我們把在Git里常用的一些名詞做了解釋列在這里。這些名詞(terms)全部來自[Git Glossary](http://www.kernel.org/pub/software/scm/git/docs/gitglossary.html)。 _alternate object database_ > Via the alternates mechanism, a repository > > ~~~ > can inherit part of its object database > from another object database, which is called "alternate". > > ~~~ _bare repository_ > A bare repository is normally an appropriately > > ~~~ > named directory with a `.git` suffix that does not > have a locally checked-out copy of any of the files under > revision control. That is, all of the `git` > administrative and control files that would normally be present in the > hidden `.git` sub-directory are directly present in the > `repository.git` directory instead, > and no other files are present and checked out. Usually publishers of > public repositories make bare repositories available. > > ~~~ _祼倉庫_ > ~~~ > A bare repository is normally an appropriately > named directory with a `.git` suffix that does not > have a locally checked-out copy of any of the files under > revision control. That is, all of the `git` > administrative and control files that would normally be present in the > hidden `.git` sub-directory are directly present in the > `repository.git` directory instead, > and no other files are present and checked out. Usually publishers of > public repositories make bare repositories available. > > ~~~ _blob object（二進制對象）_ > 沒有類型的數據對象。例如：一個文件的內容。 _branch_ > A "branch" is an active line of development. The most recent > > ~~~ > commit on a branch is referred to as the tip of > that branch. The tip of the branch is referenced by a branch > head, which moves forward as additional development > is done on the branch. A single git > repository can track an arbitrary number of > branches, but your working tree is > associated with just one of them (the "current" or "checked out" > branch), and HEAD points to that branch. > > ~~~ _分支_ > ~~~ > 一個“分支”是開發過程中的(active line)。。。。 > > ~~~ _cache（緩存）_ > 索引(index)的舊稱(obsolete). _chain（鏈表）_ > 一串對象，其中每個對象都有指向其后繼對象的引用(reference to its successor)。例如：一個提交(commit)的后繼對象就是它的父對象。 _changeset（修改集）_ > BitKeeper/cvsps 里對于提交(commit)的說法。但是 git 只存儲快照(states)，不存儲修改；所以這個詞用在 git 里有點不大合適。 _checkout（簽出）_ > ~~~ > 用對象倉庫(object database)里的一個樹對象(tree object)更新當前整個工作樹(worktree)，或者一個二進制對象(blob object)更新工作樹的一部分；如果工作樹指向了一個新的分支，那么就會更新索引(index)和HEAD。 > > ~~~ _cherry-picking_ > In SCM jargon, "cherry pick" means to choose a subset of > > ~~~ > changes out of a series of changes (typically commits) and record them > as a new series of changes on top of a different codebase. In GIT, this is > performed by the "git cherry-pick" command to extract the change introduced > by an existing commit and to record it based on the tip > of the current branch as a new commit. > > ~~~ _cherry-picking_ > 在SCM的行話里，“cherry pick“ 意味著從一系列的修改中選出一部分修改(通常是提交)，應用到當前代碼中。() _clean（干凈）_ > 如果一個工作樹(working tree)中所有的修改都已提交到了當前分支里(current head)，那么就說它是干凈的(clean)，反之它就是臟的(dirty)。 _commit_ > As a verb: The action of storing a new snapshot of the project's > > ~~~ > state in the git history, by creating a new commit representing the current > state of the index and advancing HEAD > to point at the new commit. > > ~~~ _commit（提交）_ > 作為名詞：指向git歷史的某一點的指針；整個項目的歷史就由一組相互關聯的提交組成的。提交(commit)在其它版本控制系統中也做"revision"或"version"。同時做為提交對象(commit object)的縮寫。 > > 作為動詞：創建一新的提交(commit)來表示當前索引(index)的狀態的行為，把 HEAD 指向新創建的提交，這一系列把項目在某一時間上的快照(snapshot)保存在git歷史中的操作。 _提交對象_ > 一個關于特定版本信息(particular revision)的對象。包括父對象名，提交者，作者，日期和存儲了此版本內容的樹對象名(tree object)。 _core git_ > Git的基本數據結構和工具，它只對外提供簡單的代碼管理工具。 _DAG_ > 有向無環圖。眾多提交對象(commit objects)組成了一個有向無環圖；因為它們都有直接父對象(direct parent)，且沒有一條提交線路(chain)的起點和終點都是同一個對象。 _dangling object（懸空對象）_ > 一個甚至從其它不可達對象也不可達的對象(unreachable object)；倉庫里的一個懸空對象沒有任何引用(reference)或是對象(object)引用它。 _detached HEAD（分離的HEAD）_ > 通常情況下HEAD里是存放當前分支的名字。然而 git 有時也允許你簽出任意的一個提交(commit)，而不一定是某分支的最近的提交(the tip of any particular branch)；在這種情況下，HEAD就是處于分離的狀態(detached)。 譯者注：這時`.git/HEAD`中存儲的就是簽出的提交的SHA串值。 _dircache_ > 請參見索引(index)。 _directory（目錄）_ > 執行"ls"命令所顯示的結果 :-) _dirty（臟）_ > 一個工作樹里有沒有提交到當前分支里修改，那么我就說它是臟的(dirty)。 _ent_ > 某些人給樹名(tree-ish)起的另外一個別名，這里`http://en.wikipedia.org/wiki/Ent_(Middle-earth)`有更詳細的解釋。最好不要使用這個名詞，以免讓大家糊涂。 _evil merge（壞的合并）_ > 如果一次合并引入一些不存在于任何父對象(parent)中的修改，那么就稱它是一個壞的合并(evil merge)。 _fast forward_ > A fast-forward is a special type of merge where you have a > > ~~~ > revision and you are "merging" another > branch's changes that happen to be a descendant of what > you have. In such these cases, you do not make a new merge > commit but instead just update to his > revision. This will happen frequently on a > tracking branch of a remote > repository. > > ~~~ _快速向前_ > “fast-forward”是一種特殊的合并,()。 在這種情況下，并沒有創建一個合并提交(merge commit)，只是更新了版本信息。 當本地分支是遠端倉庫(remote repository)的跟蹤分支時，這種情況經常出現。 _fetch（抓取）_ > 抓取一個分支意味著：得到遠端倉庫(remote repository)分支的head ref，找出本地對象數據庫所缺少的對象，并把它們下載下來。你可以參考一下?[git fetch](http://www.kernel.org/pub/software/scm/git/docs/git-fetch.html)。 _file system（文件系統）_ > Linus Torvalds 最初設計 git 時，是把它設計成一個在用戶空間(user space)運行的文件系統；也就是一個用來保存文件和目錄的 infrastructure，這樣就保證了git的速度和效率。 _git archive_ > 對玩架構的人來說，這就是倉庫的同義詞。 _grafts_ > Grafts enables two otherwise different lines of development to be joined > > ~~~ > together by recording fake ancestry information for commits. This way > you can make git pretend the set of parents a commit has > is different from what was recorded when the commit was > created. Configured via the `.git/info/grafts` file. > > ~~~ _hash（哈希）_ > 在git里，這就是對象名(object name)的同義詞。 _head_ > 指向一個分支最新提交的命名引用(named reference)。除非使用了打包引用(packed refs)，heads 一般存儲在`$GIT_DIR/refs/heads/`。 參見:?[git pack-refs](http://www.kernel.org/pub/software/scm/git/docs/git-pack-refs.html) _HEAD_ > 當前分支。詳細的講是：你的工作樹(working tree)通是從HEAD所指向的tree所派生的來的。 HEAD 必須是指向一個你倉庫里的head，除非你使用分離的HEAD(detached HEAD)。 _head ref_ > head的同義詞。 _hook_ > During the normal execution of several git commands, call-outs are made > > ~~~ > to optional scripts that allow a developer to add functionality or > checking. Typically, the hooks allow for a command to be pre-verified > and potentially aborted, and allow for a post-notification after the > operation is done. The hook scripts are found in the > `$GIT_DIR/hooks/` directory, and are enabled by simply > removing the `.sample` suffix from the filename. In earlier versions > of git you had to make them executable. > > ~~~ _鉤子_ > 在一些git命令的執行過程中, () 允許開發人員調用特別的腳本來添加功能或檢查。 > > ~~~ > () > > ~~~ ~~~ Typically，鉤子允許對一個命令做pre-verified并且可以中止此命令的運行；同時也可在這個命令執行完后做后繼的通知工作。這些鉤子腳本放在`$GIT_DIR/hooks/`目錄下，你只要把這它們文件名的`.sample`后綴刪掉就可以了。不過在git的早期版本，你需要為這些鉤子腳本加上可執行屬性。 ~~~ _index_ > A collection of files with stat information, whose contents are stored > > ~~~ > as objects. The index is a stored version of your > working tree. Truth be told, it can also contain a second, and even > a third version of a working tree, which are used > when merging. > > ~~~ _索引_ > 描述項目狀態信息的文件，。索引里保存的是你的工作樹的版本記錄。() _index entry_ > The information regarding a particular file, stored in the > > ~~~ > index. An index entry can be unmerged, if a > merge was started, but not yet finished (i.e. if > the index contains multiple versions of that file). > > ~~~ _索引條目_ _主分支 (master)_ > 默認的開發分支。