fix issue leonidessaguisagjr#10: Evaluate file paths from checksum dir

filehash/filehash.py

@@ -1,5 +1,6 @@
 import abc
 import collections
+from contextlib import contextmanager
 import glob
 import hashlib
 import os
@@ -261,7 +262,8 @@ def verify_checksums(self, checksum_filename):
                   there was a checksum mismatch (False).
         """
         result = []
-        with open(checksum_filename, mode="r") as checksum_list:
+        checksum_dir = os.path.dirname(os.path.realpath(checksum_filename))
+        with open(checksum_filename, mode="r") as checksum_list, _chdir(checksum_dir):
             for line in checksum_list:
                 expected_hash, filename = line.strip().split(" ", 1)
                 filename = filename.strip()
@@ -296,7 +298,8 @@ def verify_sfv(self, sfv_filename):
         if self.hash_algorithm.lower() != 'crc32':
             raise TypeError("SFV verification only supported with the 'crc32' algorithm.")
         result = []
-        with open(sfv_filename, mode="r") as checksum_list:
+        checksum_dir = os.path.dirname(os.path.realpath(sfv_filename))
+        with open(sfv_filename, mode="r") as checksum_list, _chdir(checksum_dir):
             for line in checksum_list:
                 if line.startswith(";"):
                     continue
@@ -305,6 +308,16 @@ def verify_sfv(self, sfv_filename):
                 result.append(VerifyHashResult(filename, expected_crc32 == actual_crc32))
         return result
 
+@contextmanager
+def _chdir(dir_path):
+    _original = os.getcwd()
+    os.chdir(dir_path)
+    try:
+        yield
+    except:
+        raise Exception('unable to change to hash directory')
+    finally:
+        os.chdir(_original)
 
 _ALGORITHM_MAP = {
     'adler32': Adler32,

test_filehash.py

@@ -1,12 +1,18 @@
 import inspect
+import logging
 import os.path
+import sys
 import unittest
 
 import filehash.filehash
 from filehash import FileHash, SUPPORTED_ALGORITHMS
 
 from filehash.filehash_cli import create_parser
 
+logging.basicConfig(stream=sys.stderr)
+logging.getLogger().setLevel(logging.DEBUG)
+
+logger = logging.getLogger(__file__)
 
 class TestFileHash(unittest.TestCase):
     """Test the FileHash class."""
@@ -64,7 +70,8 @@ def setUp(self):
             }
         }
         self.current_dir = os.getcwd()
-        os.chdir(os.path.join(os.path.abspath(os.path.dirname(__file__)), "testdata"))
+        self.testdata_dir = os.path.join(os.path.abspath(os.path.dirname(__file__)), "testdata")
+        os.chdir(self.testdata_dir)
 
     def tearDown(self):
         os.chdir(self.current_dir)
@@ -186,6 +193,16 @@ def test_verify_checksums(self):
             results = [result.hashes_match for result in hasher.verify_checksums("hashes." + algo)]
             self.assertTrue(all(results))
 
+    def test_verify_checksums_from_outside_dir(self):
+        """Test the verify_checksums() method from outside the hash directory."""
+        os.chdir('/') # Change out of the "testdata" directory
+        logger.debug('Current directory: %s', os.path.realpath(os.curdir))
+        for algo in SUPPORTED_ALGORITHMS:
+            checksum_file = os.path.join(self.testdata_dir, "hashes." + algo)
+            hasher = FileHash(algo)
+            results = [result.hashes_match for result in hasher.verify_checksums(checksum_file)]
+            self.assertTrue(all(results))
+
     def test_verify_sfv(self):
         """Test the verify_sfv() method."""
         hasher = FileHash('crc32')
@@ -197,6 +214,14 @@ def test_verify_sfv_neg(self):
         hasher = FileHash('sha1')
         self.assertRaises(TypeError, hasher.verify_sfv, "lorem_ipsum.sfv")
 
+    def test_verify_sfv_outside_dir(self):
+        """Test the verify_sfv() method."""
+        os.chdir('/') # Change out of the "testdata" directory
+        checksum_file = os.path.join(self.testdata_dir, "lorem_ipsum.sfv")
+        hasher = FileHash('crc32')
+        results = [result.hashes_match for result in hasher.verify_sfv(checksum_file)]
+        self.assertTrue(all(results))
+
 
 class TestZlibHasherSubclasses(unittest.TestCase):
     """Test the subclasses of ZlibHasherBase i.e. Adler32, CRC32."""