diff --git a/psalm.xml b/psalm.xml
index 753b3946e..ea1157dd8 100644
--- a/psalm.xml
+++ b/psalm.xml
@@ -11,6 +11,7 @@
         <directory name="tests" />
         <ignoreFiles>
             <file name="src/Psalm/CallMap.php" />
+            <directory name="tests/stubs" />
         </ignoreFiles>
     </projectFiles>
 
diff --git a/tests/AnnotationTest.php b/tests/AnnotationTest.php
index cce4d3001..0b59b8f6d 100644
--- a/tests/AnnotationTest.php
+++ b/tests/AnnotationTest.php
@@ -12,6 +12,9 @@ class AnnotationTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class AnnotationTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class AnnotationTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/ArgTest.php b/tests/ArgTest.php
index 549adbb1e..5403e7a43 100644
--- a/tests/ArgTest.php
+++ b/tests/ArgTest.php
@@ -12,6 +12,9 @@ class ArgTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class ArgTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class ArgTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/ArrayAccessTest.php b/tests/ArrayAccessTest.php
index d6bb7bd40..28da771de 100644
--- a/tests/ArrayAccessTest.php
+++ b/tests/ArrayAccessTest.php
@@ -28,9 +28,9 @@ class ArrayAccessTest extends PHPUnit_Framework_TestCase
      */
     public function setUp()
     {
-        $config = new TestConfig();
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(new TestConfig());
     }
 
     /**
diff --git a/tests/ArrayAssignmentTest.php b/tests/ArrayAssignmentTest.php
index b6273c527..3471c1504 100644
--- a/tests/ArrayAssignmentTest.php
+++ b/tests/ArrayAssignmentTest.php
@@ -29,9 +29,9 @@ class ArrayAssignmentTest extends PHPUnit_Framework_TestCase
      */
     public function setUp()
     {
-        $config = new TestConfig();
         \Psalm\Checker\FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(new TestConfig());
     }
 
     /**
diff --git a/tests/AssignmentTest.php b/tests/AssignmentTest.php
index db807a26d..e9998c202 100644
--- a/tests/AssignmentTest.php
+++ b/tests/AssignmentTest.php
@@ -12,6 +12,9 @@ class AssignmentTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class AssignmentTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class AssignmentTest extends PHPUnit_Framework_TestCase
     {
         \Psalm\Checker\FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/BinaryOperationTest.php b/tests/BinaryOperationTest.php
index b41dd83dc..a0822be09 100644
--- a/tests/BinaryOperationTest.php
+++ b/tests/BinaryOperationTest.php
@@ -30,7 +30,7 @@ class BinaryOperationTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
-        $config = new TestConfig();
+        $this->project_checker->setConfig(new TestConfig());
     }
 
     /**
diff --git a/tests/ClassScopeTest.php b/tests/ClassScopeTest.php
index 9607fefb9..d79a87e56 100644
--- a/tests/ClassScopeTest.php
+++ b/tests/ClassScopeTest.php
@@ -12,6 +12,9 @@ class ClassScopeTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class ClassScopeTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class ClassScopeTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/ClassTest.php b/tests/ClassTest.php
index 9b60a3690..a2e3d7ca1 100644
--- a/tests/ClassTest.php
+++ b/tests/ClassTest.php
@@ -28,9 +28,9 @@ class ClassTest extends PHPUnit_Framework_TestCase
      */
     public function setUp()
     {
-        $config = new TestConfig();
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(new TestConfig());
     }
 
