diff --git a/flake8/processor.py b/flake8/processor.py
index 1dc27a1..bcb33cc 100644
--- a/flake8/processor.py
+++ b/flake8/processor.py
@@ -46,14 +46,16 @@ class FileProcessor(object):
 
     NOQA_FILE = re.compile(r'\s*# flake8[:=]\s*noqa', re.I)
 
-    def __init__(self, filename, options):
+    def __init__(self, filename, options, lines=None):
         """Initialice our file processor.
 
         :param str filename:
             Name of the file to process
         """
         self.filename = filename
-        self.lines = self.read_lines()
+        self.lines = lines
+        if lines is None:
+            self.lines = self.read_lines()
         self.strip_utf_bom()
         self.options = options
 
diff --git a/run_tests.py b/run_tests.py
deleted file mode 100755
index 09d6884..0000000
--- a/run_tests.py
+++ /dev/null
@@ -1,32 +0,0 @@
-#!/usr/bin/env python
-
-import unittest
-import os
-import re
-import sys
-sys.path.insert(0, '.')
-
-TEST_DIR = 'flake8.tests'
-
-
-def collect_tests():
-    # list files in directory tests/
-    names = os.listdir(TEST_DIR.replace('.', '/'))
-    regex = re.compile("(?!_+)\w+\.py$")
-    join = '.'.join
-    # Make a list of the names like 'tests.test_name'
-    names = [join([TEST_DIR, f[:-3]]) for f in names if regex.match(f)]
-    modules = [__import__(name, fromlist=[TEST_DIR]) for name in names]
-    load_tests = unittest.defaultTestLoader.loadTestsFromModule
-    suites = [load_tests(m) for m in modules]
-    suite = suites.pop()
-    for s in suites:
-        suite.addTests(s)
-    return suite
-
-if __name__ == "__main__":
-    suite = collect_tests()
-    res = unittest.TextTestRunner(verbosity=1).run(suite)
-
-    # If it was successful, we don't want to exit with code 1
-    raise SystemExit(not res.wasSuccessful())
diff --git a/tests/unit/test_file_processor.py b/tests/unit/test_file_processor.py
index e26bc83..2970697 100644
--- a/tests/unit/test_file_processor.py
+++ b/tests/unit/test_file_processor.py
@@ -1,26 +1,33 @@
-"""Tests for the FileChecker class."""
-from flake8 import checker
+"""Tests for the FileProcessor class."""
+import optparse
+
+from flake8 import processor
 
 import pytest
 
 
+def options_from(**kwargs):
+    kwargs.setdefault('hang_closing', True)
+    kwargs.setdefault('max_line_length', 79)
+    kwargs.setdefault('verbose', False)
+    return optparse.Values(kwargs)
+
+
 def test_read_lines_splits_lines():
     """Verify that read_lines splits the lines of the file."""
-    file_checker = checker.FileChecker(__file__, [])
-    lines = file_checker.read_lines()
+    file_processor = processor.FileProcessor(__file__, options_from())
+    lines = file_processor.lines
     assert len(lines) > 5
-    assert '"""Tests for the FileChecker class."""\n' in lines
+    assert '"""Tests for the FileProcessor class."""\n' in lines
 
 
 @pytest.mark.parametrize('first_line', [
     '\xEF\xBB\xBF"""Module docstring."""\n',
-    '\uFEFF"""Module docstring."""\n',
+    u'\uFEFF"""Module docstring."""\n',
 ])
 def test_strip_utf_bom(first_line):
     r"""Verify that we strip '\xEF\xBB\xBF' from the first line."""
     lines = [first_line]
-    file_checker = checker.FileChecker('stdin', [])
-    file_checker.lines = lines[:]
-    file_checker.strip_utf_bom()
-    assert file_checker.lines != lines
-    assert file_checker.lines[0] == '"""Module docstring."""\n'
+    file_processor = processor.FileProcessor('-', options_from(), lines[:])
+    assert file_processor.lines != lines
+    assert file_processor.lines[0] == '"""Module docstring."""\n'