fix：修复json字段写入字符串null的bug #480

	name: codecov

	on: [push, pull_request]

	jobs:
	phpunit:
	runs-on: ubuntu-latest
	services:
	mysql:
	image: mysql:5.7
	env:
	MYSQL_ROOT_PASSWORD: password
	MYSQL_DATABASE: testing
	ports:
	- 3306:3306
	options: --health-cmd="mysqladmin ping" --health-interval=10s --health-timeout=5s --health-retries=3

	steps:
	- name: Checkout
	uses: actions/checkout@v1

	- name: Setup PHP
	uses: shivammathur/setup-php@v2
	with:
	php-version: 8.0
	extensions: pdo, pdo_mysql, mbstring #optional, setup extensions
	coverage: xdebug #optional, setup coverage driver

	- name: Check Version
	run: \|
	php -v
	php -m
	composer -V

	- name: Validate composer.json and composer.lock
	run: composer validate

	- name: Get composer cache directory
	id: composercache
	run: echo "::set-output name=dir::$(composer config cache-files-dir)"

	- name: Cache vendor
	uses: actions/cache@v2
	env:
	cache-name: composer-cache
	with:
	path: ${{ steps.composercache.outputs.dir }}
	key: ${{ runner.os }}-build-${{ env.cache-name }}

	- name: Install dependencies (composer.lock)
	run: composer install --prefer-dist --no-progress --no-suggest

	- name: Run test suite
	run: composer exec -- phpunit --coverage-clover=coverage.xml -v
	env:
	TESTS_DB_MYSQL_HOST: 127.0.0.1
	TESTS_DB_MYSQL_PORT: 3306
	TESTS_DB_MYSQL_USERNAME: root
	TESTS_DB_MYSQL_PASSWORD: password
	TESTS_DB_MYSQL_DATABASE: testing

	- name: Codecov
	uses: codecov/codecov-action@v1
	with:
	token: ${{ secrets.CODECOV_TOKEN }} #required
	file: ./coverage.xml #optional
	flags: unittests #optional
	name: codecov-umbrella #optional

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