Here is the scenario
I made some changes and commit the file
I accidentally undo the change in my editor then made some more changes and commit
Now I realized the first change has been rollback.
Here is what I did
Find the finger print of my first change a6dfb30, and find the original finger print 7c54b25, use the following command to generate the patch file
git diff 7c54b25 a6dfb30 -- src/app/dashboard/dashboard.component.html > 1.patch # Then apply the patch git apply 1.patch