cpython/Lib/formatter.py

403 lines
13 KiB
Python

import string
import sys
from types import StringType
AS_IS = None
class NullFormatter:
def __init__(self, writer=None):
if not writer:
writer = NullWriter()
self.writer = writer
def end_paragraph(self, blankline): pass
def add_line_break(self): pass
def add_hor_rule(self, *args, **kw): pass
def add_label_data(self, format, counter, blankline=None): pass
def add_flowing_data(self, data): pass
def add_literal_data(self, data): pass
def flush_softspace(self): pass
def push_alignment(self, align): pass
def pop_alignment(self): pass
def push_font(self, x): pass
def pop_font(self): pass
def push_margin(self, margin): pass
def pop_margin(self): pass
def set_spacing(self, spacing): pass
def push_style(self, *styles): pass
def pop_style(self, n=1): pass
def assert_line_data(self, flag=1): pass
class AbstractFormatter:
# Space handling policy: blank spaces at the boundary between elements
# are handled by the outermost context. "Literal" data is not checked
# to determine context, so spaces in literal data are handled directly
# in all circumstances.
def __init__(self, writer):
self.writer = writer # Output device
self.align = None # Current alignment
self.align_stack = [] # Alignment stack
self.font_stack = [] # Font state
self.margin_stack = [] # Margin state
self.spacing = None # Vertical spacing state
self.style_stack = [] # Other state, e.g. color
self.nospace = 1 # Should leading space be suppressed
self.softspace = 0 # Should a space be inserted
self.para_end = 1 # Just ended a paragraph
self.parskip = 0 # Skipped space between paragraphs?
self.hard_break = 1 # Have a hard break
self.have_label = 0
def end_paragraph(self, blankline):
if not self.hard_break:
self.writer.send_line_break()
self.have_label = 0
if self.parskip < blankline and not self.have_label:
self.writer.send_paragraph(blankline - self.parskip)
self.parskip = blankline
self.have_label = 0
self.hard_break = self.nospace = self.para_end = 1
self.softspace = 0
def add_line_break(self):
if not (self.hard_break or self.para_end):
self.writer.send_line_break()
self.have_label = self.parskip = 0
self.hard_break = self.nospace = 1
self.softspace = 0
def add_hor_rule(self, *args, **kw):
if not self.hard_break:
self.writer.send_line_break()
apply(self.writer.send_hor_rule, args, kw)
self.hard_break = self.nospace = 1
self.have_label = self.para_end = self.softspace = self.parskip = 0
def add_label_data(self, format, counter, blankline = None):
if self.have_label or not self.hard_break:
self.writer.send_line_break()
if not self.para_end:
self.writer.send_paragraph((blankline and 1) or 0)
if type(format) is StringType:
self.writer.send_label_data(self.format_counter(format, counter))
else:
self.writer.send_label_data(format)
self.nospace = self.have_label = self.hard_break = self.para_end = 1
self.softspace = self.parskip = 0
def format_counter(self, format, counter):
label = ''
for c in format:
try:
if c == '1':
label = label + ('%d' % counter)
elif c in 'aA':
if counter > 0:
label = label + self.format_letter(c, counter)
elif c in 'iI':
if counter > 0:
label = label + self.format_roman(c, counter)
else:
label = label + c
except:
label = label + c
return label
def format_letter(self, case, counter):
label = ''
while counter > 0:
counter, x = divmod(counter-1, 26)
s = chr(ord(case) + x)
label = s + label
return label
def format_roman(self, case, counter):
ones = ['i', 'x', 'c', 'm']
fives = ['v', 'l', 'd']
label, index = '', 0
# This will die of IndexError when counter is too big
while counter > 0:
counter, x = divmod(counter, 10)
if x == 9:
label = ones[index] + ones[index+1] + label
elif x == 4:
label = ones[index] + fives[index] + label
else:
if x >= 5:
s = fives[index]
x = x-5
else:
s = ''
s = s + ones[index]*x
label = s + label
index = index + 1
if case == 'I':
return string.upper(label)
return label
def add_flowing_data(self, data,
# These are only here to load them into locals:
whitespace = string.whitespace,
join = string.join, split = string.split):
if not data: return
# The following looks a bit convoluted but is a great improvement over
# data = regsub.gsub('[' + string.whitespace + ']+', ' ', data)
prespace = data[:1] in whitespace
postspace = data[-1:] in whitespace
data = join(split(data))
if self.nospace and not data:
return
elif prespace or self.softspace:
if not data:
if not self.nospace:
self.softspace = 1
self.parskip = 0
return
if not self.nospace:
data = ' ' + data
self.hard_break = self.nospace = self.para_end = \
self.parskip = self.have_label = 0
self.softspace = postspace
self.writer.send_flowing_data(data)
def add_literal_data(self, data):
if not data: return
if self.softspace:
self.writer.send_flowing_data(" ")
self.hard_break = data[-1:] == '\n'
self.nospace = self.para_end = self.softspace = \
self.parskip = self.have_label = 0
self.writer.send_literal_data(data)
def flush_softspace(self):
if self.softspace:
