Vendor shutil.get_terminal_size.

Use the vendored version only if import error.
That should fix import error for many users.

Closes  #9815.

This is only against the 5.x branch as this is in the stdlib on Python 3

IPython/utils/_get_terminal_size.py

@@ -0,0 +1,103 b''
+# vendored version of backports.get_terminal_size as nemesapece package are a
+# mess and break, especially on ubuntu. This file is under MIT Licence. 
+# See https://pypi.python.org/pypi/backports.shutil_get_terminal_size
+"""This is a backport of shutil.get_terminal_size from Python 3.3.
+
+The original implementation is in C, but here we use the ctypes and
+fcntl modules to create a pure Python version of os.get_terminal_size.
+"""
+
+import os
+import struct
+import sys
+
+from collections import namedtuple
+
+__all__ = ["get_terminal_size"]
+
+
+terminal_size = namedtuple("terminal_size", "columns lines")
+
+try:
+    from ctypes import windll, create_string_buffer
+
+    _handles = {
+        0: windll.kernel32.GetStdHandle(-10),
+        1: windll.kernel32.GetStdHandle(-11),
+        2: windll.kernel32.GetStdHandle(-12),
+    }
+
+    def _get_terminal_size(fd):
+        columns = lines = 0
+
+        try:
+            handle = _handles[fd]
+            csbi = create_string_buffer(22)
+            res = windll.kernel32.GetConsoleScreenBufferInfo(handle, csbi)
+            if res:
+                res = struct.unpack("hhhhHhhhhhh", csbi.raw)
+                left, top, right, bottom = res[5:9]
+                columns = right - left + 1
+                lines = bottom - top + 1
+        except Exception:
+            pass
+
+        return terminal_size(columns, lines)
+
+except ImportError:
+    import fcntl
+    import termios
+
+    def _get_terminal_size(fd):
+        try:
+            res = fcntl.ioctl(fd, termios.TIOCGWINSZ, b"\x00" * 4)
+            lines, columns = struct.unpack("hh", res)
+        except Exception:
+            columns = lines = 0
+
+        return terminal_size(columns, lines)
+
+
+def get_terminal_size(fallback=(80, 24)):
+    """Get the size of the terminal window.
+
+    For each of the two dimensions, the environment variable, COLUMNS
+    and LINES respectively, is checked. If the variable is defined and
+    the value is a positive integer, it is used.
+
+    When COLUMNS or LINES is not defined, which is the common case,
+    the terminal connected to sys.__stdout__ is queried
+    by invoking os.get_terminal_size.
+
+    If the terminal size cannot be successfully queried, either because
+    the system doesn't support querying, or because we are not
+    connected to a terminal, the value given in fallback parameter
+    is used. Fallback defaults to (80, 24) which is the default
+    size used by many terminal emulators.
+
+    The value returned is a named tuple of type os.terminal_size.
+    """
+    # Try the environment first
+    try:
+        columns = int(os.environ["COLUMNS"])
+    except (KeyError, ValueError):
+        columns = 0
+
+    try:
+        lines = int(os.environ["LINES"])
+    except (KeyError, ValueError):
+        lines = 0
+
+    # Only query if necessary
+    if columns <= 0 or lines <= 0:
+        try:
+            size = _get_terminal_size(sys.__stdout__.fileno())
+        except (NameError, OSError):
+            size = terminal_size(*fallback)
+
+        if columns <= 0:
+            columns = size.columns
+        if lines <= 0:
+            lines = size.lines
+
+    return terminal_size(columns, lines)

IPython/utils/terminal.py

@@ -9,6 +9,8 b' Authors:'
 * Alexander Belchenko (e-mail: bialix AT ukr.net)
 """
 
+from __future__ import absolute_import
+
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
@@ -19,7 +21,10 b' try:'
     from shutil import get_terminal_size as _get_terminal_size
 except ImportError:
     # use backport on Python 2
+    try:
     from backports.shutil_get_terminal_size import get_terminal_size as _get_terminal_size
+    except ImportError:
+        from ._get_terminal_size import _get_terminal_size
 
 from . import py3compat