Some chapter 20 Part II coalescing tests #20

	# Make sure autogenerated files are up to date

	name: Check autogenerated files

	on:
	pull_request:
	branches: [ "main" ]

	jobs:

	autogen-files:
	runs-on: ubuntu-latest
	steps:

	# checkout the test suite
	- uses: actions/checkout@v4

	# regenerate autogenerated files
	- name: Generate files
	run: \|
	./generate_expected_results.py
	./gen_from_templates.py

	# make sure those files were already up-to-date
	# (i.e. no untracked changes)
	- name: Check for changes
	run: \|
	git diff --exit-code

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