- Make all `odeprecated` from 2.1.0 `odisabled` instead
- Remove dead code that won't be run now
- Remove (unused) `or_later` handling for bottles

Fix some tests

formula: refactor outdated_kegs logic.

upgrade: tweak dependent messaging.

- Use the `Formula.cache` and `Cacheable` rather than rolling our own.
- Use keyword arguments instead of `options = {}`
- Improve readability in general

deps: refactor weird OpenStruct usage.

Output more without requiring `--verbose` and update the messages to
make clear what we're looking for and what we found/didn't find.

This is a little more noisy but it should help explain any delays to
users and make it more obvious what's failed if something does.

build: bump activesupport from 5.2.3 to 6.0.1 in /Library/Homebrew

Improve upgrade dependents check performance, reliability and readability

Dockerfile: make the prefix group writable

build: bump tins from 1.21.1 to 1.22.0 in /Library/Homebrew

Bumps [activesupport](https://github.com/rails/rails) from 5.2.3 to 6.0.1.
- [Release notes](https://github.com/rails/rails/releases)
- [Changelog](https://github.com/rails/rails/blob/v6.0.1/activesupport/CHANGELOG.md)
- [Commits](https://github.com/rails/rails/compare/v5.2.3...v6.0.1

)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

cmd/upgrade: comment-out broken_dependents functionality.

This is not a fix for https://github.com/Homebrew/brew/issues/6671 but
will stop people hitting this bug for now.

bin/brew: unset functions that override builtins

Linux Maintainer Guide: Reflect recent changes to tap commands

- We recently changed the name of the Linux commands tap from
  Linuxbrew/homebrew-developer to Homebrew/homebrew-linux-dev in our
  continual efforts to move away from the Linuxbrew name. Related to
  this, we changed the comment produced by `brew build-bottle-pr` to
  simply "Linux".
- We also [changed `brew
  find-formulae-to-bottle`](https://github.com/Homebrew/homebrew-linux-dev/pull/130)
  so that it will build a bottle for a formula even if it has a macOS
  requirement. There were cases like `go` that build perfectly fine on
  Linux.

Also, enable all Bash builtins

Ruby 2.6 frozen string literals

Now that we use Ruby 2.6 we can fix these last two files.

audit: improve check for forked Bitbucket repository

rubocops: add go@1.12 to BINARY_FORMULA_URLS_WHITELIST