Merge pull request #3601 from minrk/headingmath2

Markdown in heading cells (take 2)

closes  #3053
closes  #3597

IPython/html/static/notebook/js/textcell.js

@@ -27,7 +27,7 b' var IPython = (function (IPython) {'
      *
      * @class TextCell
      * @constructor TextCell
-     * @extend Ipython.Cell
+     * @extend IPython.Cell
      * @param {object|undefined} [options]
      *      @param [options.cm_config] {object} config to pass to CodeMirror, will extend/overwrite default config
      *      @param [options.placeholder] {string} default string to use when souce in empty for rendering (only use in some TextCell subclass)
@@ -285,7 +285,7 b' var IPython = (function (IPython) {'
     /**
      * @class MarkdownCell
      * @constructor MarkdownCell
-     * @extends Ipython.HtmlCell
+     * @extends IPython.HTMLCell
      */
     var MarkdownCell = function (options) {
         var options = options || {};
@@ -342,7 +342,7 b' var IPython = (function (IPython) {'
     /**
      * @class RawCell
      * @constructor RawCell
-     * @extends Ipython.TextCell
+     * @extends IPython.TextCell
      */
     var RawCell = function (options) {
 
@@ -437,12 +437,12 b' var IPython = (function (IPython) {'
 
     /**
      * @class HeadingCell
-     * @extends Ipython.TextCell
+     * @extends IPython.TextCell
      */
 
     /**
      * @constructor HeadingCell
-     * @extends Ipython.TextCell
+     * @extends IPython.TextCell
      */
     var HeadingCell = function (options) {
 
@@ -501,24 +501,8 b' var IPython = (function (IPython) {'
     };
 
 
-    HeadingCell.prototype.set_rendered = function (text) {
-        var r = this.element.find("div.text_cell_render");
-        r.empty();
-        var link = text.replace(/ /g, '_');
-        r.append(
-            $('<h'+this.level+'/>')
-            .append(
-            $('<a/>')
-                .addClass('heading-anchor')
-                .attr('id', link)
-                .html(text)
-            ).append(
-            $('<a/>')
-                .addClass('anchor-link')
-                .attr('href', '#' + link)
-                .text('¶')
-            )
-        );
+    HeadingCell.prototype.set_rendered = function (html) {
+        this.element.find("div.text_cell_render").html(html);
     };
 
 
@@ -531,8 +515,24 b' var IPython = (function (IPython) {'
     HeadingCell.prototype.render = function () {
         if (this.rendered === false) {
             var text = this.get_text();
+            // Markdown headings must be a single line
+            text = text.replace(/\n/g, ' ');
             if (text === "") { text = this.placeholder; }
-            this.set_rendered(text);
+            text = Array(this.level + 1).join("#") + " " + text;
+            text = IPython.mathjaxutils.remove_math(text);
+            var html = marked.parser(marked.lexer(text));
+            var h = $(IPython.mathjaxutils.replace_math(html));
+            // add id and linkback anchor
+            var hash = h.text().replace(/ /g, '-');
+            h.attr('id', hash);
+            h.append(
+                $('<a/>')
+                    .addClass('anchor-link')
+                    .attr('href', '#' + hash)
+                    .text('¶')
+            );
+            
+            this.set_rendered(h);
             this.typeset();
             this.element.find('div.text_cell_input').hide();
             this.element.find("div.text_cell_render").show();

IPython/html/static/notebook/less/textcell.less

@@ -19,11 +19,6 b' div.text_cell_render {'
     color: @textColor;
 }
 
-a.heading-anchor {
-  text-decoration: none;
-  color: inherit;
-}
-
 a.anchor-link:link {
   text-decoration: none;
   padding: 0px 20px;