     /**
diff --git a/tests/ClosureTest.php b/tests/ClosureTest.php
index 640140e7f..3d1d98392 100644
--- a/tests/ClosureTest.php
+++ b/tests/ClosureTest.php
@@ -12,6 +12,9 @@ class ClosureTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class ClosureTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class ClosureTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/ConfigTest.php b/tests/ConfigTest.php
index 7595bdb5a..80e6f7023 100644
--- a/tests/ConfigTest.php
+++ b/tests/ConfigTest.php
@@ -5,12 +5,28 @@ use PhpParser\ParserFactory;
 use PHPUnit_Framework_TestCase;
 use Psalm\Checker\FileChecker;
 use Psalm\Config;
+use Psalm\Context;
 
 class ConfigTest extends PHPUnit_Framework_TestCase
 {
+    /** @var \PhpParser\Parser */
+    protected static $parser;
+
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
+    /**
+     * @return void
+     */
+    public static function setUpBeforeClass()
+    {
+        self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
+        self::$config = new TestConfig();
+    }
+
     /**
      * @return void
      */
@@ -52,12 +68,15 @@ class ConfigTest extends PHPUnit_Framework_TestCase
      */
     public function testBarebonesConfig()
     {
-        $config = Config::loadFromXML('psalm.xml', '<?xml version="1.0"?>
-<psalm>
-    <projectFiles>
-        <directory name="src" />
-    </projectFiles>
-</psalm>');
+        $config = Config::loadFromXML(
+            'psalm.xml',
+            '<?xml version="1.0"?>
+            <psalm>
+                <projectFiles>
+                    <directory name="src" />
+                </projectFiles>
+            </psalm>'
+        );
 
         $this->assertTrue($config->isInProjectDirs(realpath('src/Psalm/Type.php')));
         $this->assertFalse($config->isInProjectDirs(realpath('examples/StringChecker.php')));
@@ -68,15 +87,18 @@ class ConfigTest extends PHPUnit_Framework_TestCase
      */
     public function testIgnoreProjectDirectory()
     {
-        $config = Config::loadFromXML('psalm.xml', '<?xml version="1.0"?>
-<psalm>
-    <projectFiles>
-        <directory name="src" />
-        <ignoreFiles>
-            <directory name="src/Psalm/Checker" />
-        </ignoreFiles>
-    </projectFiles>
-</psalm>');
+        $config = Config::loadFromXML(
+            'psalm.xml',
+            '<?xml version="1.0"?>
+            <psalm>
+                <projectFiles>
+                    <directory name="src" />
+                    <ignoreFiles>
+                        <directory name="src/Psalm/Checker" />
+                    </ignoreFiles>
+                </projectFiles>
+            </psalm>'
+        );
 
         $this->assertTrue($config->isInProjectDirs(realpath('src/Psalm/Type.php')));
         $this->assertFalse($config->isInProjectDirs(realpath('src/Psalm/Checker/FileChecker.php')));
@@ -88,17 +110,20 @@ class ConfigTest extends PHPUnit_Framework_TestCase
      */
     public function testIssueHandler()
     {
-        $config = Config::loadFromXML('psalm.xml', '<?xml version="1.0"?>
-<psalm>
-    <projectFiles>
-        <directory name="src" />
-        <directory name="tests" />
-    </projectFiles>
+        $config = Config::loadFromXML(
+            'psalm.xml',
+            '<?xml version="1.0"?>
+            <psalm>
+                <projectFiles>
+                    <directory name="src" />
+                    <directory name="tests" />
+                </projectFiles>
 
-    <issueHandlers>
-        <MissingReturnType errorLevel="suppress" />
-    </issueHandlers>
-</psalm>');
+                <issueHandlers>
+                    <MissingReturnType errorLevel="suppress" />
+                </issueHandlers>
+            </psalm>'
+        );
 
         $this->assertTrue($config->excludeIssueInFile('MissingReturnType', realpath('tests/ConfigTest.php')));
         $this->assertTrue($config->excludeIssueInFile('MissingReturnType', realpath('src/Psalm/Type.php')));
@@ -109,24 +134,27 @@ class ConfigTest extends PHPUnit_Framework_TestCase
      */
     public function testIssueHandlerWithCustomErrorLevels()
     {
-        $config = Config::loadFromXML('psalm.xml', '<?xml version="1.0"?>
-<psalm>
-    <projectFiles>
-        <directory name="src" />
-        <directory name="tests" />
-    </projectFiles>
+        $config = Config::loadFromXML(
+            'psalm.xml',
+            '<?xml version="1.0"?>
+            <psalm>
+                <projectFiles>
+                    <directory name="src" />
+                    <directory name="tests" />
+                </projectFiles>
 
