diff --git a/composer.json b/composer.json
index 0b18e94b5..016fadd75 100644
--- a/composer.json
+++ b/composer.json
@@ -30,7 +30,10 @@
         "psr-4": {
             "Psalm\\Plugin\\": "src/Psalm/Plugin",
             "Psalm\\": "src/Psalm"
-        }
+        },
+        "files": [
+            "src/functions.php"
+        ]
     },
     "autoload-dev": {
         "psr-4": {
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 13a9c46e7..fa6da4604 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/5.7/phpunit.xsd"
-         bootstrap="tests/bootstrap.php"
+         bootstrap="vendor/autoload.php"
          backupGlobals="false"
          beStrictAboutCoversAnnotation="true"
          beStrictAboutOutputDuringTests="true"
diff --git a/src/Psalm/Config.php b/src/Psalm/Config.php
index 464a1bf6a..071b2f076 100644
--- a/src/Psalm/Config.php
+++ b/src/Psalm/Config.php
@@ -21,6 +21,8 @@ use Psalm\Progress\Progress;
 use Psalm\Progress\VoidProgress;
 use SimpleXMLElement;
 
+use function isAbsolutePath;
+
 class Config
 {
     const DEFAULT_FILE_NAME = 'psalm.xml';
diff --git a/src/command_functions.php b/src/command_functions.php
index 4f26bbe53..fe781cc10 100644
--- a/src/command_functions.php
+++ b/src/command_functions.php
@@ -222,32 +222,3 @@ function getPathsToCheck($f_paths)
 
     return $paths_to_check;
 }
-
-/**
- * @param string $path
- *
- * @return bool
- */
-function isAbsolutePath($path)
-{
-    // Optional wrapper(s).
-    $regex = '%^(?<wrappers>(?:[[:print:]]{2,}://)*)';
-
-    // Optional root prefix.
-    $regex .= '(?<root>(?:[[:alpha:]]:/|/)?)';
-
-    // Actual path.
-    $regex .= '(?<path>(?:[[:print:]]*))$%';
-
-    $parts = [];
-
-    if (!preg_match($regex, $path, $parts)) {
-        throw new InvalidArgumentException(sprintf('Path is not valid, "%s" given.', $path));
-    }
-
-    if ('' !== $parts['root']) {
-        return true;
-    }
-
-    return false;
-}
diff --git a/src/functions.php b/src/functions.php
new file mode 100644
index 000000000..a84353a7a
--- /dev/null
+++ b/src/functions.php
@@ -0,0 +1,29 @@
+<?php
+/**
+ * @param string $path
+ *
+ * @return bool
+ */
+function isAbsolutePath($path)
+{
+    // Optional wrapper(s).
+    $regex = '%^(?<wrappers>(?:[[:print:]]{2,}://)*)';
+
+    // Optional root prefix.
+    $regex .= '(?<root>(?:[[:alpha:]]:/|/)?)';
+
+    // Actual path.
+    $regex .= '(?<path>(?:[[:print:]]*))$%';
+
+    $parts = [];
+
+    if (!preg_match($regex, $path, $parts)) {
+        throw new InvalidArgumentException(sprintf('Path is not valid, "%s" given.', $path));
+    }
+
+    if ('' !== $parts['root']) {
+        return true;
+    }
+
+    return false;
+}
diff --git a/tests/IsAbsolutePathTest.php b/tests/IsAbsolutePathTest.php
index 8effdbd94..1affc8943 100644
--- a/tests/IsAbsolutePathTest.php
+++ b/tests/IsAbsolutePathTest.php
@@ -13,8 +13,6 @@ class IsAbsolutePathTest extends TestCase
      */
     public function testIsAbsolutePath($path, $expected)
     {
-        require_once __DIR__.'/../src/command_functions.php';
-
         self::assertSame($expected, isAbsolutePath($path));
     }
 
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
deleted file mode 100644
index 1e856ae71..000000000
--- a/tests/bootstrap.php
+++ /dev/null
@@ -1,5 +0,0 @@
-<?php
-
-require_once(__DIR__.'/../src/command_functions.php');
-
-return require_once(__DIR__.'/../vendor/autoload.php');