self.hard_break = self.para_end = self.parskip = \
self.have_label = self.softspace = 0
self.nospace = 1
self.writer.send_flowing_data(' ')
def push_alignment(self, align):
if align and align != self.align:
self.writer.new_alignment(align)
self.align = align
self.align_stack.append(align)
else:
self.align_stack.append(self.align)
def pop_alignment(self):
if self.align_stack:
del self.align_stack[-1]
if self.align_stack:
self.align = align = self.align_stack[-1]
self.writer.new_alignment(align)
else:
self.align = None
self.writer.new_alignment(None)
def push_font(self, (size, i, b, tt)):
if self.softspace:
self.hard_break = self.para_end = self.softspace = 0
self.nospace = 1
self.writer.send_flowing_data(' ')
if self.font_stack:
csize, ci, cb, ctt = self.font_stack[-1]
if size is AS_IS: size = csize
if i is AS_IS: i = ci
if b is AS_IS: b = cb
if tt is AS_IS: tt = ctt
font = (size, i, b, tt)
self.font_stack.append(font)
self.writer.new_font(font)
def pop_font(self):
if self.font_stack:
del self.font_stack[-1]
if self.font_stack:
font = self.font_stack[-1]
else:
font = None
self.writer.new_font(font)
def push_margin(self, margin):
self.margin_stack.append(margin)
fstack = filter(None, self.margin_stack)
if not margin and fstack:
margin = fstack[-1]
self.writer.new_margin(margin, len(fstack))
def pop_margin(self):
if self.margin_stack:
del self.margin_stack[-1]
fstack = filter(None, self.margin_stack)
if fstack:
margin = fstack[-1]
else:
margin = None
self.writer.new_margin(margin, len(fstack))
def set_spacing(self, spacing):
self.spacing = spacing
self.writer.new_spacing(spacing)
def push_style(self, *styles):
if self.softspace:
self.hard_break = self.para_end = self.softspace = 0
self.nospace = 1
self.writer.send_flowing_data(' ')
for style in styles:
self.style_stack.append(style)
self.writer.new_styles(tuple(self.style_stack))
def pop_style(self, n=1):
del self.style_stack[-n:]
self.writer.new_styles(tuple(self.style_stack))
def assert_line_data(self, flag=1):
self.nospace = self.hard_break = not flag
self.para_end = self.parskip = self.have_label = 0
class NullWriter:
"""Minimal writer interface to use in testing & inheritance."""
def __init__(self): pass
def flush(self): pass
def new_alignment(self, align): pass
def new_font(self, font): pass
def new_margin(self, margin, level): pass
def new_spacing(self, spacing): pass
def new_styles(self, styles): pass
def send_paragraph(self, blankline): pass
def send_line_break(self): pass
def send_hor_rule(self, *args, **kw): pass
def send_label_data(self, data): pass
def send_flowing_data(self, data): pass
def send_literal_data(self, data): pass
class AbstractWriter(NullWriter):
def __init__(self):
pass
def new_alignment(self, align):
print "new_alignment(%s)" % `align`
def new_font(self, font):
print "new_font(%s)" % `font`
def new_margin(self, margin, level):
print "new_margin(%s, %d)" % (`margin`, level)
def new_spacing(self, spacing):
print "new_spacing(%s)" % `spacing`
def new_styles(self, styles):
print "new_styles(%s)" % `styles`
def send_paragraph(self, blankline):
print "send_paragraph(%s)" % `blankline`
def send_line_break(self):
print "send_line_break()"
def send_hor_rule(self, *args, **kw):
print "send_hor_rule()"
def send_label_data(self, data):
print "send_label_data(%s)" % `data`
def send_flowing_data(self, data):
print "send_flowing_data(%s)" % `data`
def send_literal_data(self, data):
print "send_literal_data(%s)" % `data`
class DumbWriter(NullWriter):
def __init__(self, file=None, maxcol=72):
self.file = file or sys.stdout
self.maxcol = maxcol
NullWriter.__init__(self)
self.reset()
def reset(self):
self.col = 0
self.atbreak = 0
def send_paragraph(self, blankline):
self.file.write('\n' + '\n'*blankline)
self.col = 0
self.atbreak = 0
def send_line_break(self):
self.file.write('\n')
self.col = 0
self.atbreak = 0
def send_hor_rule(self, *args, **kw):
self.file.write('\n')
self.file.write('-'*self.maxcol)
self.file.write('\n')
self.col = 0
self.atbreak = 0
def send_literal_data(self, data):
self.file.write(data)
i = string.rfind(data, '\n')
if i >= 0:
self.col = 0
data = data[i+1:]
data = string.expandtabs(data)
self.col = self.col + len(data)
self.atbreak = 0
def send_flowing_data(self, data):
if not data: return
atbreak = self.atbreak or data[0] in string.whitespace
col = self.col
maxcol = self.maxcol
write = self.file.write
for word in string.split(data):
if atbreak:
if col + len(word) >= maxcol:
write('\n')
col = 0
else:
write(' ')
col = col + 1
write(word)
col = col + len(word)
atbreak = 1
self.col = col
self.atbreak = data[-1] in string.whitespace
def test(file = None):
w = DumbWriter()
f = AbstractFormatter(w)
if file:
fp = open(file)
elif sys.argv[1:]:
fp = open(sys.argv[1])
else:
fp = sys.stdin
while 1:
line = fp.readline()
if not line:
break
if line == '\n':
f.end_paragraph(1)
else:
f.add_flowing_data(line)
f.end_paragraph(0)
if __name__ == '__main__':
test()