-    <issueHandlers>
-        <MissingReturnType errorLevel="info">
-            <errorLevel type="suppress">
-                <directory name="tests" />
-            </errorLevel>
-            <errorLevel type="error">
-                <directory name="src/Psalm/Checker" />
-            </errorLevel>
-        </MissingReturnType>
-    </issueHandlers>
-</psalm>');
+                <issueHandlers>
+                    <MissingReturnType errorLevel="info">
+                        <errorLevel type="suppress">
+                            <directory name="tests" />
+                        </errorLevel>
+                        <errorLevel type="error">
+                            <directory name="src/Psalm/Checker" />
+                        </errorLevel>
+                    </MissingReturnType>
+                </issueHandlers>
+            </psalm>'
+        );
 
         $this->assertTrue($config->excludeIssueInFile('MissingReturnType', realpath('tests/ConfigTest.php')));
         $this->assertFalse($config->excludeIssueInFile('MissingReturnType', realpath('src/Psalm/Type.php')));
@@ -155,16 +183,19 @@ class ConfigTest extends PHPUnit_Framework_TestCase
             )
         );
 
-        $config = Config::loadFromXML('psalm.xml', '<?xml version="1.0"?>
-<psalm>
-    <projectFiles>
-        <directory name="src" />
-    </projectFiles>
+        $config = Config::loadFromXML(
+            'psalm.xml',
+            '<?xml version="1.0"?>
+            <psalm>
+                <projectFiles>
+                    <directory name="src" />
+                </projectFiles>
 
-    <issueHandlers>
-    ' . $all_possible_handlers . '
-    </issueHandlers>
-</psalm>');
+                <issueHandlers>
+                ' . $all_possible_handlers . '
+                </issueHandlers>
+            </psalm>'
+        );
     }
 
     /**
@@ -174,15 +205,104 @@ class ConfigTest extends PHPUnit_Framework_TestCase
      */
     public function testImpossibleIssue()
     {
-        $config = Config::loadFromXML('psalm.xml', '<?xml version="1.0"?>
-<psalm>
-    <projectFiles>
-        <directory name="src" />
-    </projectFiles>
+        $config = Config::loadFromXML(
+            'psalm.xml',
+            '<?xml version="1.0"?>
+            <psalm>
+                <projectFiles>
+                    <directory name="src" />
+                </projectFiles>
 
