Integrate PHPStan analysis (#1)

build.xml

@@ -6,7 +6,8 @@
 		composer-install,
 		lint,
 		cs,
-		tests
+		tests,
+		phpstan
 	"/>
 
 	<target name="composer-validate">
@@ -95,4 +96,19 @@
 			<arg path="tests"/>
 		</exec>
 	</target>
+
+	<target name="phpstan">
+		<exec
+			executable="vendor/bin/phpstan"
+			logoutput="true"
+			passthru="true"
+			checkreturn="true"
+		>
+			<arg value="analyse"/>
+			<arg value="--level"/>
+			<arg value="7"/>
+			<arg path="src"/>
+			<arg path="tests"/>
+		</exec>
+	</target>
 </project>

composer.json

@@ -2,6 +2,8 @@
 	"name": "phpstan/phpdoc-parser",
 	"description": "PHPDoc parser with support for nullable, intersection and generic types",
 	"license": "MIT",
+	"minimum-stability": "dev",
+	"prefer-stable": true,
 	"require": {
 		"php": "~7.0"
 	},
@@ -9,10 +11,14 @@
 		"consistence/coding-standard": "^2.0.0",
 		"jakub-onderka/php-parallel-lint": "^0.9.2",
 		"phing/phing": "^2.16.0",
+		"phpstan/phpstan": "^0.9",
 		"phpunit/phpunit": "^6.3",
 		"slevomat/coding-standard": "^3.3.0"
 	},
 	"autoload": {
 		"psr-4": {"PHPStan\\PhpDocParser\\": ["src/"]}
+	},
+	"autoload-dev": {
+		"psr-4": {"PHPStan\\PhpDocParser\\": ["tests/PHPStan"]}
 	}
 }

src/Lexer/Lexer.php

@@ -86,6 +86,8 @@ class Lexer
 		}
 
 		preg_match_all($this->regexp, $s, $tokens, PREG_SET_ORDER);
+
+		assert($this->types !== null);
 		$count = count($this->types);
 
 		foreach ($tokens as &$match) {