So I've only done a couple PRs and am doing my first one that requires generating patches. I screwed up my repository on my first attempt and so am trying to start again fresh, and proceeding more cautiously.

 

So I did the following -- I downloaded latest Forge MDK and ran the setupForge and sucessfully imported the Clean and Forge projects. 

 

I created a branch and did only two very simple changes. 1) added a single test mod file, 2) modified the Material class in the Forge project. 

 

Before I generated the patches I made a commit. Interestingly the git showed that two files changed -- the added test file as expected, but also a jsons/1.12.1.json.  I looked in the file and the changes seemed to be related to the sizes for a couple assets entries. I'm certain I didn't touch these files myself. Why did they show as being changed? Should I commit it or have it in gitignore?

 

But the bigger issue is then I did a genPatches. That completed successfully but now git shows that in addition to the expected patch to Material there is also patches to unrelated stuff, specificaly EntityList and Item classes. The changes are simply the diff annotations. For example it will say something like:

- @@ -435,11 +445,704 @@
+ @@ -435,11 +441,704 @@

 

Why the heck is genPatches creating patches for EntityList and Item that differ when I haven't touched either class?

Leave changes to the json files, they happen due to Mojang tweaking libraries/assets.

 

As for existing patches changing, it's because those files were previously changed without the patches being regenerated properly.

As a result, running genPatches creates patch files that differ from the originals.

 

Just commit the files/patches that correspond to what you've changed.

1 hour ago, quadraxis said:

Leave changes to the json files, they happen due to Mojang tweaking libraries/assets.

 

As for existing patches changing, it's because those files were previously changed without the patches being regenerated properly.

As a result, running genPatches creates patch files that differ from the originals.

 

Just commit the files/patches that correspond to what you've changed.

Okay, cool, that's what I figured for each case.

See this comment:

https://github.com/MinecraftForge/MinecraftForge/pull/4549#discussion_r153260543

1 hour ago, Draco18s said:

See this comment:

https://github.com/MinecraftForge/MinecraftForge/pull/4549#discussion_r153260543

Yeah, that's exactly the sort of thing I've been worrying about. And like you mention there you need habits to keep a pristine copy available to ensure selective changes only make it to your commits.