-    <issueHandlers>
-        <ImpossibleIssue errorLevel="suppress" />
-    </issueHandlers>
-</psalm>');
+                <issueHandlers>
+                    <ImpossibleIssue errorLevel="suppress" />
+                </issueHandlers>
+            </psalm>'
+        );
+    }
+
+    /**
+     * @expectedException        \Psalm\Exception\ConfigException
+     * @expectedExceptionMessage Cannot resolve stubfile path
+     * @return                   void
+     */
+    public function testNonexistentStubFile()
+    {
+        $config = Config::loadFromXML(
+            'psalm.xml',
+            '<?xml version="1.0"?>
+            <psalm>
+                <projectFiles>
+                    <directory name="src" />
+                </projectFiles>
+
+                <stubs>
+                    <file name="stubs/invalidfile.php" />
+                </stubs>
+            </psalm>'
+        );
+    }
+
+    /**
+     * @return void
+     */
+    public function testStubFile()
+    {
+        $this->project_checker->setConfig(
+            TestConfig::loadFromXML(
+                'psalm.xml',
+                '<?xml version="1.0"?>
+                <psalm>
+                    <projectFiles>
+                        <directory name="src" />
+                    </projectFiles>
+
+                    <stubs>
+                        <file name="tests/stubs/systemclass.php" />
+                    </stubs>
+                </psalm>'
+            )
+        );
+
+        $stmts = self::$parser->parse('<?php
+        $a = new SystemClass();
+        echo SystemClass::HELLO;
+
+        $b = $a->foo(5, "hello");
+        $c = SystemClass::bar(5, "hello");
+        ');
+
+        $file_checker = new FileChecker(getcwd() . '/src/somefile.php', $this->project_checker, $stmts);
+        $context = new Context();
+        $file_checker->visitAndAnalyzeMethods($context);
+    }
+
+    /**
+     * @return void
+     */
+    public function testStubFileWithExistingClassDefinition()
+    {
+        $this->project_checker->setConfig(
+            TestConfig::loadFromXML(
+                'psalm.xml',
+                '<?xml version="1.0"?>
+                <psalm>
+                    <projectFiles>
+                        <directory name="src" />
+                    </projectFiles>
+
+                    <stubs>
+                        <file name="tests/stubs/logicexception.php" />
+                    </stubs>
+                </psalm>'
+            )
+        );
+
+        $stmts = self::$parser->parse('<?php
+        $a = new LogicException("bad");
+        ');
+
+        $file_checker = new FileChecker(getcwd() . '/src/somefile.php', $this->project_checker, $stmts);
+        $context = new Context();
+        $file_checker->visitAndAnalyzeMethods($context);
     }
 }
diff --git a/tests/ConstantTest.php b/tests/ConstantTest.php
index 4fd9243ef..39ed07b19 100644
--- a/tests/ConstantTest.php
+++ b/tests/ConstantTest.php
@@ -12,6 +12,9 @@ class ConstantTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class ConstantTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class ConstantTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/ForTest.php b/tests/ForTest.php
index 6207b33dc..1434680d0 100644
--- a/tests/ForTest.php
+++ b/tests/ForTest.php
@@ -12,6 +12,9 @@ class ForTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class ForTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class ForTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/ForbiddenCodeTest.php b/tests/ForbiddenCodeTest.php
index 9a021d9bc..bf6a1130e 100644
--- a/tests/ForbiddenCodeTest.php
+++ b/tests/ForbiddenCodeTest.php
@@ -12,6 +12,9 @@ class ForbiddenCodeTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class ForbiddenCodeTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class ForbiddenCodeTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/ForeachTest.php b/tests/ForeachTest.php
index 379c46d4d..e2a5f81bf 100644
--- a/tests/ForeachTest.php
+++ b/tests/ForeachTest.php
@@ -12,6 +12,9 @@ class ForeachTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class ForeachTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class ForeachTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/FunctionCallTest.php b/tests/FunctionCallTest.php
index 0178b92fb..da22f8555 100644
--- a/tests/FunctionCallTest.php
+++ b/tests/FunctionCallTest.php
@@ -28,9 +28,9 @@ class FunctionCallTest extends PHPUnit_Framework_TestCase
      */
     public function setUp()
     {
-        $config = new TestConfig();
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(new TestConfig());
     }
 
     /**
diff --git a/tests/IncludeTest.php b/tests/IncludeTest.php
index fa2884266..4f399c29f 100644
--- a/tests/IncludeTest.php
+++ b/tests/IncludeTest.php
@@ -11,6 +11,9 @@ class IncludeTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -20,6 +23,7 @@ class IncludeTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
+        self::$config = new TestConfig();
     }
 
     /**
@@ -27,10 +31,9 @@ class IncludeTest extends PHPUnit_Framework_TestCase
      */
     public function setUp()
     {
-        $config = new TestConfig();
-        $config->throw_exception = true;
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/InterfaceTest.php b/tests/InterfaceTest.php
index 393c3f660..108c2a991 100644
--- a/tests/InterfaceTest.php
+++ b/tests/InterfaceTest.php
@@ -21,8 +21,6 @@ class InterfaceTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
     }
 
