setting tabwidth to 4 in git show / git diff

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?

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• Original: (No longer valid) git-scm chp7-1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

As the answer https://stackoverflow.com/a/10584237/1850340 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)