當你創建了一個git倉庫，一個叫"master"的分支就被創建并且成為當前活動分支(active branch)。在多數情況下，這個分支里就包含有本地的開發內容。 _merge_ > As a verb: To bring the contents of another > > ~~~ > branch (possibly from an external > repository) into the current branch. In the > case where the merged-in branch is from a different repository, > this is done by first fetching the remote branch > and then merging the result into the current branch. This > combination of fetch and merge operations is called a > pull. Merging is performed by an automatic process > that identifies changes made since the branches diverged, and > then applies all those changes together. In cases where changes > conflict, manual intervention may be required to complete the > merge. > > ~~~ _merge（合并）_ > 作為動詞：把另外一個分支(也許來自另外一個倉庫)的內容合并進當前的分支。() > > 作為名詞：除非合并的結果是 fast forward；那么一次成功的合并會創建一個新的提交(commit)來表示這次合并，并且把合并了的分支做為此提交(commit)的父對象。這個提交(commit)也可以表述為“合并提交”(merge commit)，或者就是"合并"(merge 名詞)。 _object（對象）_ > Git的存儲單位，它以對象內容的SHA1值做為唯一對象名；因此對象內容是不能被修改的。 _object database（對象倉庫）_ > 用來存儲一組對象(objects)，每個對象通過對象名來區別。對象(objects)通常保存在?`$GIT_DIR/objects/`。 _object identifier（對象標識符）_ > 對象名(object name)的同義詞。 _object name（對象名）_ > 一個對象的唯一標識符(unique identifier)。它是使用SHA1算法(Secure Hash Algorithm 1)給對象內容進行哈希(hash)計算，產生的一個40個字節長的16進制編碼的串。 _object type（對象類型）_ > Git有4種對象類型：提交(commit)，樹(tree)，標簽(tag)和二進制塊(blob)。 _octopus（章魚）_ > 一次多于兩個分支的合并(merge)。也用來表示聰明的肉食動物。 _origin_ > 默認的上游倉庫(upstream repository)。每個項目至少有一個它追蹤(track)的上游(upstream)倉庫，通常情況 origin 就是用來表示它。你可以用 ”｀git branch -r`“ 命令查看上游倉庫(upstream repository)里所有的分支，再用 origin/name-of-upstream-branch 的名字來抓取(fetch)遠程追蹤分支里的內容。 _pack（包）_ > 一個文件，里面有一些壓縮了的對象。(用以節約空間或是提高傳輸效率)。 _pack index（包索引）_ > 包(pack)里的一些標識符和其它相關信息，用于幫助git快速的訪問包(pack)里面的對象。 _parent_ > A commit object contains a (possibly empty) list > > ~~~ > of the logical predecessor(s) in the line of development, i.e. its > parents. > > ~~~ _父對象_ > 一個提交對象(commit object)，()。 _pickaxe_ > The term pickaxe refers to an option to the diffcore > > ~~~ > routines that help select changes that add or delete a given text > string. With the `--pickaxe-all` option, it can be used to view the full > changeset that introduced or removed, say, a > particular line of text. See git diff. > > ~~~ _plumbing_ > core git的別名(cute name)。 _porcelain_ > Cute name for programs and program suites depending on > > ~~~ > core git, presenting a high level access to > core git. Porcelains expose more of a SCM > interface than the plumbing. > > ~~~ _pull（拉）_ > 拉(pull)一個分支意味著，把它抓取(fetch)下來并合并(merge)進當前的分支。可以參考?[git pull](http://www.kernel.org/pub/software/scm/git/docs/git-pull.html). _push_ > Pushing a branch means to get the branch's > > ~~~ > head ref from a remote repository, > find out if it is a direct ancestor to the branch's local > head ref, and in that case, putting all > objects, which are reachable from the local > head ref, and which are missing from the remote > repository, into the remote > object database, and updating the remote > head ref. If the remote head is not an > ancestor to the local head, the push fails. > > ~~~ _推_ > () _reachable_ > All of the ancestors of a given commit are said to be > > ~~~ > "reachable" from that commit. More > generally, one object is reachable from > another if we can reach the one from the other by a chain > that follows tags to whatever they tag, > commits to their parents or trees, and > trees to the trees or blobs > that they contain. > > ~~~ > > _可達的_ _rebase_ > 重新應用(reapply)當前點(branch)和另一個點(base)間的修改；并且根據rebase的結果重置當前分支的 head。 