Merged/9.0.3

Keep install options in requirements.txt from leaking

Mostly indentation complaints, plus an unused test parameter, fixed.
Leaves one new pylint complaint, which is about a test function naming
issue which affects every test.

The list of install options passed into the setup routine is mutable,
passed by reference, so adding items for "this package" to that list
mutates the options for all subsequent packages.

Isolate the lists before mutating them.

Includes a functional test, which has been confirmed to fail without
this fix.

Fixes #3763
Fixes #4453
Fixes #5089

Fixes to vendoring scripts so they work on Windows

Remove test_basic_install_environment_markers

This test relies on buggy setuptools behaviour (keeping
requirements with environment markers in install_requires,
rather than moving them to extras_require) which has been
fixed in recent setuptools versions.

Document PEP 518 support

Fix the date in the changelog

Merged/9.0.2

Use SecureTransport on macOS

(cherry picked from commit 9c037803)

Add an option to allow disabling build isolation

Move all environment management into BuildEnvironment

Run setup.py develop inside of PEP 518 build environment

Use log level info when ignoring packages due to environment markers

Vendor Update - stdout and stderr of shell should be decoded with system encoding

Add a verbosity attribute to basecommand

Setup build environment before first invocation of setup.py and improve test to actually make check that build requirements are installed upon invocation.