From 45c51f9dd5af62de9ed79abc3114112f36f0b937 Mon Sep 17 00:00:00 2001
From: Erik Stein <erik@classlibrary.net>
Date: Fri, 28 Sep 2018 13:47:48 +0200
Subject: [PATCH] Additional text template tags.

---
 CHANGES                                |  3 ++
 shared/utils/templatetags/text_tags.py | 59 +++++++++++++++++++++++++-
 2 files changed, 61 insertions(+), 1 deletion(-)

diff --git a/CHANGES b/CHANGES
index d939c71..743ffba 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,6 @@
+0.2.12 2018-09-28
+- Additional text template tags.
+
 0.2.11 2018-09-27
 - RichTextBase has no longer StyleMixin as default.
 
diff --git a/shared/utils/templatetags/text_tags.py b/shared/utils/templatetags/text_tags.py
index 2e1541d..3542009 100644
--- a/shared/utils/templatetags/text_tags.py
+++ b/shared/utils/templatetags/text_tags.py
@@ -1,8 +1,8 @@
 # -*- coding: utf-8 -*-
 from __future__ import unicode_literals
-# Erik Stein <code@classlibrary.net>, 2015
 
 import re
+import string
 
 from django import template
 from django.template.defaultfilters import stringfilter
@@ -73,3 +73,60 @@ def html_lines_to_list(value):
                 rv.append(" ")
     return "".join(rv)
     return ", ".join([l.strip() for l in value.split("<br>")])
+
+
+def remove_punctuation(s):
+    # http://stackoverflow.com/questions/265960/best-way-to-strip-punctuation-from-a-string-in-python
+    # return s.translate(s.maketrans("",""), string.punctuation)
+    regex = re.compile('[%s]' % re.escape(string.punctuation))
+    return regex.sub('', s)
+
+
+def splitn(s, n):
+    """split string s into chunks no more than n characters long"""
+    parts = re.split("(.{%d,%d})" % (n, n), s)
+    map(parts.remove, [""] * parts.count(""))
+    return parts
+
+
+def clean_value(value):
+    # Convert all whitespace including non-breaking space to a single space
+    if value:
+        return re.sub(u"([\s\u00A0]+)", u" ", force_text(value.strip()))
+    else:
+        return value
+
+
+@register.filter()
+@stringfilter
+def append(value, text):
+    """
+    Appends text if value is not None.
+    """
+    if value is not None:
+        value = str(value).strip()
+        if value:
+            return "{}{}".format(value, text)
+    return ""
+
+
+@register.filter()
+@stringfilter
+def prepend(value, text):
+    """
+    Prepends text if value is not None.
+    """
+    if value is not None:
+        value = str(value).strip()
+        if value:
+            return "{}{}".format(text, value)
+    return ""
+
+
+@register.filter
+@stringfilter
+def first_line(s):
+    """
+    Strips whitespace, then returns the first line of text.
+    """
+    return s.strip().splitlines(False)[0]