Use internal mutability for `SharedMemoryLimiter`, removing one `RefCell`. #195

	name: CI

	on:
	pull_request:
	push:
	branches:
	- master

	env:
	RUSTFLAGS: -Dwarnings
	RUST_BACKTRACE: 1

	jobs:
	clippy:
	name: clippy
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	with:
	submodules: 'recursive'
	- name: Install Rust
	run: rustup update stable && rustup default stable
	- name: Get rust version
	id: rust-version
	run: echo "::set-output name=version::$(rustc --version)"
	- name: Cache cargo index and registry
	uses: actions/cache@v1
	with:
	key: immutable # this will always be hit because it's a constant
	path: \|
	~/.cargo/registry/cache
	~/.cargo/registry/index
	- name: Create lockfile
	run: cargo generate-lockfile
	- name: Fetch dependencies
	run: cargo fetch
	- name: Cache target directory
	uses: actions/cache@v1
	with:
	path: target
	key: clippy-target-${{ runner.os }}-${{ steps.rust-version.outputs.version }}-${{ hashFiles('Cargo.lock') }}
	- name: Run clippy
	run: cargo clippy --all --all-targets
	test:
	name: Test
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- name: Install Rust (rustup)
	run: rustup update stable --no-self-update && rustup default stable
	shell: bash
	- name: Run tests
	run: scripts/test.sh
	format:
	name: Check code format
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- name: Install Rust (rustup)
	run: \|
	rustup update stable --no-self-update && rustup default stable
	rustup component add rustfmt
	shell: bash
	- name: Check format
	run: cargo fmt -- --check

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