一个足够小的代码仓库来说，只需将git log --all --graph的结果导出到一个文本文件中，然后通过搜索来查找所需的SHA值，这本身就是一个可行的策略！ - undefined

Answer 2

这对我有用（将$CHILD_COMMIT替换为您实际的提交）：

for commit in `git rev-list --all`; do echo "$commit <- `git log --pretty=%P -n 1 $commit`" | grep $CHILD_COMMIT; done

它将查找所有引用，其中提交是以child <- parent1 parent2...格式的子代或父代

- Alexey Martemyanov