Rebase Tor Browser legacy onto 115.32.0esr

⤵️ Rebase Legacy

NOTE: All examples in this template reference the rebase from 115.17.0esr to 115.18.0esr

Explanation of Variables
  • $(ESR_VERSION): the Mozilla defined ESR version, used in various places for building tor-browser tags, labels, etc
    • Example: 115.18.0
  • $(ESR_TAG): the Mozilla defined hg (Mercurial) tag associated with $(ESR_VERSION)
    • Example: FIREFOX_115_18_0esr_BUILD1
  • $(ESR_TAG_PREV): the Mozilla defined hg (Mercurial) tag associated with the previous ESR version when rebasing (ie, the ESR version we are rebasing from)
    • Example: FIREFOX_115_17_0esr_BUILD1
  • $(BASE_BROWSER_BRANCH): the full name of the current base-browser branch
    • Example: base-browser-115.18.0esr-13.5-1
  • $(BASE_BROWSER_BRANCH_PREV): the full name of the previous base-browser branch
    • Example: base-browser-115.17.0esr-13.5-1
  • $(TOR_BROWSER_BRANCH): the full name of the current tor-browser branch
    • Example: tor-browser-115.18.0esr-13.5-1
  • $(TOR_BROWSER_BRANCH_PREV): the full name of the previous tor-browser branch
    • Example: tor-browser-115.17.0esr-13.5-1

Bookkeeping

Update Branch Protection Rules

  • In Repository Settings:
    • Remove previous legacy base-browser and tor-browser branch protection rules (this will prevent pushing new changes to the branches being rebased)
    • Create new tor-browser branch protection rule:
      • Branch: tor-browser-$(ESR_VERSION)esr-13.5-1*
        • Example: tor-browser-115.18.0esr-13.5-1*
      • Allowed to merge: Maintainers
      • Allowed to push and merge: Maintainers
      • Allowed to force push: false

Identify the Firefox Tagged Commit and Create New Branches

  • Fetch Mozilla's firefox repo and identify this release's ESR-115 ${ESR_TAG}
  • Create new legacy tor-browser branch from
    • Branch name in the form: tor-browser-$(ESR_VERSION)esr-13.5-1
    • Example: tor-browser-115.18.0esr-13.5-1
  • Push new tor-browser branch to upstream
  • Push new $(ESR_TAG) to upstream

Rebase tor-browser

  • Checkout a new local branch for the tor-browser rebase
    • Example: git branch tor-browser-rebase FIREFOX_115_18_0esr_BUILD1
  • tor-browser rebase
    • Note the current git hash of HEAD for tor-browser rebase+autosquash step: git rev-parse HEAD
    • Cherry-pick the appropriate previous tor-browser branch's commit range up to the last tor-browser build1 tag
      • Example: git cherry-pick FIREFOX_115_17_0esr_BUILD1..tor-browser-115.17.0esr-13.5-1-build2
    • Rebase and autosquash these newly cherry-picked commits: git rebase --autosquash --interactive $(PREV_HEAD)
      • Example: git rebase --autosquash --interactive FIREFOX_115_18_0esr_BUILD1
    • Cherry-pick remainder of patches after the last tor-browser build1 tag
      • Example: git cherry-pick tor-browser-115.17.0esr-13.5-1-build1..upstream/tor-browser-115.17.0esr-13.5-1
    • Rebase and pick new security backport patches to the end of the MOZILLA BACKPORTS section of the commit history
      • Example: git rebase --interactive FIREFOX_115_18_0esr_BUILD1
    • 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 FIREFOX_115_18_0esr_BUILD1
  • 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 $(ESR_TAG_PREV)..$(BROWSER_BRANCH_PREV) > current_patchset.diff
      • git diff $(ESR_TAG)..$(BROWSER_BRANCH) > 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
    • rangediff: git range-diff $(ESR_TAG_PREV)..$(TOR_BROWSER_BRANCH_PREV) $(ESR_TAG)..HEAD
      • Example: git range-dif FIREFOX_115_17_0esr_BUILD1..upstream/tor-browser-115.17.0esr-13.5-1 FIREFOX_115_18_0esr_BUILD1..HEAD
  • Open MR for the tor-browser rebase
  • Merge

Sign and Tag

  • Sign/Tag HEAD of the merged tor-browser branch:
    • In tor-browser.git, checkout the new legacy tor-browser branch
    • In tor-browser-build.git, run signing script: 
      ./tools/browser/sign-tag.torbrowser legacy build1
    • Push tag to upstream