Jinja2 filter that mimicks PHP's nl2br

jinja2_linebreaks.py

import re
from jinja2 import evalcontextfilter, Undefined, Markup, escape

paragraph_re = re.compile(r'(?:\r\n|\r|\n){2,}')

@app.template_filter()
@evalcontextfilter
def linebreaks(eval_ctx, value):
    if value is None or isinstance(value, Undefined):
        return ''
    
    result = u'\n\n'.join( '<p>%s</p>' % str(p).replace('\n', '<br/>'\n') \
        for p in paragraph_re.split(escape(value)) )
    if eval_ctx.autoescape:
        result = Markup(result)
    
    return result