Add README

Author: sasezaki

README.md

@@ -0,0 +1,39 @@
+sfp-psalm-psr-log-plugin
+========================
+
+PSR-3 (psr/log) plugin for [Psalm](https://github.com/vimeo/psalm)
+
+Installation:
+
+```console
+$ composer require --dev struggle-for-php/sfp-psalm-psr-log-plugin
+$ vendor/bin/psalm-plugin enable struggle-for-php/sfp-psalm-psr-log-plugin
+```
+
+## Example
+
+```php
+<?php
+
+use Psr\Log\LoggerInterface;
+
+class Foo
+{
+    /** @var LoggerInterface */
+    private $logger;
+
+    public function anyAction()
+    {
+        try {
+        } catch (\Exception $e) {
+            $this->logger->error('error happend.', ['exception' => $e->getMessage()]);
+        }
+    }
+}
+```
+
+would be ERROR output:
+```php
+ERROR: InvalidArgument - src/Foo.php:14:45 - Argument 2 of Psr\Log\LoggerInterface::error expects array{exception?: Exception}, array{exception: string} provided
+            $this->logger->error('error happend.', ['exception' => $e->getMessage()]);
+```