"Open File" in a branch gives you the current file

[Dagur]

Describe the bug

Sometimes I want to view a file as it was when it was commited but currently it's not possible because lazygit always opens the file directly from the file system (i.e. the active branch).

To Reproduce
Steps to reproduce the behavior:

1. Let's say that the active branch is main.
2. View any other branch under Local Branches
3. Open a commit and highlight a file.
4. If you press o (Open File), an editor will open with the contents of the file on main, not the version that belongs to that commit.

Expected behavior
I want to see how the file looked when it was committed.

Version info:
Run lazygit --version and paste the result here
commit=4e38a941de3baf9e50d3fd5432933d6efccff091, build date=2025-02-25T11:24:06Z, build source=binaryRelease, version=0.47.2, os=linux, arch=amd64, git version=2.45.2

Run git --version and paste the result here
git version 2.45.2

Additional context
This might be by design, and if that's the case then look at this as a feature request :)

[ChrisMcD1]

Hm, interesting idea.

Here's what the code beneath the o command looks like:

lazygit/pkg/gui/controllers/helpers/files_helper.go

Lines 81 to 91 in 4e38a94

	func (self *FilesHelper) OpenFile(filename string) error {
	absPath, err := filepath.Abs(filename)
	if err != nil {
	return err
	}
	self.c.LogAction(self.c.Tr.Actions.OpenFile)
	if err := self.c.OS().OpenFile(absPath); err != nil {
	return err
	}
	return nil
	}

As you can see, we really just say "open this file" (inside of the OS helper we handle things like people's desired editor).

Now, we could easily pass down the context about the commit sha that the user requested, but I'm not aware of an easy way to open that file without also checking out that commit as a detached head, and I think people would be surprised to have their working directory changes auto-stashed, and potentially then have conflicts, just because they opened a file.

So it would probably need to be a new command, with a new binding, that then does the above behavior.

That's my thoughts at least!

[ChrisMcD1]

Also check out #4263 for some more thoughts about adding additional functionality to that screen (the nested commits inside of the branch view) in particular

[stefanhaller]

This would have to be a new command, the current behavior is the desired one. This was discussed several times before, e.g. here and here.

As mentioned in one of the linked issues, it's relatively easy to approximate the behavior using a custom command, and personally I consider this a satisfactory solution and would be in favor of not adding a bespoke lazygit command for it.

but I'm not aware of an easy way to open that file without also checking out that commit as a detached head

It's easy to cat the file at the given commit hash into a temp file using git show hash:path. The challenge is to decide when to remove the file, since we can't tell when the user is done looking at it.

Finally, a word about o vs. e: the o command is for opening a file in the same way as if you would double-click it in the Finder (or Explorer). This is meant mainly for opening non-text resources such as images or pdfs. If it works for you for opening text files, great, but the e command is meant specifically for opening text files, and it has the advantage that it can jump to the right line in the file when used from the staging view.

[Dagur]

For my purposes it would be enough to add this to the Copy to clipboard... menu. I can paste the content to an editor myself.

[stefanhaller]

@Dagur That's an interesting suggestion, here's a PR that does this: #4341.

[Dagur]

Thank you very much!