Throw classed error if `allow_empty = FALSE` + add more context to error message by adding `error_arg` to `eval_select()` #298

	# Workflow derived from https://github.com/r-lib/actions/tree/v2/examples
	# Need help debugging build failures? Start at https://github.com/r-lib/actions#where-to-find-help
	on:
	push:
	branches: [main, master]
	pull_request:
	branches: [main, master]

	name: test-coverage.yaml

	permissions: read-all

	jobs:
	test-coverage:
	runs-on: ubuntu-latest
	env:
	GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}

	steps:
	- uses: actions/checkout@v4

	- uses: r-lib/actions/setup-r@v2
	with:
	use-public-rspm: true

	- uses: r-lib/actions/setup-r-dependencies@v2
	with:
	extra-packages: any::covr, any::xml2
	needs: coverage

	- name: Test coverage
	run: \|
	cov <- covr::package_coverage(
	quiet = FALSE,
	clean = FALSE,
	install_path = file.path(normalizePath(Sys.getenv("RUNNER_TEMP"), winslash = "/"), "package")
	)
	covr::to_cobertura(cov)
	shell: Rscript {0}

	- uses: codecov/codecov-action@v4
	with:
	fail_ci_if_error: ${{ github.event_name != 'pull_request' && true \|\| false }}
	file: ./cobertura.xml
	plugin: noop
	disable_search: true
	token: ${{ secrets.CODECOV_TOKEN }}

	- name: Show testthat output
	if: always()
	run: \|
	## --------------------------------------------------------------------
	find '${{ runner.temp }}/package' -name 'testthat.Rout*' -exec cat '{}' \; \|\| true
	shell: bash

	- name: Upload test results
	if: failure()
	uses: actions/upload-artifact@v4
	with:
	name: coverage-test-failures
	path: ${{ runner.temp }}/package

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