防止 git apply 删除旧文件

Question

我有两个文件 a 和 b，每个文件都包含它们的名称。我创建了一个这样的补丁：

git diff a b > test.patch

现在在应用补丁时，文件a被删除：

git apply test.patch

有没有办法防止git在创建或应用补丁时删除文件？

Answer 1

git diff 用法的语法是

git diff [--no-index] <path> <path>

在您的情况下，--no-index 是隐式假定的。因此，命令

git diff a b

假设b 是文件a 的更新版本。运行您的命令会生成一个如下所示的补丁：

$ git diff --no-index 123.txt 456.txt
diff --git a/123.txt b/456.txt
index 97f93f4..9fa0bac 100644
--- a/123.txt
+++ b/456.txt
@@ -1 +1 @@
-123.txt
+456.txt

如果您尝试对超过 2 个文件执行此操作，则会出现错误：

$ git diff -- 123.txt 456.txt 789.txt
Not a git repository
To compare two paths outside a working tree:
usage: git diff [--no-index] <path> <path>

$ git diff --no-index 123.txt 456.txt 789.txt
usage: git diff --no-index <path> <path>

一种解决方法（假设您要创建一个同时添加了a 和b 的补丁）是在一个临时目录中创建一个新的git repo。您可以使用

创建一个没有文件的初始提交

git commit --allow-empty -m "Initial"

并将文件a 和b 复制到。

运行git add --all 后，git diff --staged > test.patch 将创建一个适当的补丁，如下所示：

diff --git a/123.txt b/123.txt
new file mode 100644
index 0000000..97f93f4
--- /dev/null
+++ b/123.txt
@@ -0,0 +1 @@
+123.txt
diff --git a/456.txt b/456.txt
new file mode 100644
index 0000000..9fa0bac
--- /dev/null
+++ b/456.txt
@@ -0,0 +1 @@
+456.txt
diff --git a/789.txt b/789.txt
new file mode 100644
index 0000000..a25ef22
--- /dev/null
+++ b/789.txt
@@ -0,0 +1 @@
+789.txt