setting tabwidth to 4 in git show / git diff

Question

At work we are several developers and don't have a code style guide, and some developers indent with tabs, and some others with 4 spaces (luckily noone of the indent with spaces people uses different than 4 spaces). In general this is no (big) problem because in our editors we set tabwidth=4 and all the indentation seems correct.

But in git diff or git show that's what appears:

diff --git a/mesclatabs.php b/mesclatabs.php
new file mode 100644
index 0000000..1986c91
--- /dev/null
+++ b/mesclatabs.php
@@ -0,0 +1,5 @@
+<?php
+function foo() {
+       echo "line with 1 tab\n";
+    echo "line with 4 spaces\n";
+}

The problem is git diff or git show where each tabs appears as wide as 8 spaces (well, in reality appears as a tab, and the shell (bash in my case) is showing the tab as 8 spaces. I suppose there must be some bash config to change this, but I'd like to know if git has an option to output tabs as 4 spaces in diff / show, as some developers work with zsh instead of bash.

Any ideas?

Octad

in an ideal world the devs would all use spaces and you won't have silly issues like this. – Monostrophe

I completely disagree. Why would you represent something with 4 characters when you can represent it with 8? – Intellectualism

Of course I don't know your situation, but I would really push for some super-basic coding guidelines, maybe just about the tabs/spaces. No tabs sounds like a good idea, because then people tend to use tabs to align their comments and such, too, and it becomes a mess... And inserting tabs after spaces... It's confusing when I go to edit and I can't see what's a tab and what's a space (so I always make tabs visible in my editor). I'm a bit neurotic about it, though, so </opinion> – Flabby

Also, I think it's possible to use (only) tabs consistently for indenting code, and spaces for any other alignment, and then people can change the tabstop to whatever they want. I can't imagine people being consistent enough, though! – Flabby

@MatthewG 8 sounds a lot grander than my 2... Thank you for showing me the light! :D – Flabby

Answer 1

I believe git config --global core.pager 'less -x1,5'

References:

• Original: (No longer valid) git-scm chp7-1
• Newer:
  • git-config#git-config-corepager
  • Customizing Git

Schnauzer

The argument to less should be -x5 because the +/- symbols of the unified diff don't impact the location of the tab-stop, but they do push all the spaces one character to the right. A tab-stop of 5 aligns everything properly. – Siege

yes, that works, setting -x5 as CodeGnome said. Thank you both very much – Alyce

urgh, it worked on just the first indentation level, at second, third, ... it does not align because of the initial + in the diffs. I'll leave at -x4 as setting it higher misaligns it one char more for every indentation level (and also on non-added/removed lines is more consistent). – Alyce

how to fix space in git --color=always | less -r ? less -x1,5 is invalid – Termor

@ZhengKai: Just as a data point, I have less aliased as less -R, core.pager defined as above, and I run git diff --color-words -- everything works fine and the tab width is correct. Maybe that helps? – Jericajericho

Doesn't work for me on Ubuntu 14.04 - If I do this then the colouring escape sequences get shown instead of doing the colouring e.g. ESC[1mdiff --git a/.gitignore b/.gitignoreESC[m ESC[1mindex 6f4a9ba..4dc6e8d 100644ESC[m – Lanfranc

When I do git add -p the pager is not used and the tab displayed in wrong way. If you describe how to fix this too. then the answer will be full – Pharyngitis

How to use this with -r, I want both -r and -x1,5, but less -r -x1,5 does not behavior as expected. – Studdingsail

@chenzhiwei: I've used git config --global core.pager 'less -r -x1,4' (3 space indent) and it works perfectly. (Note that GIT apparently sets the LESS=-r environ by default, but that shouldn't cause any issues in this case.) – Regenerate

@Studdingsail - I haven't looked at this in many years from first answering, so I can't speak to the defaults back then. According to the documentation (edited to reference valid links) if LESS is unset Git sets it to FRX, otherwise if LESS is set, Git does not change it. – Schnauzer

@IanRogers - For colour escape sequences you'd want to use less -R / --RAW-CONTROL-CHARS linux.die.net/man/1/less – Schnauzer

For those wondering, in -x1,5 the 1 is for the leading column in the diff output (that contains +, - and a space). Subsequent tabs then jump to columns 5, 9, 13, 17, etc - aka 1 + multiples of 4. So, for git diff the right argument is definitely -x1,5. People claiming above that -x5 works for them ... well - that's a tab width of 5 spaces without a leading column, hmm. Unlikely? – Printer

-x5 didn't work for me in the sense that it seems to have broken ANSI escape sequence processing -- less output started showing a lot of ESC[31m-, ESC[m and other similar sequences. Something to do with the - in the -x5 -- Rx5, -x1,5, Rx4 do not disrupt the ANSI escape sequence processing (regardless of their correctness). Furthermore, even with R-x5, subsequent tab stops are 5 characters apart, which seems to be definitely wrong. – Ernst

Is there a way to make less -x1,5 also work for git combined diffs, which have N leading columns, where N is the number of parent commits? – Henchman

Answer 2

On MacOS you could do

$ git config --global core.pager 'less --tabs 4'

-x/--tabs is the same option I prefer to use full ones. From man less

-xn,... or --tabs=n,...
Sets tab stops. If only one n is specified, tab stops are set at multiples of n. If multiple values separated by commas are speci- fied, tab stops are set at those positions, and then continue with the same spacing as the last two. For example, -x9,17 will set tabs at positions 9, 17, 25, 33, etc. The default for n is 8.

Lower

Answer 3

As the answer https://mcmap.net/q/234034/-setting-tabwidth-to-4-in-git-show-git-diff did not work for me because of my color settings I came up with following solution:

TAB=$'\t' && git config --global core.pager "sed 's/$TAB/    /g' | less" && unset TAB

This replaces all tab characters with 4 spaces before displaying it with less. (The TAB workaround is needed to circumvent the shells backslash escape)

Skylight

I'm not on something I can test with, but would this be where less -R would come into play? to allow the ANSI colour escape sequences through, opposed to less -r? – Schnauzer