Add per-mixin workflow for linting #11

	---
	name: Mixin

	permissions:
	contents: read

	on:
	# To conserve resources we only run tests against main in PRs
	pull_request:
	branches:
	- master

	jobs:
	check-for-changed-mixins:
	name: Check for changes
	runs-on: ubuntu-latest
	outputs:
	changed-mixins: ${{ steps.changed-mixins.outputs.all_changed_files }}
	steps:
	- name: Checkout
	uses: actions/checkout@v4
	with:
	fetch-depth: 0

	- name: Setup Go
	uses: actions/setup-go@v5
	with:
	go-version: 1.18

	- name: Install CI dependencies
	run: make install-ci-deps

	- name: Get changed mixins
	id: changed-mixins
	uses: tj-actions/changed-files@v44
	with:
	dir_names: true
	dir_names_exclude_current_dir: true
	dir_names_max_depth: 1
	files: \|
	**-mixin/
	**-observ-lib/
	matrix: true

	- name: List all changed mixins
	run: echo '${{ steps.changed-mixins.outputs.all_changed_files }}'

	lint-mixin:
	name: Run Mixtool
	runs-on: ubuntu-latest
	permissions:
	issues: write
	contents: write
	pull-requests: write
	repository-projects: write
	timeout-minutes: 15
	needs: [check-for-changed-mixins]
	strategy:
	matrix:
	mixin: ${{ fromJSON(needs.check-for-changed-mixins.outputs.changed-mixins) }}
	fail-fast: false
	steps:
	- name: Checkout
	uses: actions/checkout@v4
	with:
	fetch-depth: 0

	- name: Setup Go
	uses: actions/setup-go@v5
	with:
	go-version: 1.18

	- name: Install CI dependencies
	run: make install-ci-deps

	- name: Install Mixin dependencies
	working-directory: ./${{ matrix.mixin }}
	run: jb install

	- name: Lint Mixin
	working-directory: ./${{ matrix.mixin }}
	run: mixtool lint mixin.libsonnet

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