How to diff PDF files with Git

how-to-diff-pdf-files-with-git-and-diffpdf.md

One can use MD5 or plain text diff to see differences in PDF files. If that's not enough, here's how to use diff-pdf which knows how to diff based on appearance or words:

• brew install diff-pdf
• edit your ~/.gitconfig to add this:

[difftool "diffpdf"]
  cmd = diff-pdf --view \"$LOCAL\" \"$REMOTE\"

• then use with:

git difftool --tool=diffpdf your_pdf_file.pdf

I suspect there's maybe some way to force always using a specific difftool for files with a specific extension; in the mean time I'm just using a bash function for this.

Also useful in .bash_profile:

function git_diff_pdf {
  yes | git difftool --tool=diffpdf $1
}

then you can use it like:

git_diff_pdf your_pdf_file.pdf

With a recent version of git (I'm using 2.40.1) you can do this pretty easily using diff in both the git config and .gitattributes (official docs):

In your project's .gitattributes:

*.pdf diff=diff-pdf

In your ~/.gitconfig or your project's .git/config:

[diff "diff-pdf"]
        command = f() { diff-pdf --view "$2 $1;" } ";" f