Improve Handling of `cpp_options` #1980

	---
	# Github Actions workflow to analyze CmdStanR code, test coverage
	# yamllint disable rule:line-length

	name: Test coverage

	'on':
	push:
	branches:
	- master
	pull_request:
	branches:
	- master

	jobs:
	test-coverage:
	if: "! contains(github.event.head_commit.message, '[ci skip]')"
	runs-on: ${{ matrix.config.os }}

	name: ${{ matrix.config.os }}

	strategy:
	fail-fast: false
	matrix:
	config:
	- { os: windows-latest }
	- { os: ubuntu-latest }
	env:
	GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}
	NOT_CRAN: true

	steps:
	- name: cmdstan env vars
	run: \|
	echo "CMDSTAN_PATH=${HOME}/.cmdstan" >> $GITHUB_ENV
	shell: bash

	- uses: n1hility/cancel-previous-runs@v3
	with:
	token: ${{ secrets.GITHUB_TOKEN }}
	workflow: Test-coverage.yml
	if: "!startsWith(github.ref, 'refs/tags/') && github.ref != 'refs/heads/master'"
	- uses: actions/checkout@v4

	- uses: r-lib/actions/[email protected]
	- uses: r-lib/actions/[email protected]

	- uses: r-lib/actions/[email protected]
	with:
	extra-packages: any::rcmdcheck, local::., any::covr, any::gridExtra

	- name: Install cmdstan
	run: \|
	cmdstanr::check_cmdstan_toolchain(fix = TRUE)
	cmdstanr::install_cmdstan(cores = 2)
	shell: Rscript {0}

	- name: Test coverage (Linux)
	if: runner.os == 'Linux'
	run: covr::codecov(type = "tests")
	shell: Rscript {0}

	- name: Test coverage (Windows)
	if: runner.os == 'Windows'
	run: \|
	options(covr.gcov = 'C:/rtools44/mingw64/bin/gcov.exe');
	covr::codecov(type = "tests", function_exclusions = "sample_mpi")
	shell: Rscript {0}

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