283 lines
9.2 KiB
Python
283 lines
9.2 KiB
Python
|
# mako/pygen.py
|
||
|
|
# Copyright (C) 2006-2013 the Mako authors and contributors <see AUTHORS file>
|
||
|
|
#
|
||
|
|
# This module is part of Mako and is released under
|
||
|
|
# the MIT License: http://www.opensource.org/licenses/mit-license.php
|
||
|
|
|
||
|
|
"""utilities for generating and formatting literal Python code."""
|
||
|
|
|
||
|
|
import re
|
||
|
|
from mako import exceptions
|
||
|
|
|
||
|
|
class PythonPrinter(object):
|
||
|
|
def __init__(self, stream):
|
||
|
|
# indentation counter
|
||
|
|
self.indent = 0
|
||
|
|
|
||
|
|
# a stack storing information about why we incremented
|
||
|
|
# the indentation counter, to help us determine if we
|
||
|
|
# should decrement it
|
||
|
|
self.indent_detail = []
|
||
|
|
|
||
|
|
# the string of whitespace multiplied by the indent
|
||
|
|
# counter to produce a line
|
||
|
|
self.indentstring = " "
|
||
|
|
|
||
|
|
# the stream we are writing to
|
||
|
|
self.stream = stream
|
||
|
|
|
||
|
|
# a list of lines that represents a buffered "block" of code,
|
||
|
|
# which can be later printed relative to an indent level
|
||
|
|
self.line_buffer = []
|
||
|
|
|
||
|
|
self.in_indent_lines = False
|
||
|
|
|
||
|
|
self._reset_multi_line_flags()
|
||
|
|
|
||
|
|
def write(self, text):
|
||
|
|
self.stream.write(text)
|
||
|
|
|
||
|
|
def write_indented_block(self, block):
|
||
|
|
"""print a line or lines of python which already contain indentation.
|
||
|
|
|
||
|
|
The indentation of the total block of lines will be adjusted to that of
|
||
|
|
the current indent level."""
|
||
|
|
self.in_indent_lines = False
|
||
|
|
for l in re.split(r'\r?\n', block):
|
||
|
|
self.line_buffer.append(l)
|
||
|
|
|
||
|
|
def writelines(self, *lines):
|
||
|
|
"""print a series of lines of python."""
|
||
|
|
for line in lines:
|
||
|
|
self.writeline(line)
|
||
|
|
|
||
|
|
def writeline(self, line):
|
||
|
|
"""print a line of python, indenting it according to the current
|
||
|
|
indent level.
|
||
|
|
|
||
|
|
this also adjusts the indentation counter according to the
|
||
|
|
content of the line.
|
||
|
|
|
||
|
|
"""
|
||
|
|
|
||
|
|
if not self.in_indent_lines:
|
||
|
|
self._flush_adjusted_lines()
|
||
|
|
self.in_indent_lines = True
|
||
|
|
|
||
|
|
if (line is None or
|
||
|
|
re.match(r"^\s*#",line) or
|
||
|
|
re.match(r"^\s*$", line)
|
||
|
|
):
|
||
|
|
hastext = False
|
||
|
|
else:
|
||
|
|
hastext = True
|
||
|
|
|
||
|
|
is_comment = line and len(line) and line[0] == '#'
|
||
|
|
|
||
|
|
# see if this line should decrease the indentation level
|
||
|
|
if (not is_comment and
|
||
|
|
(not hastext or self._is_unindentor(line))
|
||
|
|
):
|
||
|
|
|
||
|
|
if self.indent > 0:
|
||
|
|
self.indent -=1
|
||
|
|
# if the indent_detail stack is empty, the user
|
||
|
|
# probably put extra closures - the resulting
|
||
|
|
# module wont compile.
|
||
|
|
if len(self.indent_detail) == 0:
|
||
|
|
raise exceptions.SyntaxException(
|
||
|
|
"Too many whitespace closures")
|
||
|
|
self.indent_detail.pop()
|
||
|
|
|
||
|
|
if line is None:
|
||
|
|
return
|
||
|
|
|
||
|
|
# write the line
|
||
|
|
self.stream.write(self._indent_line(line) + "\n")
