Upgrade CI to GitHub workflow.

.github/workflows/.editorconfig

@@ -0,0 +1,2 @@
+[*.yml]
+indent_size = 2

.github/workflows/checks.yml

@@ -0,0 +1,30 @@
+name: Checks
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+
+jobs:
+  composer-normalize:
+    name: Composer Normalize
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Composer normalize
+        uses: docker://ergebnis/composer-normalize-action
+
+  roave-bc-check:
+    name: Roave BC Check
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Roave BC Check
+        uses: docker://nyholm/roave-bc-check-ga

.github/workflows/ci.yml

@@ -0,0 +1,84 @@
+name: CI
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  latest:
+    name: PHP ${{ matrix.php }} Latest
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        php: ['7.1', '7.2', '7.3', '7.4', '8.0']
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php }}
+          tools: composer
+          coverage: none
+
+      - name: Install dependencies
+        run: composer update --prefer-dist --no-interaction --no-progress
+
+      - name: boot test server
+        run: vendor/bin/http_test_server > /dev/null 2>&1 &
+
+      - name: Execute tests
+        run: composer test
+
+  lowest:
+    name: PHP ${{ matrix.php }} Lowest
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        php: ['7.1', '7.2', '7.3', '7.4']
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php }}
+          tools: composer
+          coverage: none
+
+      - name: Install dependencies
+        run: composer update --prefer-dist --prefer-stable --prefer-lowest --no-interaction --no-progress
+
+      - name: boot test server
+        run: vendor/bin/http_test_server > /dev/null 2>&1 &
+
+      - name: Execute tests
+        run: composer test
+
+  coverage:
+    name: Code Coverage
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: 7.4
+          tools: composer
+          coverage: xdebug
+
+      - name: Install dependencies
+        run: composer update --prefer-dist --no-interaction --no-progress
+
+      - name: boot test server
+        run: vendor/bin/http_test_server > /dev/null 2>&1 &
+
+      - name: Execute tests
+        run: composer test-ci

.github/workflows/static.yml

@@ -0,0 +1,36 @@
+name: Static analysis
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+
+jobs:
+  phpstan:
+    name: PHPStan
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: PHPStan
+        uses: docker://oskarstark/phpstan-ga
+        env:
+          REQUIRE_DEV: true
+        with:
+          args: analyze --no-progress
+
+  php-cs-fixer:
+    name: PHP-CS-Fixer
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: PHP-CS-Fixer
+        uses: docker://oskarstark/php-cs-fixer-ga
+        with:
+          args: --dry-run --diff-format udiff

README.md

@@ -2,7 +2,7 @@
 
 [![Latest Version](https://img.shields.io/github/release/php-http/react-adapter.svg?style=flat-square)](https://github.com/php-http/react-adapter/releases)
 [![Software License](https://img.shields.io/badge/license-MIT-brightgreen.svg?style=flat-square)](LICENSE)
-[![Build Status](https://img.shields.io/travis/php-http/react-adapter.svg?style=flat-square)](https://travis-ci.org/php-http/react-adapter)
+[![Build Status](https://img.shields.io/github/workflow/status/php-http/react-adapter/CI.svg?style=flat-square)](https://github.com/php-http/react-adapter/actions?query=workflow%3ACI)
 [![Code Coverage](https://img.shields.io/scrutinizer/coverage/g/php-http/react-adapter.svg?style=flat-square)](https://scrutinizer-ci.com/g/php-http/react-adapter)
 [![Quality Score](https://img.shields.io/scrutinizer/g/php-http/react-adapter.svg?style=flat-square)](https://scrutinizer-ci.com/g/php-http/react-adapter)
 [![Total Downloads](https://img.shields.io/packagist/dt/php-http/react-adapter.svg?style=flat-square)](https://packagist.org/packages/php-http/react-adapter)

composer.json

@@ -11,7 +11,7 @@
         }
     ],
     "require": {
-        "php": "^7.1",
+        "php": "^7.1|^8.0",
         "php-http/httplug": "^2.0",
         "react/http": "^1.0",
         "react/event-loop": "^1.0",