Source code for interact.pretty
# Copyright (c) 2013 Galah Group LLC
# Copyright (c) 2013 Other contributers as noted in the CONTRIBUTERS file
#
# This file is part of galah-interact-python.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
#
# You may obtain a copy of the License at
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""
Module useful for displaying nice, grammatically correct output.
"""
[docs]def pretty_list(the_list, conjunction = "and", none_string = "nothing"):
"""
Returns a grammatically correct string representing the given list. For
example...
>>> pretty_list(["John", "Bill", "Stacy"])
"John, Bill, and Stacy"
>>> pretty_list(["Bill", "Jorgan"], "or")
"Bill or Jorgan"
>>> pretty_list([], none_string = "nobody")
"nobody"
"""
the_list = list(the_list)
if len(the_list) == 0:
return none_string
elif len(the_list) == 1:
return str(the_list[0])
elif len(the_list) == 2:
return str(the_list[0]) + " " + conjunction + " " + str(the_list[1])
else:
# Add every item except the last two together seperated by commas
result = ", ".join([str(s) for s in the_list[:-2]]) + ", "
# Add the last two items, joined together by a command and the given
# conjunction
result += "%s, %s %s" % \
(str(the_list[-2]), conjunction, str(the_list[-1]))
return result
[docs]def plural_if(zstring, zcondition):
"""
Returns zstring pluralized (adds an 's' to the end) if zcondition is True or
if zcondition is not equal to 1.
Example usage could be ``plural_if("cow", len(cow_list))``.
"""
# If they gave us a boolean value, just use that, otherwise, assume the
# value is some integral type.
if type(zcondition) is bool:
plural = zcondition
else:
plural = zcondition != 1
return zstring + ("s" if plural else "")
def limit_string_length(string, max_lines = 20, max_characters = 20 * 72):
# If the string is empty, we don't need to do anything.
# if not string:
# return string
# Negative values are bad
if max_lines < 0:
raise TypeError("max_lines cannot be negative, got %d." % (max_lines, ))
elif max_characters < 0:
raise TypeError(
"max_characters cannot be negative, got %d." % (max_lines, )
)
nlines_truncated = 0
lines = string.splitlines()
if len(lines) > max_lines:
nlines_truncated = len(lines) - max_lines
lines = lines[:max_lines]
ncharacters_truncated = 0
if len(string) > max_characters:
ncharacters_truncated = len(string) - max_characters
string = string[:max_characters]
return (string, nlines_truncated, ncharacters_truncated)
def truncate_string(string, max_lines = 20, max_characters = 20 * 72):
new_string, nlines_truncated, ncharacters_truncated = limit_string_length(
string, max_lines, max_characters
)
if ncharacters_truncated == 0 and nlines_truncated == 0:
return new_string
else:
return new_string + "\n---Remaining text truncated---"
[docs]def craft_shell_command(command):
"""
Returns a shell command from a list of arguments suitable to be passed into
subprocess.Popen. The returned string should only be used for display
purposes and is not secure enough to actually be sent into a shell.
"""
return " ".join([escape_shell_string(i) for i in command])
[docs]def escape_shell_string(str):
"""
Escapes a shell string such that it is suitable to be displayed to the user.
This function **should not** be used to actually feed arguments into a shell
as this function **is not** secure enough.
"""
escaped = str.replace("\\", "\\\\").replace("\"", "\\\"")
if " " in escaped:
escaped = "\"" + escaped + "\""
return escaped