test: add test case `mutable::range` & `merge_stream::merge_mutable_r… #20

	name: CI

	on:
	push:
	pull_request:

	env:
	CARGO_TERM_COLOR: always
	CARGO_REGISTRIES_MY_REGISTRY_INDEX: https://github.com/rust-lang/crates.io-index

	jobs:
	# 1
	check:
	name: Rust project check
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- name: Install latest
	uses: actions-rs/toolchain@v1
	with:
	toolchain: stable
	override: true
	components: rustfmt, clippy

	- name: Install Protoc
	uses: arduino/setup-protoc@v2

	# `cargo check` command here will use installed `nightly`
	# as it is set as an "override" for current directory

	- name: Run cargo check
	uses: actions-rs/cargo@v1
	with:
	command: check

	- name: Run cargo build
	uses: actions-rs/cargo@v1
	with:
	command: build

	- name: Run cargo test
	uses: actions-rs/cargo@v1
	with:
	command: test
	# 2
	fmt:
	name: Rust fmt
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- name: Install latest nightly
	uses: actions-rs/toolchain@v1
	with:
	toolchain: nightly
	override: true
	components: rustfmt, clippy

	# `cargo check` command here will use installed `nightly`
	# as it is set as an "override" for current directory

	- name: Run cargo fmt
	uses: actions-rs/cargo@v1
	with:
	command: fmt
	args: -- --check

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