Compare foo.bar from two different branches in MAGIT [duplicate]

Question

This answer shows how to see the differences between a specific file foo.bar in two different branches in git. My question is how to do this within magit?

Remit

You can always issue a git command from the magit status buffer by typing : (e.g.: : diff mybranch master -- myfile.cs) – Bismuthinite

Answer 1

I use magit to complement vc. vc already has this functionality C-u C-x v =

Bopp

Can you write what is the command issued for you with this bind? – Remit

Find out for your self. <kbd>C-h k</kbd> <kbd>C-x esc esc</kbd> – Bopp

Is there a way to add some (un)folding functionality to the resulting buffer? Like similar to the one available in *magit-diff* buffer. – Remit

Answer 2

Just wanted to note that this is now directly possible with magit.

In the Magit status buffer, type d to open up the diff popup.

Then limit the diff to your file of interest with =f and the file name.

Finally, do a diff range r and type in the branch that you want to compare to (one can also type in a specific commit on the same branch, see a similar question).

Circum

or from the file buffer: C-c M-g D r – Bismuthinite

=f does not exist... – Clinker

The shortcut has changed to --, is that also the case for you? – Circum

Answer 3

Building up from @dominik-schrempf answer, it is also (now) possible to select the range of the diff with text selection to go quicker than typing the hashes of the commits.

So a quicker (and more visual) sequence could be :

0. Start from any Magit buffer with a list of commits
   (like any commit log or the recent commits list in the Magit status buffer) :

1. Select the commits using text selection

   1a. Have the cursor on one end of the wanted commits

   1b. Toggle text selection C-SPC (or V if you use evil-mode)

   1c. Move your cursor over to the other end of the wanted commits

2. d to open the diff popup

3. d to open the dwim buffer or r for diff range (They do mostly the same thing in this case, I think)

For the text selection part, it is the set-mark-command function of Emacs.
You can learn more about it by using Emacs' integrated help system:

• C-h f followed set-mark-command, or;
• from the execute-extended-command
  (which should be your second best friend after the help prefix key C-h seen above)
  M-x followed by describe-function followed by set-mark-command.

These two paths are equivalent as every Emacs keybindings is calling a function.

In short, use the help prefix and the execute-extended-command often, especially when starting using Emacs.

Tetrastichous

Could you elaborate on "Select the commits"? In the log, under Recent commits? I always see just the diff for the commit under the pointer. – Vallee

Just added some more precise informations. ^^ Let me know if this answers your questions, and if I have some more modifications that could be helpful. I'm not quite sure how to add more though without getting out of scope of the question, but more in-depth information about the non-magit emacs specifics can be found at (Mastering Emacs)[masteringemacs.org/article/mastering-key-bindings-emacs] and (Ergoemacs)[ergoemacs.org/emacs/emacs_esoteric.html]. Happy Hacking :) – Arrange