     /**
@@ -32,6 +30,7 @@ class InterfaceTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(new TestConfig());
     }
 
     /**
diff --git a/tests/IssueSuppressionTest.php b/tests/IssueSuppressionTest.php
index f1b5fc877..8fe404190 100644
--- a/tests/IssueSuppressionTest.php
+++ b/tests/IssueSuppressionTest.php
@@ -27,10 +27,9 @@ class IssueSuppressionTest extends PHPUnit_Framework_TestCase
      */
     public function setUp()
     {
-        $config = new TestConfig();
-        $config->throw_exception = true;
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(new TestConfig());
     }
 
     /**
diff --git a/tests/JsonOutputTest.php b/tests/JsonOutputTest.php
index fe835c381..aa203567c 100644
--- a/tests/JsonOutputTest.php
+++ b/tests/JsonOutputTest.php
@@ -23,10 +23,6 @@ class JsonOutputTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
-        $config->throw_exception = false;
-        $config->stop_on_first_error = false;
     }
 
     /**
@@ -36,6 +32,11 @@ class JsonOutputTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+
+        $config = new TestConfig();
+        $config->throw_exception = false;
+        $config->stop_on_first_error = false;
+        $this->project_checker->setConfig($config);
     }
 
     /**
diff --git a/tests/ListTest.php b/tests/ListTest.php
index b1b585bb6..942b1d553 100644
--- a/tests/ListTest.php
+++ b/tests/ListTest.php
@@ -12,6 +12,9 @@ class ListTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class ListTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class ListTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/MethodCallTest.php b/tests/MethodCallTest.php
index a298c2642..7d4192154 100644
--- a/tests/MethodCallTest.php
+++ b/tests/MethodCallTest.php
@@ -28,9 +28,9 @@ class MethodCallTest extends PHPUnit_Framework_TestCase
      */
     public function setUp()
     {
-        $config = new TestConfig();
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(new TestConfig());
     }
 
     /**
diff --git a/tests/MethodMutationTest.php b/tests/MethodMutationTest.php
index 3b801533d..b8f852d7c 100644
--- a/tests/MethodMutationTest.php
+++ b/tests/MethodMutationTest.php
@@ -13,6 +13,9 @@ class MethodMutationTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -22,6 +25,7 @@ class MethodMutationTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
+        self::$config = new TestConfig();
     }
 
     /**
@@ -29,9 +33,9 @@ class MethodMutationTest extends PHPUnit_Framework_TestCase
      */
     public function setUp()
     {
-        $config = new TestConfig();
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/MethodSignatureTest.php b/tests/MethodSignatureTest.php
index b3a13471d..555d0a068 100644
--- a/tests/MethodSignatureTest.php
+++ b/tests/MethodSignatureTest.php
@@ -12,6 +12,9 @@ class MethodSignatureTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class MethodSignatureTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class MethodSignatureTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/NamespaceTest.php b/tests/NamespaceTest.php
index 87632923f..28b5cca4f 100644
--- a/tests/NamespaceTest.php
+++ b/tests/NamespaceTest.php
@@ -12,6 +12,9 @@ class NamespaceTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class NamespaceTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class NamespaceTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/Php40Test.php b/tests/Php40Test.php
index 81d4647ac..9029b2fa0 100644
--- a/tests/Php40Test.php
+++ b/tests/Php40Test.php
@@ -12,6 +12,9 @@ class Php40Test extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class Php40Test extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class Php40Test extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/Php55Test.php b/tests/Php55Test.php
index f48d82c3d..83ee11b69 100644
--- a/tests/Php55Test.php
+++ b/tests/Php55Test.php
@@ -12,6 +12,9 @@ class Php55Test extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class Php55Test extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class Php55Test extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/Php56Test.php b/tests/Php56Test.php
index dc71f9ef2..3a18e9712 100644
--- a/tests/Php56Test.php
+++ b/tests/Php56Test.php
@@ -12,6 +12,9 @@ class Php56Test extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,6 +24,7 @@ class Php56Test extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
+        self::$config = new TestConfig();
     }
 
