Update parsetree #255

	name: Build on Linux

	# Build and run tests on ubuntu-latest.

	on:
	push:
	branches:
	- main
	- jane
	pull_request:
	workflow_dispatch:

	jobs:
	build-linux:
	strategy:
	fail-fast: false
	matrix:
	ocaml-compiler:
	# Don't include every versions. OCaml-CI already covers that
	- 5.2.x

	runs-on: ubuntu-latest

	steps:
	# Clone the project
	- uses: actions/checkout@v2
	with:
	# Don't checkout the implicit merge commit to avoid wrong substitution
	ref: ${{ github.event.pull_request.head.sha }}

	# Setup
	- name: Setup OCaml ${{ matrix.ocaml-version }}
	uses: ocaml/setup-ocaml@v2
	with:
	ocaml-compiler: ${{ matrix.ocaml-compiler }}

	- name: Opam dependencies
	run: opam install --deps-only -t .

	- name: Self-formatting test
	run: opam exec -- dune build @fmt

	- name: Build
	run: \|
	opam exec -- dune subst
	opam exec -- dune build -p ocamlformat-lib,ocamlformat

	- name: Runtest
	run: opam exec -- dune runtest

	- name: Check manpages
	run: opam exec -- dune build @gen_manpage --auto-promote

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