command line - Using 'diff' (or anything else) to get character-level diff between text files

Question

I'd like to use 'diff' to get a both line difference between and character difference. For example, consider:

File 1

abcde
abc
abcccd

File 2

abcde
ab
abccc

Using diff -u I get:

@@ -1,3 +1,3 @@
 abcde
-abc
-abcccd
 No newline at end of file
+ab
+abccc
 No newline at end of file

However, it only shows me that were changes in these lines. What I'd like to see is something like:

@@ -1,3 +1,3 @@
 abcde
-ab<ins>c</ins>
-abccc<ins>d</ins>
 No newline at end of file
+ab
+abccc
 No newline at end of file

You get my drift.

Now, I know I can use other engines to mark/check the difference on a specific line. But I'd rather use one tool that does all of it.

Answer 1

Git has a word diff, and defining all characters as words effectively gives you a character diff. However, newline changes are ignored.

Example

Create a repository like this:

mkdir chardifftest
cd chardifftest
git init
echo -e 'foobarbaz
catdog
fox' > file
git add -A; git commit -m 1
echo -e 'fuobArbas
cat
dogfox' > file
git add -A; git commit -m 2

Now, do git diff --word-diff=color --word-diff-regex=. master^ master and you'll get:

Note how both additions and deletions are recognized at the character level, while both additions and deletions of newlines are ignored.

You may also want to try one of these:

git diff --word-diff=plain --word-diff-regex=. master^ master
git diff --word-diff=porcelain --word-diff-regex=. master^ master