# encoding: utf-8
"""Tools for preparing code to be run in the REPL (removing blank lines,
etc)"""
from bpython.lazyre import LazyReCompile
# TODO specifically catch IndentationErrors instead of any syntax errors
indent_empty_lines_re = LazyReCompile(r'\s*')
tabs_to_spaces_re = LazyReCompile(r'^\t+')
def indent_empty_lines(s, compiler):
"""Indents blank lines that would otherwise cause early compilation
Only really works if starting on a new line"""
lines = s.split('\n')
ends_with_newline = False
if lines and not lines[-1]:
ends_with_newline = True
lines.pop()
result_lines = []
for p_line, line, n_line in zip([''] + lines[:-1], lines,
lines[1:] + ['']):
if len(line) == 0:
p_indent = indent_empty_lines_re.match(p_line).group()
n_indent = indent_empty_lines_re.match(n_line).group()
result_lines.append(min([p_indent, n_indent], key=len) + line)
else:
result_lines.append(line)
return '\n'.join(result_lines) + ('\n' if ends_with_newline else '')
def leading_tabs_to_spaces(s):
lines = s.split('\n')
result_lines = []
def tab_to_space(m):
return len(m.group()) * 4 * ' '
for line in lines:
result_lines.append(tabs_to_spaces_re.sub(tab_to_space, line))
return '\n'.join(result_lines)
def preprocess(s, compiler):
return indent_empty_lines(leading_tabs_to_spaces(s), compiler)