RF: Drop python < 3.5.1 hacks in openers

Author: effigies

nibabel/openers.py

@@ -10,10 +10,7 @@
 """
 
 import sys
-if sys.version_info[0] < 3:
-    from bz2file import BZ2File
-else:
-    from bz2 import BZ2File
+from bz2 import BZ2File
 import gzip
 import sys
 import warnings
@@ -43,51 +40,6 @@
     HAVE_INDEXED_GZIP = False
 
 
-# The largest memory chunk that gzip can use for reads
-GZIP_MAX_READ_CHUNK = 100 * 1024 * 1024  # 100Mb
-
-
-class BufferedGzipFile(gzip.GzipFile):
-    """GzipFile able to readinto buffer >= 2**32 bytes.
-
-    This class only differs from gzip.GzipFile
-    in Python 3.5.0.
-
-    This works around a known issue in Python 3.5.
-    See https://bugs.python.org/issue25626
-    """
-
-    # This helps avoid defining readinto in Python 2.6,
-    #   where it is undefined on gzip.GzipFile.
-    # It also helps limit the exposure to this code.
-    if sys.version_info[:3] == (3, 5, 0):
-        def __init__(self, fileish, mode='rb', compresslevel=9,
-                     buffer_size=2**32 - 1):
-            super(BufferedGzipFile, self).__init__(fileish, mode=mode,
-                                                   compresslevel=compresslevel)
-            self.buffer_size = buffer_size
-
-        def readinto(self, buf):
-            """Uses self.buffer_size to do a buffered read."""
-            n_bytes = len(buf)
-            if n_bytes < 2 ** 32:
-                return super(BufferedGzipFile, self).readinto(buf)
-
-            # This works around a known issue in Python 3.5.
-            # See https://bugs.python.org/issue25626
-            mv = memoryview(buf)
-            n_read = 0
-            max_read = 2 ** 32 - 1  # Max for unsigned 32-bit integer
-            while (n_read < n_bytes):
-                n_wanted = min(n_bytes - n_read, max_read)
-                n_got = super(BufferedGzipFile, self).readinto(
-                    mv[n_read:n_read + n_wanted])
-                n_read += n_got
-                if n_got != n_wanted:
-                    break
-            return n_read
-
-
 def _gzip_open(filename, mode='rb', compresslevel=9, keep_open=False):
 
     # use indexed_gzip if possible for faster read access.  If keep_open ==
@@ -96,16 +48,9 @@ def _gzip_open(filename, mode='rb', compresslevel=9, keep_open=False):
     if HAVE_INDEXED_GZIP and mode == 'rb':
         gzip_file = IndexedGzipFile(filename, drop_handles=not keep_open)
 
-    # Fall-back to built-in GzipFile (wrapped with the BufferedGzipFile class
-    # defined above)
+    # Fall-back to built-in GzipFile
     else:
-        gzip_file = BufferedGzipFile(filename, mode, compresslevel)
-
-    # Speedup for #209, for versions of python < 3.5. Open gzip files with
-    # faster reads on large files using a larger read buffer. See
-    # https://github.com/nipy/nibabel/pull/210 for discussion
-    if hasattr(gzip_file, 'max_read_chunk'):
-        gzip_file.max_read_chunk = GZIP_MAX_READ_CHUNK
+        gzip_file = gzip.GzipFile(filename, mode, compresslevel)
 
     return gzip_file
 

setup.cfg

@@ -13,8 +13,6 @@ classifiers =
     License :: OSI Approved :: MIT License
     Operating System :: OS Independent
     Programming Language :: Python
-    Programming Language :: Python :: 2.7
-    Programming Language :: Python :: 3.4
     Programming Language :: Python :: 3.5
     Programming Language :: Python :: 3.6
     Programming Language :: Python :: 3.7
@@ -29,7 +27,7 @@ provides =
     nisext
 
 [options]
-python_requires = >=3.5
+python_requires = >=3.5.1
 install_requires =
     numpy >=1.12
 tests_require =