7

For example, let's say I have two files, A and B. I created B as a copy of A but I want them to be very similar - I only want a couple lines different in B. Is there a way in Git to sync these changes in any way, or a more efficient way to accomplish this task?

rb612
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  • Perhaps you could clarify your question a bit. It is unclear to me what you are trying to accomplish. Perhaps a quick example would clear things up. – davethebrave Nov 25 '15 at 07:28
  • I'd rather consider a different design, for it looks to me that you suffer from duplication of code. Unfortunately, there exists no tool that is able to help in dealing with a poor design. – skypjack Nov 25 '15 at 07:28
  • yeah, I was thinking this was a design issue. But let's say I have a method in both files with most of the code the same. However, I make changes in one file that I want to change in the other file. – rb612 Nov 25 '15 at 07:31
  • @rb612 this is a bit off-topic and I don't know what language you are using, but consider something like the template method pattern to deal with such a problem. – skypjack Nov 25 '15 at 07:37

3 Answers3

3

You have the following options:

  1. Use apply-patch-to-file. Where you can generate the patch using:

    git format-patch HEAD^

And then apply using:

apply-patch-to-file -i ~/patches/0001-my-test-commit.patch

You will be prompted and asked on what files the patch should be applied.

  1. Use directly the patch command, by creating the diff like:

    git diff HEAD^ -- hello.test > ~/patch_file

Then apply the diff to a different file:

patch -p1 another_path/subdir/different_file.test ~/patch_file
dan
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0

You can store the diff changes in a file and patch A and B individually using this patch file.

Prasanna
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0

If you can generate that difference, then you could:

  • version A
  • don't version B at all (and add it to your .gitignore actually)
  • add a smudge script which, when reading A content git checkout would generate B.

This is called a content filter driver, using a .gitattributes declaration.

filter

(image from "Customizing Git - Git Attributes", from "Pro Git book")

Community
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VonC
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