Change Concept definition to allow for null codes. #251

	# Copyright 2024 Google LLC
	#
	# Licensed under the Apache License, Version 2.0 (the "License");
	# you may not use this file except in compliance with the License.
	# You may obtain a copy of the License at
	#
	# http://www.apache.org/licenses/LICENSE-2.0
	#
	# Unless required by applicable law or agreed to in writing, software
	# distributed under the License is distributed on an "AS IS" BASIS,
	# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	# See the License for the specific language governing permissions and
	# limitations under the License.

	name: go_test
	on: [push, pull_request]
	jobs:

	go_test:
	runs-on: ${{ matrix.os }}
	strategy:
	matrix:
	os: [ubuntu-latest, macOS-latest, windows-latest]
	steps:

	- name: Set up Go 1.22
	uses: actions/setup-go@v5
	with:
	go-version: 1.22
	id: go

	- name: Check out code
	uses: actions/checkout@v4

	- name: Get dependencies
	run: \|
	go mod download
	- name: Build
	run: \|
	go build ./...

	- name: Test
	run: \|
	go test ./...

	go_spec_test_coverage:
	runs-on: ${{ matrix.os }}
	strategy:
	matrix:
	os: [ubuntu-latest]
	steps:

	- name: Set up Go 1.22
	uses: actions/setup-go@v5
	with:
	go-version: 1.22
	id: go

	- name: Check out code
	uses: actions/checkout@v4

	- name: Get dependencies
	run: \|
	go mod download
	- name: Build
	run: \|
	go build ./...

	- name: Spec Test Coverage
	run: \|
	go run tests/spectests/cmd/analyzer/analyzer.go

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