     /**
@@ -28,9 +32,9 @@ class Php56Test extends PHPUnit_Framework_TestCase
      */
     public function setUp()
     {
-        $config = new TestConfig();
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/Php70Test.php b/tests/Php70Test.php
index 92c98d684..f6d4592df 100644
--- a/tests/Php70Test.php
+++ b/tests/Php70Test.php
@@ -28,9 +28,9 @@ class Php70Test extends PHPUnit_Framework_TestCase
      */
     public function setUp()
     {
-        $config = new TestConfig();
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(new TestConfig());
     }
 
     /**
diff --git a/tests/Php71Test.php b/tests/Php71Test.php
index f2ca570ad..6fc027aae 100644
--- a/tests/Php71Test.php
+++ b/tests/Php71Test.php
@@ -12,6 +12,9 @@ class Php71Test extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,6 +24,7 @@ class Php71Test extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
+        self::$config = new TestConfig();
     }
 
     /**
@@ -28,11 +32,9 @@ class Php71Test extends PHPUnit_Framework_TestCase
      */
     public function setUp()
     {
-        $config = new TestConfig();
-        $config->use_docblock_types = true;
-
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/PropertyTypeTest.php b/tests/PropertyTypeTest.php
index 8347448fa..dcbdaeca7 100644
--- a/tests/PropertyTypeTest.php
+++ b/tests/PropertyTypeTest.php
@@ -28,10 +28,9 @@ class PropertyTypeTest extends PHPUnit_Framework_TestCase
      */
     public function setUp()
     {
-        $config = new TestConfig();
-        $config->throw_exception = true;
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(new TestConfig());
     }
 
     /**
diff --git a/tests/ReturnTypeTest.php b/tests/ReturnTypeTest.php
index 748b66605..c2a0b7fb2 100644
--- a/tests/ReturnTypeTest.php
+++ b/tests/ReturnTypeTest.php
@@ -12,6 +12,9 @@ class ReturnTypeTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class ReturnTypeTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class ReturnTypeTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/ScopeTest.php b/tests/ScopeTest.php
index 819244aff..458958181 100644
--- a/tests/ScopeTest.php
+++ b/tests/ScopeTest.php
@@ -12,6 +12,9 @@ class ScopeTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,8 +24,7 @@ class ScopeTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -32,6 +34,7 @@ class ScopeTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/SwitchTypeTest.php b/tests/SwitchTypeTest.php
index a9c415235..317792470 100644
--- a/tests/SwitchTypeTest.php
+++ b/tests/SwitchTypeTest.php
@@ -14,6 +14,9 @@ class SwitchTypeTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -23,8 +26,7 @@ class SwitchTypeTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -34,6 +36,7 @@ class SwitchTypeTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/ToStringTest.php b/tests/ToStringTest.php
index ce1f5de35..2de34ec34 100644
--- a/tests/ToStringTest.php
+++ b/tests/ToStringTest.php
@@ -12,6 +12,9 @@ class ToStringTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,6 +24,7 @@ class ToStringTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
+        self::$config = new TestConfig();
     }
 
     /**
@@ -28,9 +32,9 @@ class ToStringTest extends PHPUnit_Framework_TestCase
      */
     public function setUp()
     {
-        $config = new TestConfig();
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/TraitTest.php b/tests/TraitTest.php
index 4849ccf06..503a0901d 100644
--- a/tests/TraitTest.php
+++ b/tests/TraitTest.php
@@ -12,6 +12,9 @@ class TraitTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,6 +24,7 @@ class TraitTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
+        self::$config = new TestConfig();
     }
 
