How should I use git diff for long lines?

Question

I\'m running git-diff on a file, but the change is at the end of a long line.

If I use cursor keys to move right, it loses colour-coding—and worse the lines do

Answer 1

When in trouble, I often resort to DiffMerge. Excellent diff tool that has in-line diff highlighting. Also, in the latest versions they added a mode to have an horizontal mode.

I haven't been able to configure git to use it, though. So I do have to muck around to get both versions of the file first.

Answer 2

With full credit to Josh Diehl in a comment to this answer, I nevertheless feel like this ought to be an answer unto itself, so adding it:

One way to deal with seeing differences in long lines is to use a word-oriented diff. This can be done with:

git diff --word-diff

In this case, you'll get a significantly different diff output, that shows you specifically what has changed within a line.

For example, instead of getting something like this:

diff --git a/test-file.txt b/test-file.txt
index 19e6adf..eb6bb81 100644
--- a/test-file.txt
+++ b/test-file.txt
@@ -1 +1 @@
-this is a short line
+this is a slightly longer line

You might get something like this:

diff --git a/test-file.txt b/test-file.txt
index 19e6adf..eb6bb81 100644
--- a/test-file.txt
+++ b/test-file.txt
@@ -1 +1 @@
this is a [-short-]{+slightly longer+} line

Or, with colorization, instead of this:

You might get this:

Now, if you're comparing a really long line, you may still have issues with the pager situation you originally described, and which has been addressed, apparently to satisfaction, in other answers. Hopefully this gives you a new tool, though, to more easily identify what on the line has changed.

Answer 3

You could simply pipe the output of git diff to more:

git diff | more

Answer 4

Mac OSX: None of the other answers except someone45's '-S' while less is running worked for me. It took the following to make word-wrap persistent:

git config --global core.pager 'less -+$LESS -FRX'

Answer 5

Or if you use less as default pager just type -S while viewing the diff to reenable wrapping in less.

Answer 6

You can also use git config to setup pager to wrap.

$ git config core.pager 'less -r' 

Sets the pager setting for the current project.

$ git config --global core.pager 'less -r' 

Sets the pager globally for all projects