Getting the difference between two repositories

Question

How can we get the difference between two git repositories?

The scenario: We have a repo_a and repo_b. The latter was created as a copy of repo_a. There have been pa

Answer 1

Reminder to self... fetch first, else the repository has not local hash (I guess).

step 1. Setup the upstream remote and above^

diffing a single file follows this pattern :

git diff localBranch uptreamBranch --spacepath/singlefile

git diff master upstream/nameofrepo -- src/index.js