Pin versions and run psalm too

.gitattributes

@@ -10,6 +10,7 @@
 /phpstan.neon.dist export-ignore
 /phpstan.tests.neon.dist export-ignore
 /phpunit.xml.dist export-ignore
+/psalm.xml export-ignore
 /README.md export-ignore
 /UPGRADING.md export-ignore
 /vendor-bin export-ignore

.github/CONTRIBUTING.md

@@ -18,13 +18,13 @@ We accept contributions via pull requests on Github. Please review these guideli
 First, install the dependencies using [Composer](https://getcomposer.org/):
 
 ```bash
-$ composer install
+$ make install
 ```
 
-Then run [PHPUnit](https://phpunit.de/):
+Then run [PHPUnit](https://phpunit.de/) and the static analyzers:
 
 ```bash
-$ vendor/bin/phpunit
+$ make test
 ```
 
-The tests will be automatically run by [Travis CI](https://travis-ci.org/) and [GitHub Actions](https://github.com/features/actions) against pull requests.
+These will also be automatically run by [Travis CI](https://travis-ci.org/) and [GitHub Actions](https://github.com/features/actions) against pull requests.

Makefile

@@ -0,0 +1,23 @@
+install:
+	@docker run -it -w /data -v ${PWD}:/data:delegated -v ~/.composer:/root/.composer:delegated --entrypoint composer --rm registry.gitlab.com/grahamcampbell/php:7.4-base update
+	@docker run -it -w /data -v ${PWD}:/data:delegated -v ~/.composer:/root/.composer:delegated --entrypoint composer --rm registry.gitlab.com/grahamcampbell/php:7.4-base bin all update
+
+phpunit:
+	@rm -f bootstrap/cache/*.php && docker run -it -w /data -v ${PWD}:/data:delegated --entrypoint vendor/bin/phpunit --rm registry.gitlab.com/grahamcampbell/php:7.4-cli
+
+phpstan-analyze-src:
+	@docker run -it -w /data -v ${PWD}:/data:delegated --entrypoint vendor/bin/phpstan --rm registry.gitlab.com/grahamcampbell/php:7.4-cli analyze src -c phpstan.src.neon.dist
+
+phpstan-analyze-tests:
+	@docker run -it -w /data -v ${PWD}:/data:delegated --entrypoint vendor/bin/phpstan --rm registry.gitlab.com/grahamcampbell/php:7.4-cli analyze tests -c phpstan.tests.neon.dist
+
+psalm-analyze:
+	@docker run -it -w /data -v ${PWD}:/data:delegated --entrypoint vendor/bin/psalm --rm registry.gitlab.com/grahamcampbell/php:7.4-cli
+
+psalm-show-info:
+	@docker run -it -w /data -v ${PWD}:/data:delegated --entrypoint vendor/bin/psalm --rm registry.gitlab.com/grahamcampbell/php:7.4-cli --show-info=true
+
+test: phpunit phpstan-analyze-src phpstan-analyze-tests psalm-analyze
+
+clean:
+	@rm -rf .phpunit.result.cache composer.lock vendor vendor-bin/*/composer.lock vendor-bin/*/vendor

psalm.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0"?>
+<psalm
+    errorLevel="4"
+    resolveFromConfigFile="true"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xmlns="https://getpsalm.org/schema/config"
+    xsi:schemaLocation="https://getpsalm.org/schema/config vendor/vimeo/psalm/config.xsd"
+>
+    <projectFiles>
+        <directory name="src" />
+    </projectFiles>
+</psalm>

vendor-bin/phpstan/composer.json

@@ -1,9 +1,12 @@
 {
     "require": {
-        "phpstan/phpstan": "^0.12.25",
-        "phpstan/extension-installer": "^1.0.4",
-        "phpstan/phpstan-deprecation-rules": "^0.12.4",
-        "phpstan/phpstan-strict-rules": "^0.12.2",
-        "thecodingmachine/phpstan-strict-rules": "^0.12.0"
+        "phpstan/phpstan": "~0.12.32",
+        "phpstan/extension-installer": "~1.0.4",
+        "phpstan/phpstan-deprecation-rules": "~0.12.4",
+        "phpstan/phpstan-strict-rules": "~0.12.2",
+        "thecodingmachine/phpstan-strict-rules": "~0.12.0"
+    },
+    "config": {
+        "preferred-install": "dist"
     }
 }

vendor-bin/psalm/composer.json

@@ -0,0 +1,8 @@
+{
+    "require": {
+        "vimeo/psalm": "~3.12.2"
+    },
+    "config": {
+        "preferred-install": "dist"
+    }
+}