Convert Sass to SCSS

sass_to_scss.py

import argparse
from pprint import pprint
import re


def count_leading_spaces(line):
    return len(line) - len(line.lstrip(' '))


def sass_to_scss(sass_lines):
    outlines = []
    cleaned = []

    css_rule = re.compile(r'\s+\w+:')

    for line in sass_lines:
        if line.isspace():
            continue
        cleaned.append(line.replace('\n', ''))

    for i, line in enumerate(cleaned):
        indent = count_leading_spaces(sass_lines[i])
        try:
            next_indent = count_leading_spaces(sass_lines[i + 1])
        except IndexError:
            next_indent = 0
        try:
            prev_indent = count_leading_spaces(sass_lines[i - 1])
        except IndexError:
            prev_indent = 0

        if css_rule.match(line) is not None:
            line += ';'

        if indent < next_indent:
            outlines.append(line + ' ' + '{')

        elif indent > prev_indent and indent != next_indent:
            outlines.append(line)
            closed_indent = indent
            spaces = indent - prev_indent
            while closed_indent != next_indent:
                insert = ' ' * (closed_indent - spaces) + '}'
                outlines.append(insert)
                closed_indent -= spaces

        else:
            outlines.append(line)

    return '\n'.join(outlines)

test_sass_to_scss.py

from unittest import TestCase

import sass_to_scss


class TestSassToSCSS(TestCase):

    def trim_docstring(self, docstring):
        return '\n'.join(docstring.split('\n')[1:-1])

    def test_triple_nested_class(self):
        sass = """
.container
    position: absolute
    top: 0
    color: green
    bottom: 0
    .right
        right: 0
        border: 1px solid #fff
        h1
            color: blue
    .left
        left: 0
        h1
            color: red
        """

        scss = """
.container {
    position: absolute;
    top: 0;
    color: green;
    bottom: 0;
    .right {
        right: 0;
        border: 1px solid #fff;
        h1 {
            color: blue;
        }
    }
    .left {
        left: 0;
        h1 {
            color: red;
        }
    }
}
        """

        input = self.trim_docstring(sass).split('\n')
        actual = sass_to_scss.sass_to_scss(input)
        expected = self.trim_docstring(scss)
        print actual

        self.assertEquals(expected, actual)