|
||
|
|
|
||
|
|
# see if this line should increase the indentation level.
|
||
|
|
# note that a line can both decrase (before printing) and
|
||
|
|
# then increase (after printing) the indentation level.
|
||
|
|
|
||
|
|
if re.search(r":[ \t]*(?:#.*)?$", line):
|
||
|
|
# increment indentation count, and also
|
||
|
|
# keep track of what the keyword was that indented us,
|
||
|
|
# if it is a python compound statement keyword
|
||
|
|
# where we might have to look for an "unindent" keyword
|
||
|
|
match = re.match(r"^\s*(if|try|elif|while|for|with)", line)
|
||
|
|
if match:
|
||
|
|
# its a "compound" keyword, so we will check for "unindentors"
|
||
|
|
indentor = match.group(1)
|
||
|
|
self.indent +=1
|
||
|
|
self.indent_detail.append(indentor)
|
||
|
|
else:
|
||
|
|
indentor = None
|
||
|
|
# its not a "compound" keyword. but lets also
|
||
|
|
# test for valid Python keywords that might be indenting us,
|
||
|
|
# else assume its a non-indenting line
|
||
|
|
m2 = re.match(r"^\s*(def|class|else|elif|except|finally)",
|
||
|
|
line)
|
||
|
|
if m2:
|
||
|
|
self.indent += 1
|
||
|
|
self.indent_detail.append(indentor)
|
||
|
|
|
||
|
|
def close(self):
|
||
|
|
"""close this printer, flushing any remaining lines."""
|
||
|
|
self._flush_adjusted_lines()
|
||
|
|
|
||
|
|
def _is_unindentor(self, line):
|
||
|
|
"""return true if the given line is an 'unindentor',
|
||
|
|
relative to the last 'indent' event received.
|
||
|
|
|
||
|
|
"""
|
||
|
|
|
||
|
|
# no indentation detail has been pushed on; return False
|
||
|
|
if len(self.indent_detail) == 0:
|
||
|
|
return False
|
||
|
|
|
||
|
|
indentor = self.indent_detail[-1]
|
||
|
|
|
||
|
|
# the last indent keyword we grabbed is not a
|
||
|
|
# compound statement keyword; return False
|
||
|
|
if indentor is None:
|
||
|
|
return False
|
||
|
|
|
||
|
|
# if the current line doesnt have one of the "unindentor" keywords,
|
||
|
|
# return False
|
||
|
|
match = re.match(r"^\s*(else|elif|except|finally).*\:", line)
|
||
|
|
if not match:
|
||
|
|
return False
|
||
|
|
|
||
|
|
# whitespace matches up, we have a compound indentor,
|
||
|
|
# and this line has an unindentor, this
|
||
|
|
# is probably good enough
|
||
|
|
return True
|
||
|
|
|
||
|
|
# should we decide that its not good enough, heres
|
||
|
|
# more stuff to check.
|
||
|
|
#keyword = match.group(1)
|
||
|
|
|
||
|
|
# match the original indent keyword
|
||
|
|
#for crit in [
|
||
|
|
# (r'if|elif', r'else|elif'),
|
||
|
|
# (r'try', r'except|finally|else'),
|
||
|
|
# (r'while|for', r'else'),
|
||
|
|
#]:
|
||
|
|
# if re.match(crit[0], indentor) and re.match(crit[1], keyword):
|
||
|
|
# return True
|
||
|
|
|
||
|
|
#return False
|
||
|
|
|
||
|
|
def _indent_line(self, line, stripspace=''):
|
||
|
|
"""indent the given line according to the current indent level.
|
||
|
|
|
||
|
|
stripspace is a string of space that will be truncated from the
|
||
|
|
start of the line before indenting."""
|
||
|
|
|
||
|
|
return re.sub(r"^%s" % stripspace, self.indentstring
|
||
|
|
* self.indent, line)
|
||
|
|
|
||
|
|
def _reset_multi_line_flags(self):
|
||
|
|
"""reset the flags which would indicate we are in a backslashed
|
||
|
|
or triple-quoted section."""
|
||
|
|
|
||
|
|
self.backslashed, self.triplequoted = False, False
|
||
|
|
|
||
|
|
def _in_multi_line(self, line):
|
||
|
|
"""return true if the given line is part of a multi-line block,
|
||
|
|
via backslash or triple-quote."""
