A full and verbose description of how to create patches and interdiffs for submission to the Drupal issue queue.

drupal-patch-strategy.md

Drupal Patch Strategy:

Patches

1. make changes then make patch BEFORE COMMITTING CHANGES

• $ git diff > [project-name]-[project-version].[description].[issue-number]-[comment-number].patch
• doesn't work when adding or deleting files

2. you've made changes that INCLUDE adding/deleting files, BUT NOT COMMITTED

• $ git [add|rm] ...
• $ git diff --staged > [project-name]-[project-version].[description].[issue-number]-[comment-number].patch

3. you've made your changes AND YOU'VE COMMITTED the new changes AND there's ONLY BEEN ONE COMMIT (from base state to new state)

• get the commit-hash if you don't have it already
  • $ echo $(git log --format=%H -n1)
• $ git show COMMIT_HASH > [project-name]-[project-version].[description].[issue-number]-[comment-number].patch

4. you need to create a patch between two specific commits in the same branch (because you've made many commits between the base state and end state)

• get the commit-hashes you're comparing
• $ git show OLD_COMMIT_HASH..NEW_COMMIT_HASH > [project-name]-[project-version].[description].[issue-number]-[comment-number].patch

5. if you've made your changes to a branch; i.e. you've cloned, checked out the branch/tag that needs to be patched and then created a branch based off the HEAD of that branch

• $ git diff ORG_BRANCH_NAME > [project-name]-[project-version].[description].[issue-number]-[comment-number].patch

Interdiff

1. checkout the branch that needs patching (and has a pre-existing patch) (has an issue logged against it)

• $ git clone GIT_URL --branch 8.x

2. create a new branch based off of the HEAD of the one you checked out

• $ git checkout -b ISSUEID-COMMENTID

3. apply the old patch and commit it

• $ git apply --index old_patch.patch && git commit -m "old patch"

4. create a new branch to make your changes to

• $ git checkout -b new_patch

5. hackity hack
6. commit the changes you've just made as many times as you need to... work until you're satisfied

• $ git commit -m "new patch"

7. generate the new patch file to submit; this will include all the previous changes that were submitted PLUS those you've made too

• $ git diff 8.x > patch.patch

8. generate the interdiff, you'll be running the diff off of the original branch you made in step 2. (BEFORE applying the pre-existing patch)

• $ git diff ISSUEID-COMMENTID > interdiff.txt

Credits: Big, big thanks to @mparker17!!! :o)