# Copyright 2013-2018 Lawrence Livermore National Security, LLC and other
# Spack Project Developers. See the top-level COPYRIGHT file for details.
#
# SPDX-License-Identifier: (Apache-2.0 OR MIT)
"""
Routines for printing columnar output. See ``colify()`` for more information.
"""
from __future__ import division
import os
import sys
from six import StringIO
from llnl.util.tty import terminal_size
from llnl.util.tty.color import clen, cextra
class ColumnConfig:
def __init__(self, cols):
self.cols = cols
self.line_length = 0
self.valid = True
self.widths = [0] * cols # does not include ansi colors
def __repr__(self):
attrs = [(a, getattr(self, a))
for a in dir(self) if not a.startswith("__")]
return "<Config: %s>" % ", ".join("%s: %r" % a for a in attrs)
def config_variable_cols(elts, console_width, padding, cols=0):
"""Variable-width column fitting algorithm.
This function determines the most columns that can fit in the
screen width. Unlike uniform fitting, where all columns take
the width of the longest element in the list, each column takes
the width of its own longest element. This packs elements more
efficiently on screen.
If cols is nonzero, force
"""
if cols < 0:
raise ValueError("cols must be non-negative.")
# Get a bound on the most columns we could possibly have.
# 'clen' ignores length of ansi color sequences.
lengths = [clen(e) for e in elts]
max_cols = max(1, console_width // (min(lengths) + padding))
max_cols = min(len(elts), max_cols)
# Range of column counts to try. If forced, use the supplied value.
col_range = [cols] if cols else range(1, max_cols + 1)
# Determine the most columns possible for the console width.
configs = [ColumnConfig(c) for c in col_range]
for i, length in enumerate(lengths):
for conf in configs:
if conf.valid:
col = i // ((len(elts) + conf.cols - 1) // conf.cols)
p = padding if col < (conf.cols - 1) else 0
if conf.widths[col] < (length + p):
conf.line_length += length + p - conf.widths[col]
conf.widths[col] = length + p
conf.valid = (conf.line_length < console_width)
try:
config = next(conf for conf in reversed(configs) if conf.valid)
except StopIteration:
# If nothing was valid the screen was too narrow -- just use 1 col.
config = configs[0]
config.widths = [w for w in config.widths if w != 0]
config.cols = len(config.widths)
return config
def config_uniform_cols(elts, console_width, padding, cols=0):
"""Uniform-width column fitting algorithm.
Determines the longest element in the list, and determines how
many columns of that width will fit on screen. Returns a
corresponding column config.
"""
if cols < 0:
raise ValueError("cols must be non-negative.")
# 'clen' ignores length of ansi color sequences.
max_len = max(clen(e) for e in elts) + padding
if cols == 0:
cols = max(1, console_width // max_len)
cols = min(len(elts), cols)
config = ColumnConfig(cols)
config.widths = [max_len] * cols
return config
def colify(elts, **options):
"""Takes a list of elements as input and finds a good columnization
of them, similar to how gnu ls does. This supports both
uniform-width and variable-width (tighter) columns.
If elts is not a list of strings, each element is first conveted
using ``str()``.
Keyword Arguments:
output (stream): A file object to write to. Default is ``sys.stdout``
indent (int): Optionally indent all columns by some number of spaces
padding (int): Spaces between columns. Default is 2
width (int): Width of the output. Default is 80 if tty not detected
cols (int): Force number of columns. Default is to size to
terminal, or single-column if no tty
tty (bool): Whether to attempt to write to a tty. Default is to
autodetect a tty. Set to False to force single-column
output
method (str): Method to use to fit columns. Options are variable or
uniform. Variable-width columns are tighter, uniform
columns are all the same width and fit less data on
the screen
"""
# Get keyword arguments or set defaults
cols = options.pop("cols", 0)
output = options.pop("output", sys.stdout)
indent = options.pop("indent", 0)
padding = options.pop("padding", 2)
tty = options.pop('tty', None)
method = options.pop("method", "variable")
console_cols = options.pop("width", None)
if options:
raise TypeError(
"'%s' is an invalid keyword argument for this function."
% next(options.iterkeys()))
# elts needs to be an array of strings so we can count the elements
elts = [str(elt) for elt in elts]
if not elts:
return (0, ())
# environment size is of the form "<rows>x<cols>"
env_size = os.environ.get('COLIFY_SIZE')
if env_size:
try:
r, c = env_size.split('x')
console_rows, console_cols = int(r), int(c)
tty = True
except BaseException:
pass
# Use only one column if not a tty.
if not tty:
if tty is False or not output.isatty():
cols = 1
# Specify the number of character columns to use.
if not console_cols:
console_rows, console_cols = terminal_size()
elif type(console_cols) != int:
raise ValueError("Number of columns must be an int")
console_cols = max(1, console_cols - indent)
# Choose a method. Variable-width colums vs uniform-width.
if method == "variable":
config = config_variable_cols(elts, console_cols, padding, cols)
elif method == "uniform":
config = config_uniform_cols(elts, console_cols, padding, cols)
else:
raise ValueError("method must be either 'variable' or 'uniform'")
cols = config.cols
rows = (len(elts) + cols - 1) // cols
rows_last_col = len(elts) % rows
for row in range(rows):
output.write(" " * indent)
for col in range(cols):
elt = col * rows + row
width = config.widths[col] + cextra(elts[elt])
if col < cols - 1:
fmt = '%%-%ds' % width
output.write(fmt % elts[elt])
else:
# Don't pad the rightmost column (sapces can wrap on
# small teriminals if one line is overlong)
output.write(elts[elt])
output.write("\n")
row += 1
if row == rows_last_col:
cols -= 1
return (config.cols, tuple(config.widths))
def colify_table(table, **options):
"""Version of ``colify()`` for data expressed in rows, (list of lists).
Same as regular colify but takes a list of lists, where each
sub-list must be the same length, and each is interpreted as a
row in a table. Regular colify displays a sequential list of
values in columns.
"""
if table is None:
raise TypeError("Can't call colify_table on NoneType")
elif not table or not table[0]:
raise ValueError("Table is empty in colify_table!")
columns = len(table[0])
def transpose():
for i in range(columns):
for row in table:
yield row[i]
if 'cols' in options:
raise ValueError("Cannot override columsn in colify_table.")
options['cols'] = columns
colify(transpose(), **options)
def colified(elts, **options):
"""Invokes the ``colify()`` function but returns the result as a string
instead of writing it to an output string."""
sio = StringIO()
options['output'] = sio
colify(elts, **options)
return sio.getvalue()