add Psalm linter

.github/workflows/styles.yml

@@ -46,18 +46,18 @@ jobs:
 #      - run: composer install --prefer-dist
 #      - run: ./vendor/bin/phpstan analyse ./src ./tests --error-format=checkstyle | cs2pr
 
-#  psalm:
-#    name: psalm
-#    runs-on: ubuntu-latest
-#    steps:
-#      - name: Setup PHP
-#        uses: shivammathur/setup-php@v2
-#        with:
-#          php-version: '7.4'
-#          extensions: mbstring, intl, gd, xml, dom, json, fileinfo, curl, zip, iconv
-#      - uses: actions/checkout@v2
-#      - run: composer install --prefer-dist
-#      - run: ./vendor/bin/psalm --output-format=github
+  psalm:
+    name: psalm
+    runs-on: ubuntu-latest
+    steps:
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: '7.4'
+          extensions: mbstring, intl, gd, xml, dom, json, fileinfo, curl, zip, iconv
+      - uses: actions/checkout@v2
+      - run: composer install --prefer-dist
+      - run: ./vendor/bin/psalm --output-format=github
 
 #  security-checker:
 #    name: security-checker

CHANGELOG.md

@@ -7,6 +7,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased]
 ### Added
 - add Github Actions integration
+- add Psalm linter
 
 ## 1.0.0 - 2019-10-08
 ### Changed

composer.json

@@ -3,7 +3,7 @@
   "description": "Super-simple, minimum abstraction TrustedShops API v2.x wrapper, in PHP",
   "license": "MIT",
   "require": {
-    "php": ">=7.0",
+    "php": ">=7.4",
     "ext-curl": "*",
     "ext-json": "*"
   },
@@ -14,7 +14,8 @@
     "friendsofphp/php-cs-fixer": "^2.12",
     "phpmd/phpmd": "^2.6",
     "php-coveralls/php-coveralls": "^2.1",
-    "php-mock/php-mock-phpunit": "^2.4"
+    "php-mock/php-mock-phpunit": "^2.4",
+    "vimeo/psalm": "^4.30"
   },
   "autoload": {
     "psr-4": {