Introduce code tests

.github/workflows/phpcompatibility.yml

@@ -0,0 +1,9 @@
+name: PHPCompatibility
+on: [push]
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+    - name: 7.0-8-0
+      run: docker run --rm -v $PWD:/code domw/phpcompatibility:8.0-cli phpcs --standard=PHPCompatibility --runtime-set testVersion 7.0-8.0 --colors --warning-severity=0 --report=full,summary --extensions=php,phtml ./

.github/workflows/phpcs.yml

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+name: M2 Coding Standard
+on: [push, pull_request]
+
+jobs:
+  static:
+    name: M2 Coding Standard
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: extdn/github-actions-m2/magento-coding-standard@master

.github/workflows/phpcsfixer.yml

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+name: php-cs-fixer
+on: [push]
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+    - name: PHP CS Fixer
+      run: docker run --rm -v $PWD:/code domw/php-cs-fixer php-cs-fixer fix --dry-run --diff --stop-on-violation --allow-risky=yes ./

.github/workflows/phpstan.yml

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+name: M2 PHPStan
+on: [push, pull_request]
+
+jobs:
+  phpstan:
+    name: M2 PHPStan
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: extdn/github-actions-m2/magento-phpstan@master
+        with:
+          composer_name: reviewscouk/reviews

.php-cs-fixer.dist.php

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+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+
+/**
+ * PHP Coding Standards fixer configuration
+ */
+
+$finder = PhpCsFixer\Finder::create()
+    ->in('Block')
+    ->in('Controller')
+    ->in('Helper')
+    ->in('Model')
+    ->in('Observer')
+    ->in('view')
+    ->name('*.phtml');
+
+$config = new PhpCsFixer\Config();
+$config->setFinder($finder)
+    ->setRules([
+        '@PSR2' => true,
+        'array_syntax' => ['syntax' => 'short'],
+        'concat_space' => ['spacing' => 'one'],
+        'include' => true,
+        'new_with_braces' => true,
+        'no_empty_statement' => true,
+        'no_extra_blank_lines' => true,
+        'no_leading_import_slash' => true,
+        'no_leading_namespace_whitespace' => true,
+        'no_multiline_whitespace_around_double_arrow' => true,
+        'multiline_whitespace_before_semicolons' => true,
+        'no_singleline_whitespace_before_semicolons' => true,
+        'no_trailing_comma_in_singleline_array' => true,
+        'no_unused_imports' => true,
+        'no_whitespace_in_blank_line' => true,
+        'object_operator_without_whitespace' => true,
+        'ordered_imports' => true,
+        'standardize_not_equals' => true,
+        'ternary_operator_spaces' => true,
+    ]);
+return $config;