cli/parser but for environment variables. This makes it easier to set,
check, document and set defaults for environment variables in a single
location that can be used for query and documentation generation.

Add `mdimporter` stanza to homebrew cask DSL

download_strategy: unlink the lock file after unlocking it

shims/mac/super/pkg-config: fix macOS <=10.13 compatibility

Fixes #7290.

Revert "ARGV: Deprecate ARGV.build_formula_from_source? and ARGV.build_from_source?"

system_command_spec: Make part of bash error regex optional

completions/zsh: add 'pr-pull' options

ENV: don't help include libxml2 on macOS SDK 10.15.4 and later

Initialize Homebrew.args with CLI::Args instance

utils/gems: prioritise Homebrew's chosen Ruby

If we initialize it with OpenStruct, then methods defined in CLI::Args
cannot be called and they would always return nil leading to bugs

shims/mac/super/pkg-config: pass and use HOMEBREW_SDKROOT

ENV/std: withdraw support for Homebrew supplied *.pc files

ARGV: Deprecate ARGV.build_formula_from_source? and ARGV.build_from_source?

Fixes #5068.

build: bump parser from 2.7.0.5 to 2.7.1.0 in /Library/Homebrew

formula_cellar_checks: skip unless Python libs

This avoids an unusual error message when Python is needed for building
(e.g., code generation) but is not used at runtime.

```
==> brew audit recode --online
Error: 1 problem in 1 formula detected
recode:
  * Packages have been installed for:

    but this formula depends on:
      Python 3.7
```

Bumps [parser](https://github.com/whitequark/parser) from 2.7.0.5 to 2.7.1.0.
- [Release notes](https://github.com/whitequark/parser/releases)
- [Changelog](https://github.com/whitequark/parser/blob/master/CHANGELOG.md)
- [Commits](https://github.com/whitequark/parser/compare/v2.7.0.5...v2.7.1.0

)

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

ENV/super: prioritise Xcode if Xcode is a build req

rubocop.yml: enable non-default checks.

update: make git rebase quiet on Mojave system Git.

Closes https://github.com/Homebrew/brew/pull/7258

rubocops/urls: whitelist cspice.

As explained in https://github.com/Homebrew/brew/pull/7256#issuecomment-607787949

shims/mac/super/xcrun: set DEVELOPER_DIR less often

formula_cellar_checks: check Python site packages