For a long time now, I've wished for what has generally seemed to me like a fairly straightforward and obvious Git tool. What I want is a convenient way to page through all of the different versions of a file over time, going 'forward' and 'backward' through them. Basically this would be the whole file version of 'git log -p FILE', although it couldn't have the same interface.

(I know that the history may not be linear. There are various ways to cope with this, depending on how sophisticated an interface you're presenting.)

When I first started wanting this, it felt so obvious that I couldn't believe it didn't already exist. Going through past versions of a file was something that I wanted to do all the time when I was digging through repositories, and I didn't get why no one else had created this. Now, though, I think that my unusual desire for this is one of the signs that I use Git repositories differently from most people, because I'm coming at them as a sysadmin instead of as a developer. Or, to put it another way, I'm reading code as an outsider instead of an insider.

When you're an insider to code, when you work on the code in the repository you're reading, you have enough context to readily understand diffs and so 'git log -p' and similar diff-based formats (such as 'git show' of a commit) are perfectly good for letting you understand what the code did in the past. But I almost never have that familiarity with a Git repo I'm investigating. I barely know the current version of the file, the one I can read in full in the repo; I completely lack the contextual knowledge to mentally apply a diff and read out the previous behavior of the code. To understand the previous behavior of the code, I need to read the full previous code. So I wind up wanting a convenient way to get that previous version of a file and to easily navigate through versions.

(There are a surprising number of circumstances where understanding something about the current version of a piece of code requires me to look at what it used to do.)

I rather suspect that most people using Git are developers instead of people spelunking the depths of unfamiliar codebases. Developers likely don't have much use for viewing full versions of a file over time (or at least it's not a common need), so it's probably not surprising that there doesn't seem to be a tool for this (or at least not an easily found one).

(Github has something that comes close to this, with the 'view blame prior to this change' feature in its blame view of a particular file. But this is not quite the same thing, although it is handy for my sorts of investigations.)