Navigating through files in a repository can sometimes be tricky, especially when dealing with absolute paths. One effective way to utilize the git show command with absolute paths is by first determining the path to the worktree of your repository. This can be done using the command git rev-parse --show-toplevel. This command returns the absolute path to the root directory of your git repository.
Once you have the worktree path, you can compute the relative path of your file. Here’s a simple script to demonstrate this:
filepath=$1
worktree=$(git rev-parse --show-toplevel)
relpath=$(realpath -s --relative-to="$worktree" "$filepath")
git show -C "$worktree" HEAD^:"$relpath"
In this script, the first line retrieves the absolute path of the file you want to inspect. Next, the worktree variable stores the path to the repository's root, and the relpath variable computes the relative path from the worktree to your specified file. Finally, the git show command is executed with the calculated relative path.
If you need to access a revision other than HEAD^, you can modify the script to take the revision and file path as two separate arguments. This flexibility allows you to explore different versions of your files without hassle.
It’s important to understand why the notation <revision>:<path> may not behave as expected when using absolute paths. This notation is more of a low-level way to reference items within a tree structure in your repository. For instance, if you input this format into commands like git rev-parse or git cat-file, you can retrieve the hash, type, and content of the specified blob or subtree:
$ git rev-parse HEAD:path/to/file
7bb43a8cc90a1accbb6a167f9ed7c62af3f15b92
$ git cat-file -t HEAD:path/to/file
blob
$ git cat-file -p HEAD:path/to/file
-- ... content ... --
This method is not limited to commits; any tree can be referenced. For example:
$ git rev-parse HEAD:path/to
eacf32b...
$ git rev-parse eacf32b:file.txt
7bb43a8c..
The conversion of the string <revision>:<path> into a git object ID is one of the initial actions performed when using commands like git show. The system simply looks at the paths that exist within the git database.
For further details on these commands, you can refer to the official documentation: git rev-parse and git cat-file.