Add PHPStan for static analysis (#905)

.github/workflows/ci.yml

@@ -46,8 +46,12 @@ jobs:
           CI_PHP_VERSION: ${{ matrix.php-version }}
           CI_PHP_FUTURE_RELEASE: ${{ matrix.future-release }}
 
-      - name: Static analysis
+      - name: Static analysis - Psalm
         run: 'vendor/bin/psalm --config="tests/psalm.xml"'
         # TODO: Remove exclusion that skips running psalm on PHP 8.4 when psalm
         # supports PHP 8.4 (https://github.com/vimeo/psalm/issues/11107).
-        if: ${{ !matrix.future-release && matrix.php-version < 8.4 }}
+        if: ${{ matrix.php-version < 8.4 }}
+
+      - name: Static analysis - PHPStan
+        run: 'vendor/bin/phpstan analyse --configuration="phpstan.neon" .'
+        if: ${{ matrix.php-version >= 7.4 }}

composer.json

@@ -27,6 +27,7 @@
         "friendsofphp/php-cs-fixer": "*",
         "phpcompatibility/php-compatibility": "dev-develop",
         "phpcsstandards/phpcsutils": "@alpha",
+        "phpstan/phpstan": "*",
         "phpunit/phpunit": "*",
         "squizlabs/php_codesniffer": "*"
     },

phpstan-baseline.neon

@@ -0,0 +1,13 @@
+parameters:
+    ignoreErrors:
+        -
+            message: '#^Class CurlHandle not found\.$#'
+            identifier: class.notFound
+            count: 2
+            path: src/Curl/Curl.php
+
+        -
+            message: '#^Class CurlMultiHandle not found\.$#'
+            identifier: class.notFound
+            count: 2
+            path: src/Curl/MultiCurl.php

phpstan.neon

@@ -0,0 +1,15 @@
+includes:
+    - phpstan-baseline.neon
+
+parameters:
+    reportUnmatchedIgnoredErrors: false
+
+    # TODO: Increase rule level to be more strict.
+    level: 0
+
+    # TODO: Remove all exclusions except vendor/ and fix related errors.
+    excludePaths:
+        - examples/*
+        - tests/*
+        - vendor/*
+        - www/*