     /**
@@ -28,9 +32,9 @@ class TraitTest extends PHPUnit_Framework_TestCase
      */
     public function setUp()
     {
-        $config = new TestConfig();
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/TypeCombinationTest.php b/tests/TypeCombinationTest.php
index b5e4d20fb..477a75067 100644
--- a/tests/TypeCombinationTest.php
+++ b/tests/TypeCombinationTest.php
@@ -11,6 +11,9 @@ class TypeCombinationTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -20,6 +23,7 @@ class TypeCombinationTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
+        self::$config = new TestConfig();
     }
 
     /**
@@ -29,6 +33,7 @@ class TypeCombinationTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/TypeParseTest.php b/tests/TypeParseTest.php
index b9cd5d8aa..36047689e 100644
--- a/tests/TypeParseTest.php
+++ b/tests/TypeParseTest.php
@@ -10,6 +10,9 @@ class TypeParseTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -19,6 +22,7 @@ class TypeParseTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
+        self::$config = new TestConfig();
     }
 
     /**
diff --git a/tests/TypeReconciliationTest.php b/tests/TypeReconciliationTest.php
index 909e038e3..7f49a8d83 100644
--- a/tests/TypeReconciliationTest.php
+++ b/tests/TypeReconciliationTest.php
@@ -16,6 +16,9 @@ class TypeReconciliationTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -28,8 +31,7 @@ class TypeReconciliationTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
+        self::$config = new TestConfig();
     }
 
     /**
@@ -38,12 +40,12 @@ class TypeReconciliationTest extends PHPUnit_Framework_TestCase
     public function setUp()
     {
         FileChecker::clearCache();
-        $this->project_checker = new \Psalm\Checker\ProjectChecker();
+
+        $this->project_checker = new ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
 
         $this->file_checker = new FileChecker('somefile.php', $this->project_checker);
         $this->file_checker->context = new Context();
-
-        $this->project_checker = new ProjectChecker();
     }
 
     /**
diff --git a/tests/TypeTest.php b/tests/TypeTest.php
index cd41ecd60..da76497bb 100644
--- a/tests/TypeTest.php
+++ b/tests/TypeTest.php
@@ -12,6 +12,9 @@ class TypeTest extends PHPUnit_Framework_TestCase
     /** @var \PhpParser\Parser */
     protected static $parser;
 
+    /** @var TestConfig */
+    protected static $config;
+
     /** @var \Psalm\Checker\ProjectChecker */
     protected $project_checker;
 
@@ -21,9 +24,7 @@ class TypeTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
-
-        $config = new TestConfig();
-        $config->throw_exception = true;
+        self::$config = new TestConfig();
     }
 
     /**
@@ -33,6 +34,7 @@ class TypeTest extends PHPUnit_Framework_TestCase
     {
         FileChecker::clearCache();
         $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
     }
 
     /**
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index ec55bd438..55d15f200 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -2,6 +2,7 @@
 
 ini_set('display_startup_errors', 1);
 ini_set('html_errors', 1);
+ini_set('memory_limit', '-1');
 error_reporting(E_ALL);
 
 foreach ([__DIR__ . '/../../../autoload.php', __DIR__ . '/../vendor/autoload.php'] as $file) {
diff --git a/tests/stubs/logicexception.php b/tests/stubs/logicexception.php
new file mode 100644
index 000000000..9def7d8be
--- /dev/null
+++ b/tests/stubs/logicexception.php
@@ -0,0 +1,8 @@
+<?php
+
+class LogicException extends Exception {
+    /**
+     * @param int $a
+     */
+    public function __construct($a) {}
+}
diff --git a/tests/stubs/systemclass.php b/tests/stubs/systemclass.php
new file mode 100644
index 000000000..fc42255b4
--- /dev/null
+++ b/tests/stubs/systemclass.php
@@ -0,0 +1,19 @@
+<?php
+
+class SystemClass  {
+    const HELLO = 'hello';
+
+    /**
+     * @param int       $a
+     * @param string    $b
+     * @return string
+     */
+    public function foo($a, $b) {}
+
+    /**
+     * @param int       $a
+     * @param string    $b
+     * @return string
+     */
+    public static function bar($a, $b) {}
+}