manually-pass-two-git-files-to-delta.md

Manually Pass Two Git Files To Delta

I recently wired up delta as my default pager and differ for git. However, when I installed delta, I first wanted to see what its diff output looked like.

How can I pass two versions of the same file from git to delta?

I can show the current contents of a file with git show referencing the HEAD commit.

$ git show HEAD:main.go

Similiarly, I can show the contents of that file one commit ago with HEAD~.

$ git show HEAD~:main.go

I can then pass each of those commands as virtual files to delta using the <() syntax. The older file goes first and the newer second.

$ delta <(git show HEAD~:main.go) <(git show HEAD:main.go)

That works and comes in handy if you need to compare two things that aren't necessarily files or aren't necessarily under version control. However, in hindsight, I'd say it is easier to add delta as the pager and differ and try it out directly.