How to diff one file to an arbitrary version in Git?

Question

How can I diff a file, say pom.xml, from the master branch to an arbitrary older version in Git?

Answer 1

You can do:

git diff master~20:pom.xml pom.xml

... to compare your current pom.xml to the one from master 20 revisions ago through the first parent. You can replace master~20, of course, with the object name (SHA1sum) of a commit or any of the many other ways of specifying a revision.

Note that this is actually comparing the old pom.xml to the version in your working tree, not the version committed in master. If you want that, then you can do the following instead:

git diff master~20:pom.xml master:pom.xml

Answer 2

git diff <revision> <path>

For example:

git diff b0d14a4 foobar.txt

Answer 3

If you want to see the difference between the last commit of a single file you can do:

git log -p -1 filename

This will give you the diff of the file in git, is not comparing your local file.

Answer 4

To see what was changed in a file in the last commit:

git diff HEAD~1 path/to/file

You can change the number (~1) to the n-th commit which you want to diff with.

Answer 5

Generic Syntax :

$git diff oldCommit..newCommit -- **FileName.xml > ~/diff.txt

for all files named "FileName.xml" anywhere in your repo.

Notice the space between "--" and "**"

Answer for your question:

$git checkout master
$git diff oldCommit..HEAD -- **pom.xml 
or
$git diff oldCommit..HEAD -- relative/path/to/pom.xml 

as always with git, you can use a tag/sha1/"HEAD^" to id a commit.

Tested with git 1.9.1 on Ubuntu.

Answer 6

For comparing to 5 commit to the current one, both on master, just simply do:

git diff master~5:pom.xml master:pom.xml

Also you can refer to commit hash number, for example if the hash number is x110bd64, you can do something like this to see the difference:

git diff x110bd64 pom.xml

Answer 7

If neither commit is your HEAD then bash's brace expansion proves really useful, especially if your filenames are long, the example above:

git diff master~20:pom.xml master:pom.xml

Would become

git diff {master~20,master}:pom.xml

More on Brace expansion with bash.

Answer 8

git diff -w HEAD origin/master path/to/file

Answer 9

git diff master~20 -- pom.xml

Works if you are not in master branch too.

Answer 10

If you are fine using a graphical tool (or even prefer it) you can:

gitk pom.xml

In gitk you can then click any commit (to "select" it) and right click any other commit to select "Diff this -> selected" or "Diff selected -> this" in the popup menu, depending on what order you prefer.

Answer 11

For people interested in doing the same from GitHub, see comparing commits across time.

Answer 12

If you need to diff on a single file in a stash for example you can do

git diff stash@{0} -- path/to/file

Answer 13

If you are looking for the diff on a specific commit and you want to use the github UI instead of the command line (say you want to link it to other folks), you can do:

https://github.com/<org>/<repo>/commit/<commit-sha>/<path-to-file>

For example:

https://github.com/grails/grails-core/commit/02942c5b4d832b856fbc04c186f1d02416895a7e/grails-test-suite-uber/build.gradle

Note the Previous and Next links at the top right that allow you to navigate through all the files in the commit.

This only works for a specific commit though, not for comparing between any two arbitrary versions.