我可以从 git 分支中删除多少文件？

Question

Therearemanythreads 在 SO 关于跟踪不同分支中的不同文件。由于 git 也简化了部署，人们尝试将特定于部署的秘密文件添加到内部分支中，并且会出现这些线程中讨论的问题。一种可能的suggested 解决方案是使用submodule。我宁愿避免它。因此，通过扩展this method 制作了一个脚本，让我可以合并一个私有分支，而无需考虑.branchownfiles 中列出的秘密文件的更改。

看起来效果不错，但提出一个关于在 git 中删除文件的问题：git merge 抱怨从 private 合并到 master 时删除的文件，即使此文件从未参与过与 @987654332 相关的提交@: "文件在 HEAD 中删除，私下修改"

这是你可以看到的过程：

i@my % git init
Initialized empty Git repository in /here/there/.git/
i@my % echo 'hello' > 'start.txt'
i@my % git add start.txt
i@my % git commit -m 'started'
[master (root-commit) 32d41f5] started
 1 file changed, 1 insertion(+)
 create mode 100644 start.txt

i@my % git checkout -b private
Switched to a new branch 'private'
i@my % echo 'this is secret' > a_secret.txt
i@my % echo a_secret.txt > .branchownfiles
i@my % echo .branchownfiles >> .branchownfiles
i@my % git add a_secret.txt
i@my % git add .branchownfiles
i@my % git commit -m 'a secret file added'
[private c2e174f] a secret file added
 2 files changed, 3 insertions(+)
 create mode 100644 .branchownfiles
 create mode 100644 a_secret.txt

i@my % git checkout master
Switched to branch 'master'
i@my % git-merge-with-care.sh private
Automatic merge went well; stopped before committing as requested
rm '.branchownfiles'
rm 'a_secret.txt'
Success
# this is basically a `git merge` followed by two `git rm` for two files.
# so i suppose .branchownfiles and a_secret.txt never should leave anything in `master`
# but my assumption is not true..
i@my % git commit
[master 916c14b] Merge branch 'private'

i@my % git checkout private
Switched to branch 'private'
i@my % echo 'changed in private, should change in public too' > start.txt
i@my % echo 'secret changed too' > a_secret.txt
i@my % git add -u
i@my % git commit -m 'secret changed'
[private dc8938a] secret changed
 2 files changed, 2 insertions(+), 2 deletions(-)

i@my % git checkout master
Switched to branch 'master'
i@my % git-merge-with-care.sh private
# now my question arise.
CONFLICT (modify/delete): a_secret.txt deleted in HEAD and modified in private. Version private of a_secret.txt left in tree.
# git merge complains about a_secret.txt an knows it deleted in HEAD. Why?!
Automatic merge failed; fix conflicts and then commit the result.
Trying to fix conflicts for branch limited files
a_secret.txt: [b]
Remerge with ours strategy
CONFLICT (modify/delete): a_secret.txt deleted in HEAD and modified in private. Version private of a_secret.txt left in tree.
Automatic merge failed; fix conflicts and then commit the result.
a_secret.txt: needs merge
rm 'a_secret.txt'
Success

我的脚本仍然有效，因为它在合并之前删除了这些文件。但我想知道为什么 git 会想起 a_secret.txt 虽然它从来没有在这个分支的提交中？有没有办法以某种方式实现git merge --no-commit 后跟git rm 的效果 git 从不记得这些删除的文件以前在这里？我的意思是git merge，但能够将一些文件添加到索引目录。

我的方法安全吗？如果我 git rm 一些文件并且 git 后来回忆这些文件以前在这里，git 仍然有一些关于这些文件的信息。什么样的数据，它在哪里？有人可以通过她对master 分支的访问权限找到a_secret.txt 的内容吗？

这是我的git-merge-with-care.sh：

#!/bin/env zsh

ls -d .git 2>/dev/null 1>&2
if [ $? != 0 ]; then
    echo "error: run this from root of project"
    exit 1
fi

if [ $# != 1 ]; then
    echo "usage: $0 <private branch>"
    exit 1
fi

current_branch=$(git branch -q | sed -n -e 's/^* //p')
from_branch=$1 #private branch
into_branch=master #public branch

if [ $current_branch != $into_branch ]; then
    echo "error: merge while out of $into_branch branch"
    exit 1
fi

new_files=$(git diff -z --name-only --diff-filter=A $into_branch $from_branch)
changed_files=$(git diff -z --name-only --diff-filter='M|T' $into_branch $from_branch)
branch_files=$(git show $from_branch:.branchownfiles)
git merge --no-commit --no-ff $from_branch

# fix conflict with strategy
if [ $? != 0 ]; then
    echo "Trying to fix conflicts for branch limited files"
    failing=false
    git diff -z --name-only --diff-filter=U  | while IFS= read -r -d $'\0' f; do
        { grep -x -q "$f" <<<"$branch_files" && echo "$f: [b]"; } || { [ $f != ".branchownfiles" ] && echo "$f: [!]" && failing=true; }
    done
    git merge --abort
    if $failing; then
        echo "Merge aborted because of merge conflicts"
        exit 2
    else
        echo "Remerge with ours strategy"
        git merge --no-commit $from_branch -s recursive -X ours --no-ff
        if [ $? != 0 ]; then
            # conflits for deleted files in merger but added again from mergee
            conflicting_files=$(git diff -z --name-only --diff-filter=U)
            # echo "$conflicting_files" | sort
            # echo "$new_files" | sort

            if grep -q "$(echo \"$conflicting_files\" | sort -z)" <<<"$(echo \"$new_files\" | sort -z)"; then
                xargs -0 <<<"$conflicting_files" -I'{}' git rm --ignore-unmatch '{}'
                [[ x`git diff --diff-filter=U` == 'x' ]] || exit 5
            fi
        fi
    fi
fi

# remove files added from private branch but are restricted to private branch
xargs -0 -I'{}' <<<$new_files sh -c "grep -x -q '{}' <<<\"$branch_files\" && [ -e '{}' ] && git rm -rf '{}'"

# bring back public files overwritten bye private branch data
xargs -0 -I'{}' <<<"$changed_files" sh -c "grep -x -q '{}' <<<\"$branch_files\" && git checkout HEAD '{}'"
echo "Success"
exit 0

Answer 1

当您合并两个分支时，这两个提交都可以从合并提交中访问。因此，如果您有权访问 master，则可以在合并之前秘密访问所有内容。这也是git认为文件被删除的原因。

如果我签出那个 repo 并且只得到 master 分支，你可以做 git checkout master^2 并且你实际上是在什么是秘密分支。

尝试运行git merge-base master private。它将给出“添加的秘密文件”提交。该提交和主文件之间的差异之一是主文件（a_secret、.branchownfiles）上丢失的文件。所以 git 东西他们必须在 master 上被删除，因为那个提交是 master 的祖先。这是真的。这就是信息的来源。