ci: configure GitHub Actions

.editorconfig

@@ -7,3 +7,11 @@ indent_size = 4
 end_of_line = lf
 insert_final_newline = true
 trim_trailing_whitespace = true
+
+[*.yaml]
+charset = utf-8
+indent_style = space
+indent_size = 2
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true

.github/workflows/php7-3.yaml

@@ -0,0 +1,34 @@
+name: "[PHP 7.3] Run tests"
+
+on:
+  - push
+  - pull_request
+
+jobs:
+  tests:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: "7.3"
+          tools: composer
+
+      - name: Validate composer.json and composer.lock
+        run: composer validate
+
+      - name: Install dependencies
+        run: composer install --prefer-dist
+
+      - name: Run tests
+        run: ./vendor/bin/phpunit
+
+      - name: Coveralls
+        run: ./vendor/bin/php-coveralls -v
+        env:
+          COVERALLS_RUN_LOCALLY: 1
+          COVERALLS_REPO_TOKEN: ${{ secrets.COVERALLS_REPO_TOKEN }}

.github/workflows/php7-4.yaml

@@ -0,0 +1,28 @@
+name: "[PHP 7.4] Run tests"
+
+on:
+  - push
+  - pull_request
+
+jobs:
+  tests:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: "7.4"
+          tools: composer
+
+      - name: Validate composer.json and composer.lock
+        run: composer validate
+
+      - name: Install dependencies
+        run: composer install --prefer-dist
+
+      - name: Run tests
+        run: ./vendor/bin/phpunit

.github/workflows/php8-0.yaml

@@ -0,0 +1,28 @@
+name: "[PHP 8.0] Run tests"
+
+on:
+  - push
+  - pull_request
+
+jobs:
+  tests:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: "8.0"
+          tools: composer
+
+      - name: Validate composer.json and composer.lock
+        run: composer validate
+
+      - name: Install dependencies
+        run: composer install --prefer-dist
+
+      - name: Run tests
+        run: ./vendor/bin/phpunit