[
https://issues.apache.org/jira/browse/ARROW-2218?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16380849#comment-16380849
]
ASF GitHub Bot commented on ARROW-2218:
---------------------------------------
wesm closed pull request #1674: ARROW-2218: [Python] PythonFile should infer
mode when not given
URL: https://github.com/apache/arrow/pull/1674
This is a PR merged from a forked repository.
As GitHub hides the original diff on merge, it is displayed below for
the sake of provenance:
As this is a foreign pull request (from a fork), the diff is supplied
below (as it won't show otherwise due to GitHub magic):
diff --git a/python/pyarrow/io-hdfs.pxi b/python/pyarrow/io-hdfs.pxi
index dc6ba23ab..31c0437e4 100644
--- a/python/pyarrow/io-hdfs.pxi
+++ b/python/pyarrow/io-hdfs.pxi
@@ -480,7 +480,5 @@ cdef class HdfsFile(NativeFile):
object mode
object parent
- cdef object __weakref__
-
def __dealloc__(self):
self.parent = None
diff --git a/python/pyarrow/io.pxi b/python/pyarrow/io.pxi
index 8b364dc71..0b444cdb9 100644
--- a/python/pyarrow/io.pxi
+++ b/python/pyarrow/io.pxi
@@ -410,9 +410,21 @@ cdef class PythonFile(NativeFile):
cdef:
object handle
- def __cinit__(self, handle, mode='w'):
+ def __cinit__(self, handle, mode=None):
self.handle = handle
+ if mode is None:
+ try:
+ mode = handle.mode
+ except AttributeError:
+ # Not all file-like objects have a mode attribute
+ # (e.g. BytesIO)
+ try:
+ mode = 'w' if handle.writable() else 'r'
+ except AttributeError:
+ raise ValueError("could not infer open mode for file-like "
+ "object %r, please pass it explicitly"
+ % (handle,))
if mode.startswith('w'):
self.wr_file.reset(new PyOutputStream(handle))
self.is_writable = True
diff --git a/python/pyarrow/lib.pxd b/python/pyarrow/lib.pxd
index 31732a6e0..e4d574f18 100644
--- a/python/pyarrow/lib.pxd
+++ b/python/pyarrow/lib.pxd
@@ -337,6 +337,7 @@ cdef class NativeFile:
bint is_writable
readonly bint closed
bint own_file
+ object __weakref__
# By implementing these "virtual" functions (all functions in Cython
# extension classes are technically virtual in the C++ sense) we can expose
diff --git a/python/pyarrow/tests/test_io.py b/python/pyarrow/tests/test_io.py
index 736020f60..d269ad0e7 100644
--- a/python/pyarrow/tests/test_io.py
+++ b/python/pyarrow/tests/test_io.py
@@ -21,6 +21,7 @@
import os
import pytest
import sys
+import weakref
import numpy as np
@@ -124,6 +125,44 @@ def get_buffer():
assert buf.to_pybytes() == b'sample'
assert buf.parent is not None
+
+def test_python_file_implicit_mode(tmpdir):
+ path = os.path.join(str(tmpdir), 'foo.txt')
+ with open(path, 'wb') as f:
+ pf = pa.PythonFile(f)
+ assert pf.writable()
+ assert not pf.readable()
+ assert not pf.seekable() # PyOutputStream isn't seekable
+ f.write(b'foobar\n')
+
+ with open(path, 'rb') as f:
+ pf = pa.PythonFile(f)
+ assert pf.readable()
+ assert not pf.writable()
+ assert pf.seekable()
+ assert pf.read() == b'foobar\n'
+
+ bio = BytesIO()
+ pf = pa.PythonFile(bio)
+ assert pf.writable()
+ assert not pf.readable()
+ assert not pf.seekable()
+ pf.write(b'foobar\n')
+ assert bio.getvalue() == b'foobar\n'
+
+
+def test_python_file_closing():
+ bio = BytesIO()
+ pf = pa.PythonFile(bio)
+ wr = weakref.ref(pf)
+ del pf
+ assert wr() is None # object was destroyed
+ assert not bio.closed
+ pf = pa.PythonFile(bio)
+ pf.close()
+ assert bio.closed
+
+
# ----------------------------------------------------------------------
# Buffers
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org
> [Python] PythonFile should infer mode when not given
> ----------------------------------------------------
>
> Key: ARROW-2218
> URL: https://issues.apache.org/jira/browse/ARROW-2218
> Project: Apache Arrow
> Issue Type: Improvement
> Components: Python
> Affects Versions: 0.8.0
> Reporter: Antoine Pitrou
> Assignee: Antoine Pitrou
> Priority: Minor
> Labels: pull-request-available
> Fix For: 0.9.0
>
>
> The following is clearly not optimal:
> {code:python}
> >>> f = open('README.md', 'r')
> >>> pa.PythonFile(f).mode
> 'wb'
> {code}
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
