Merge pull request #2405 from oesteban/enh/add-hashfile-tests

[ENH] Add tests to ``hash_files``

Author: oesteban

nipype/utils/filemanip.py

@@ -3,6 +3,13 @@
 # vi: set ft=python sts=4 ts=4 sw=4 et:
 """Miscellaneous file manipulation functions
 
+  .. testsetup::
+    # Change directory to provide relative paths for doctests
+    >>> import os
+    >>> filepath = os.path.dirname(os.path.realpath( __file__ ))
+    >>> datadir = os.path.realpath(os.path.join(filepath, '../testing/data'))
+    >>> os.chdir(datadir)
+
 """
 from __future__ import (print_function, division, unicode_literals,
                         absolute_import)
@@ -222,19 +229,38 @@ def check_forhash(filename):
         return False, None
 
 
-def hash_infile(afile, chunk_len=8192, crypto=hashlib.md5):
-    """ Computes hash of a file using 'crypto' module"""
-    hex = None
-    if op.isfile(afile):
-        crypto_obj = crypto()
-        with open(afile, 'rb') as fp:
-            while True:
-                data = fp.read(chunk_len)
-                if not data:
-                    break
-                crypto_obj.update(data)
-        hex = crypto_obj.hexdigest()
-    return hex
+def hash_infile(afile, chunk_len=8192, crypto=hashlib.md5,
+                raise_notfound=False):
+    """
+    Computes hash of a file using 'crypto' module
+
+    >>> hash_infile('smri_ants_registration_settings.json')
+    '49b956387ed8d95a4eb44576fc5103b6'
+
+    >>> hash_infile('surf01.vtk')
+    'fdf1cf359b4e346034372cdeb58f9a88'
+
+    >>> hash_infile('spminfo')
+    '0dc55e3888c98a182dab179b976dfffc'
+
+    >>> hash_infile('fsl_motion_outliers_fd.txt')
+    'defd1812c22405b1ee4431aac5bbdd73'
+
+
+    """
+    if not op.isfile(afile):
+        if raise_notfound:
+            raise RuntimeError('File "%s" not found.' % afile)
+        return None
+
+    crypto_obj = crypto()
+    with open(afile, 'rb') as fp:
+        while True:
+            data = fp.read(chunk_len)
+            if not data:
+                break
+            crypto_obj.update(data)
+    return crypto_obj.hexdigest()
 
 
 def hash_timestamp(afile):