|
||
|
|
|
||
|
|
# we are only looking for explicitly joined lines here, not
|
||
|
|
# implicit ones (i.e. brackets, braces etc.). this is just to
|
||
|
|
# guard against the possibility of modifying the space inside of
|
||
|
|
# a literal multiline string with unfortunately placed
|
||
|
|
# whitespace
|
||
|
|
|
||
|
|
current_state = (self.backslashed or self.triplequoted)
|
||
|
|
|
||
|
|
if re.search(r"\\$", line):
|
||
|
|
self.backslashed = True
|
||
|
|
else:
|
||
|
|
self.backslashed = False
|
||
|
|
|
||
|
|
triples = len(re.findall(r"\"\"\"|\'\'\'", line))
|
||
|
|
if triples == 1 or triples % 2 != 0:
|
||
|
|
self.triplequoted = not self.triplequoted
|
||
|
|
|
||
|
|
return current_state
|
||
|
|
|
||
|
|
def _flush_adjusted_lines(self):
|
||
|
|
stripspace = None
|
||
|
|
self._reset_multi_line_flags()
|
||
|
|
|
||
|
|
for entry in self.line_buffer:
|
||
|
|
if self._in_multi_line(entry):
|
||
|
|
self.stream.write(entry + "\n")
|
||
|
|
else:
|
||
|
|
entry = entry.expandtabs()
|
||
|
|
if stripspace is None and re.search(r"^[ \t]*[^# \t]", entry):
|
||
|
|
stripspace = re.match(r"^([ \t]*)", entry).group(1)
|
||
|
|
self.stream.write(self._indent_line(entry, stripspace) + "\n")
|
||
|
|
|
||
|
|
self.line_buffer = []
|
||
|
|
self._reset_multi_line_flags()
|
||
|
|
|
||
|
|
|
||
|
|
def adjust_whitespace(text):
|
||
|
|
"""remove the left-whitespace margin of a block of Python code."""
|
||
|
|
|
||
|
|
state = [False, False]
|
||
|
|
(backslashed, triplequoted) = (0, 1)
|
||
|
|
|
||
|
|
def in_multi_line(line):
|
||
|
|
start_state = (state[backslashed] or state[triplequoted])
|
||
|
|
|
||
|
|
if re.search(r"\\$", line):
|
||
|
|
state[backslashed] = True
|
||
|
|
else:
|
||
|
|
state[backslashed] = False
|
||
|
|
|
||
|
|
def match(reg, t):
|
||
|
|
m = re.match(reg, t)
|
||
|
|
if m:
|
||
|
|
return m, t[len(m.group(0)):]
|
||
|
|
else:
|
||
|
|
return None, t
|
||
|
|
|
||
|
|
while line:
|
||
|
|
if state[triplequoted]:
|
||
|
|
m, line = match(r"%s" % state[triplequoted], line)
|
||
|
|
if m:
|
||
|
|
state[triplequoted] = False
|
||
|
|
else:
|
||
|
|
m, line = match(r".*?(?=%s|$)" % state[triplequoted], line)
|
||
|
|
else:
|
||
|
|
m, line = match(r'#', line)
|
||
|
|
if m:
|
||
|
|
return start_state
|
||
|
|
|
||
|
|
m, line = match(r"\"\"\"|\'\'\'", line)
|
||
|
|
if m:
|
||
|
|
state[triplequoted] = m.group(0)
|
||
|
|
continue
|
||
|
|
|
||
|
|
m, line = match(r".*?(?=\"\"\"|\'\'\'|#|$)", line)
|
||
|
|
|
||
|
|
return start_state
|
||
|
|
|
||
|
|
def _indent_line(line, stripspace = ''):
|
||
|
|
return re.sub(r"^%s" % stripspace, '', line)
|
||
|
|
|
||
|
|
lines = []
|
||
|
|
stripspace = None
|
||
|
|
|
||
|
|
for line in re.split(r'\r?\n', text):
|
||
|
|
if in_multi_line(line):
|
||
|
|
lines.append(line)
|
||
|
|
else:
|
||
|
|
line = line.expandtabs()
|
||
|
|
if stripspace is None and re.search(r"^[ \t]*[^# \t]", line):
|
||
|
|
stripspace = re.match(r"^([ \t]*)", line).group(1)
|
||
|
|
lines.append(_indent_line(line, stripspace))
|
||
|
|
return "\n".join(lines)
|