Rebase Mullvad Browser Stable onto 115.14.0esr

NOTE: All examples in this template reference the rebase from 102.7.0esr to 102.8.0esr

NOTE: It is assumed that we've already rebased and tagged base-browser stable

Bookkeeping

• Link this issue to the appropriate Release Prep issue.

Update Branch Protection Rules

• In Repository Settings:
  • Remove previous stable mullvad-browser branch protection rules (this will prevent pushing new changes to the branches being rebased)
  • Create new mullvad-browser branch protection rule:
    • Branch: mullvad-browser-$(ESR_VERSION)esr-$(BROWSER_MAJOR).$(BROWSER_MINOR)-1*
      • Example: mullvad-browser-102.8.0esr-12.0-1*
    • Allowed to merge: Maintainers
    • Allowed to push and merge: Maintainers
    • Allowed to force push: false

Create and Push New Branch

• Create new stable mullvad-browser branch from this ESR's stable base-browser tag
  • Branch name in the form: mullvad-browser-$(ESR_VERSION)esr-$(BROWSER_MAJOR).$(BROWSER_MINOR)-1
  • Example: git branch mullvad-browser-102.8.0esr-12.0-1 base-browser-102.8.0esr-12.0-1-build1
• Push new mullvad-browser branch to upstream
• Push base-browser tag to upstream
• Push $(ESR_TAG) to upstream

Rebase mullvad-browser

• Checkout a new local branch for the mullvad-browser rebase
  • Example: git branch mullvad-browser-rebase upstream/mullvad-browser-102.8.0esr-12.0-1
• mullvad-browser rebase
  • Cherry-pick the previous mullvad-browser branch's commit range up to the last mullvad-browser build1 tag
    • Example: git cherry-pick base-browser-102.7.0esr-12.0-1-build1..mullvad-browser-102.7.0esr-12.0-1-build1
  • Rebase and autosquash these newly cherry-picked commits
    • Example: git rebase --autosquash --interactive upstream/mullvad-browser-102.8.0esr-12.0-1
  • Cherry-pick remainder of patches after the last mullvad-browser buildN tag
    • Example: git cherry-pick mullvad-browser-102.7.0esr-12.0-1-build1..upstream/mullvad-browser-102.7.0esr-12.0-1
  • Rebase and autosquash again, this time replacing all fixup and squash commands with pick. The goal here is to have all of the fixup and squash commits beside the commit which they modify, but kept un-squashed for easy debugging/bisecting.
    • Example: git rebase --autosquash --interactive upstream/mullvad-browser-102.8.0esr-12.0-1
• Compare patch sets to ensure nothing weird happened during conflict resolution:
  • diff of diffs:
    • Do the diff between current_patchset.diff and rebased_patchset.diff with your preferred difftool and look at differences on lines that starts with + or -
    • git diff $(BASE_BROWSER_BRANCH_PREV_TAG)..$(MULLVAD_BROWSER_BRANCH_PREV) > current_patchset.diff
    • git diff $(BASE_BROWSER_BRANCH_TAG)..HEAD > rebased_patchset.diff
    • diff current_patchset.diff and rebased_patchset.diff
      • If everything went correctly, the only lines which should differ should be the lines starting with index abc123...def456 (unless the previous base-browser branch includes changes not included in the previous mullvad-browser branch)
  • rangediff: git range-diff $(BASE_BROWSER_BRANCH_PREV_TAG)..$(MULLVAD_BROWSER_BRANCH_PREV) $(BASE_BROWSER_BRANCH_TAG)..HEAD
    • Example: git range-diff base-browser-102.7.0esr-12.0-1-build1..upstream/mullvad-browser-102.7.0esr-12.5-1 base-browser-102.8.0esr-12.5-1-build1..HEAD
• Open MR for the mullvad-browser rebase
• Merge

Sign and Tag

• Sign/Tag HEAD of the merged mullvad-browser branch:
  • Tag: mullvad-browser-$(ESR_VERSION)esr-$(BROWSER_MAJOR).$(BROWSER_MINOR)-1-build1
  • Message: Tagging build1 for $(ESR_VERSION)esr-based stable
  • Push tag to upstream