Pants ci: Run self-check tests w/ venv generated by pants #1817

	---
	name: Validate Pants Metadata

	on:
	push:
	branches:
	# only on merges to master branch
	- master
	# and version branches, which only include minor versions (eg: v3.4)
	- v[0-9]+.[0-9]+
	tags:
	# also version tags, which include bugfix releases (eg: v3.4.0)
	- v[0-9]+.[0-9]+.[0-9]+
	pull_request:
	type: [opened, reopened, edited]
	branches:
	# Only for PRs targeting those branches
	- master
	- v[0-9]+.[0-9]+

	jobs:
	pants-tailor:
	name: Make sure pants BUILD files are up-to-date
	runs-on: ubuntu-20.04
	steps:
	- name: Checkout repository
	uses: actions/checkout@v4
	with:
	# a test uses a submodule, and pants needs access to it to calculate deps.
	submodules: 'true'

	- name: Initialize Pants and its GHA caches
	uses: ./.github/actions/init-pants
	with:
	# To ignore a bad cache, bump the cache* integer.
	gha-cache-key: cache0-BUILD

	- name: Check BUILD files
	run: \|
	pants tailor --check update-build-files --check ::

	- name: Upload pants log
	uses: actions/upload-artifact@v4
	with:
	name: pants-log-py${{ matrix.python-version }}
	path: .pants.d/pants.log
	if: always() # We want the log even on failures.

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