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Comment by ozay | Hacker News Reader

git blame shows only who made the last change. Maybe that person only changed the name of a variable, applied a codestyle change, moved a function declaration to another file or many other things that the change was almost irrelevant to the code behavior.

There are a few options that help you out with this:

-M Detect moved or copied lines within a file

-C In addition to -M, detect lines moved or copied from other files that were modified in the same commit.

--ignore-rev <rev> Ignore changes made by the revision when assigning blame, as if the change never happened

--ignore-revs-file <file> Ignore revisions listed in file

https://git-scm.com/docs/git-blame

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I wish they would make long option names for everything, including -C and -M. (Perhaps I should contribute that..)

I use short options interactively on the command line, but in scripts and when communicating with other people, I prefer longer options because they are self-documenting and can catch most typos. (For a long option, typos are more likely to result in an invalid option, and thus an error message. For one-letter options, a typo could result in anything..)

FWIW, -C has precedents: `make` and `tar` have the same option with the same meaning.

Yes, sticking to precedent is a good idea in general, too. But that's independent of long options.

I recommend just skipping blame and going to git log -L to see the full evolution of a range of lines, I set up a little keybind in vim which does this for the current visual selection and it works much better than blame.

And for those using Magit in Emacs, you can do this by selecting a region of lines and hitting `C-c M-g l`.

https://magit.vc/manual/magit/Commands-for-Buffers-Visiting-...

There's also git time machine to quickly rollback a buffer in place

This feature is built into Emacs, no Magit needed. It's the vc-region-history command, bound to `C-x v h` by default. It works across all version control systems Emacs supports, not just git.

Nice. Can you share your vim configuration for that?

My config is kind of cluttered so this is a simplified version without dependencies. Glogr is for range history, GLogf for file history and <leader>gc for showing a commit based on hash:

    nnoremap <leader>gc :Gshow <C-R><C-W><cr>
    command! -nargs=1 Gshow enew | set ft=diff buftype=nofile | 0r!git log -p -n 1 "<args>"
    command! -nargs=0 Glogf tabnew | set ft=diff buftype=nofile | 0r!git -C "#:h" log -p --follow "#:t"
    command! -nargs=0 -range Glogr tabnew | set ft=diff buftype=nofile | 0r!git -C "#:h" log -L "<line1>,<line2>:#:t"

These are the things that can be a chore to find in man pages. There needs to be a way to "sort" man page elements to show most commonly used switches first.

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