譯者注：這個功能可以修改歷史提交。 _ref（引用）_ > 一個40字節長的SHA1串或是表示某個對象的名字。它們可能存儲在?`$GIT_DIR/refs/`。 _reflog_ > reflog用以表示本地的ref的歷史記錄。從另外一角度也可以說，它能行告訴你這個倉庫最近的第3個版本(revision)是什么，還可以告訴你昨天晚上9點14分時你是在這個倉庫的哪個分支下工作。可以參見:[git reflog](http://www.kernel.org/pub/software/scm/git/docs/git-reflog.html)。 _refspec_ > "refspec"用于描述在抓取和推的過程中，遠程ref和本地ref之間的映射關系。它用冒號連接：:，前面也可以加一個加號：“+“。 例如：`git fetch $URL refs/heads/master:refs/heads/origin`?意味著：從$URL抓取主分支的 head 并把它保存到本地的origin分支的head中。`git push $URL refs/heads/master:refs/heads/to-upstream`?意味著：把我本地主分支 head 推到$URL上的 to-upstream分支里。具體可以參見：?[git push](http://www.kernel.org/pub/software/scm/git/docs/git-push.html)。 _repository_ > A collection of refs together with an > > ~~~ > object database containing all objects > which are reachable from the refs, possibly > accompanied by meta data from one or more porcelains. A > repository can share an object database with other repositories > via alternates mechanism. > > ~~~ _resolve_ > 在自動合并失敗后，手工修復合并沖突的行為。 _revision（版本）_ > 對象倉庫(object database)保存的文件和目錄在某一特定時間點的狀態；它會被一個提交對象(commit object)所引用。 _rewind_ > 丟棄某一部分開發成果。例如：把head 指向早期的版本。 _SCM_ > 源代碼管理工作。 _SHA1_ > 對象名(object name)的同義詞。 _shallow repository_ > A shallow repository has an incomplete > > ~~~ > history some of whose commits have parents cauterized away (in other > words, git is told to pretend that these commits do not have the > parents, even though they are recorded in the commit > object). This is sometimes useful when you are interested only in the > recent history of a project even though the real history recorded in the > upstream is much larger. A shallow repository > is created by giving the `--depth` option to git clone, and > its history can be later deepened with git fetch. > > ~~~ _symref_ > Symbolic reference: instead of containing the SHA1 > > ~~~ > id itself, it is of the format 'ref: refs/some/thing' and when > referenced, it recursively dereferences to this reference. > 'HEAD' is a prime example of a symref. Symbolic > references are manipulated with the git symbolic-ref > command. > > ~~~ _tag（標簽）_ > 一個ref指向一個標簽或提交對象。與 head 相反，標簽并不會在一次提交操作后改變。標簽(不是標簽對象)存儲在`$GIT_DIR/refs/tags/`。 一個標簽通常是用來標識提交家族鏈(commit ancerstry chain)里的某一點。 _tag object（標簽對象）_ > 一個含有指向其它對象的引用(ref)的對象，對象里包括注釋消息。如果它里面可以含有一個PGP簽名，那么就稱為一個“簽名標簽對象”(signed tag object)。 _topic branch_ > A regular git branch that is used by a developer to > > ~~~ > identify a conceptual line of development. Since branches are very easy > and inexpensive, it is often desirable to have several small branches > that each contain very well defined concepts or small incremental yet > related changes. > > ~~~ _tracking branch_ > A regular git branch that is used to follow changes from > > ~~~ > another repository. A tracking > branch should not contain direct modifications or have local commits > made to it. A tracking branch can usually be > identified as the right-hand-side ref in a Pull: > > ~~~ ~~~ refspec. ~~~ _追蹤分支_ > 一個用以追蹤(follow)另外一個倉庫的修改的git分支。() _tree（樹）_ > 可以是一個工作樹(working tree)，也可以是一個樹對象(tree object)。 _tree object（樹對象）_ > 包含有一串(list)文件名和模式(mode)，并且指向與之相關的二進制對象(blob object)和樹對象(tree object)。一個樹(tree)等價于一個目錄。 _tree-ish（樹名）_ > 一個指向的提交對象(commit object)，樹對象(tree object)或是標簽對象(tag object)的引用(ref)。 _unmerged index（未合并索引）_ > 一個索引中包含有未合并的索引條目(index entries)。 _unreachable object（不可達對象）_ > 從任何一個分支、標簽或是其它引用(reference)做為起點都無法到達的一個對象。 _working tree（工作樹）_ > 簽出(checkout)用于編輯的文件目錄樹。 工作樹一般等價于 HEAD 加本地沒有提交的修改。