pggls: fix FD model in case of group with only one observation #414

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

	name: R-CMD-check

	jobs:
	R-CMD-check:
	runs-on: ${{ matrix.config.os }}

	name: ${{ matrix.config.os }} (${{ matrix.config.r }})

	strategy:
	fail-fast: false
	matrix:
	config:
	- {os: macOS-latest, r: 'release'}
	- {os: windows-latest, r: 'release'}
	- {os: ubuntu-latest, r: 'devel', http-user-agent: 'release'}
	# - {os: ubuntu-latest, r: 'release'}
	# - {os: ubuntu-latest, r: 'oldrel-1'}

	env:
	GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}
	R_KEEP_PKG_SOURCE: yes

	steps:
	- uses: actions/checkout@v3

	- uses: r-lib/actions/setup-pandoc@v2

	- uses: r-lib/actions/setup-r@v2
	with:
	r-version: ${{ matrix.config.r }}
	http-user-agent: ${{ matrix.config.http-user-agent }}
	use-public-rspm: true

	- uses: r-lib/actions/setup-r-dependencies@v2
	with:
	extra-packages: rcmdcheck

	- uses: r-lib/actions/check-r-package@v2
	with:
	args: 'c("--no-manual", "--as-cran", "--test-dir=inst/tests")'

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

	- name: Upload check results
	if: failure()
	uses: actions/upload-artifact@main
	with:
	name: ${{ runner.os }}-r${{ matrix.config.r }}-results
	path: check

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