Make flatten task smarter #2079

	name: Hardhat Network Forking Functionality CI

	on:
	push:
	branches: [$default-branch]
	paths:
	- "packages/hardhat-core/**"
	- "packages/hardhat-common/**"
	- "config/**"
	pull_request:
	branches:
	- "**"
	paths:
	- "packages/hardhat-core/**"
	- "packages/hardhat-common/**"
	- "config/**"

	defaults:
	run:
	working-directory: packages/hardhat-core

	concurrency:
	group: ${{github.workflow}}-${{github.ref}}
	cancel-in-progress: true

	jobs:
	# We should run this tests with multiple configurations
	# but somehow the requests to Alchemy take much longer when doing that.
	# As a temporary workaround, we run them with a single config.
	#
	# Once we properly refactor Hardhat Network's tests we should
	# add more configurations (different OS and node versions).
	#
	# We should also understand what's going on before blindly refactoring them.
	test_fork:
	name: Test Hardhat Network's forking functionality
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- uses: actions/setup-node@v2
	with:
	node-version: 16
	cache: yarn
	- name: Install
	run: yarn --frozen-lockfile
	- name: Cache network requests
	uses: actions/cache@v2
	with:
	path: \|
	packages/hardhat-core/test/internal/hardhat-network/provider/.hardhat_node_test_cache
	key: hardhat-network-forking-tests-${{ hashFiles('yarn.lock') }}-${{ hashFiles('packages/hardhat-core/test/internal/hardhat-network/provider/node.ts') }}
	- name: Run tests
	env:
	INFURA_URL: ${{ secrets.INFURA_URL }}
	ALCHEMY_URL: ${{ secrets.ALCHEMY_URL }}
	DO_NOT_SET_THIS_ENV_VAR____IS_HARDHAT_CI: true
	FORCE_COLOR: 3
	run: \|
	yarn build
	yarn test:forking

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