IPython/html/static/style/style.min.css

@@ -1559,7 +1559,6 b' span#checkpoint_status,span#autosave_status{font-size:small;}'
 @media (max-width:767px){span#save_widget{font-size:small;} span#checkpoint_status,span#autosave_status{font-size:x-small;}}@media (max-width:767px){span#checkpoint_status,span#autosave_status{display:none;}}@media (min-width:768px) and (max-width:979px){span#checkpoint_status{display:none;} span#autosave_status{font-size:x-small;}}div.text_cell{padding:5px 5px 5px 5px;}
 div.text_cell_input{color:#000000;border:1px solid #cfcfcf;border-radius:4px;background:#f7f7f7;}
 div.text_cell_render{outline:none;resize:none;width:inherit;border-style:none;padding:5px;color:#000000;}
-a.heading-anchor{text-decoration:none;color:inherit;}
 a.anchor-link:link{text-decoration:none;padding:0px 20px;visibility:hidden;}
 h1:hover .anchor-link,h2:hover .anchor-link,h3:hover .anchor-link,h4:hover .anchor-link,h5:hover .anchor-link,h6:hover .anchor-link{visibility:visible;}
 .toolbar{padding:0px 10px;margin-top:-5px;}.toolbar select,.toolbar label{width:auto;height:26px;vertical-align:middle;margin-right:2px;margin-bottom:0px;display:inline;font-size:92%;margin-left:0.3em;margin-right:0.3em;padding:0px;padding-top:3px;}

IPython/nbconvert/exporters/exporter.py

@@ -57,6 +57,8 b' default_filters = {'
         'rm_ansi': filters.remove_ansi,
         'rm_dollars': filters.strip_dollars,
         'rm_fake': filters.rm_fake,
+        'html_text' : filters.html_text,
+        'add_anchor': filters.add_anchor,
         'ansi2latex': filters.ansi2latex,
         'rm_math_space': filters.rm_math_space,
         'wrap': filters.wrap

IPython/nbconvert/filters/markdown.py

@@ -52,7 +52,7 b' def markdown2latex(source):'
 
 def markdown2html(source):
     """Convert a markdown string to HTML via pandoc"""
-    return pandoc(source, 'markdown', 'html')
+    return pandoc(source, 'markdown', 'html', extra_args=['--mathjax'])
 
 def markdown2rst(source):
     """Convert a markdown string to LaTeX via pandoc.

IPython/nbconvert/filters/strings.py

@@ -1,3 +1,4 b''
+# coding: utf-8
 """String filters.
 
 Contains a collection of useful string manipulation filters for use in Jinja
@@ -17,6 +18,9 b' templates.'
 
 import re
 import textwrap
+from xml.etree import ElementTree
+
+from IPython.utils import py3compat
 
 #-----------------------------------------------------------------------------
 # Functions
@@ -24,6 +28,8 b' import textwrap'
 
 __all__ = [
     'wrap',
+    'html_text',
+    'add_anchor',
     'strip_dollars',
     'rm_fake',
     'python_comment',
@@ -50,6 +56,35 b' def wrap(text, width=100):'
     return '\n'.join(wrpd)
 
 
+def html_text(element):
+    """extract inner text from html
+    
+    Analog of jQuery's $(element).text()
+    """
+    if not isinstance(element, (ElementTree.ElementTree, ElementTree.Element)):
+        element = ElementTree.fromstring(element)
+    
+    text = element.text or ""
+    for child in element:
+        text += html_text(child)
+    text += (element.tail or "")
+    return text
+
+
+def add_anchor(html):
+    """Add an anchor-link to an html header tag
+    
+    For use in heading cells
+    """
+    h = ElementTree.fromstring(py3compat.cast_bytes_py2(html))
+    link = html_text(h).replace(' ', '-')
+    h.set('id', link)
+    a = ElementTree.Element("a", {"class" : "anchor-link", "href" : "#" + link})
+    a.text = u'¶'
+    h.append(a)
+    return ElementTree.tostring(h)
+
+
 def strip_dollars(text):
     """
     Remove all dollar symbols from text

IPython/nbconvert/templates/basichtml.tpl

@@ -59,12 +59,7 b' Out[{{cell.prompt_number}}]:'
 
 {% block headingcell scoped %}
 <div class="text_cell_render border-box-sizing rendered_html">
-<h{{cell.level}}>
-{% set source = cell.source | replace(' ','_') %}
-<a class="heading-anchor" id="{{source}}" href="#{{source}}">
-  {{cell.source | markdown| rm_fake}}
-</a>
-</h{{cell.level}}>
+  {{("#" * cell.level + cell.source) | replace('\n', ' ') | markdown | rm_fake | add_anchor }}
 </div>
 {% endblock headingcell %}
 

IPython/nbconvert/templates/latex/base.tplx

@@ -87,22 +87,7 b' it introduces a new line'
 ((* endblock markdowncell *))
 
 ((* block headingcell scoped -*))
-    \
-    ((*- if cell.level == 1 -*))
-        ((* block h1 -*))section((* endblock h1 -*))
-    ((*- elif cell.level == 2 -*))
-        ((* block h2 -*))subsection((* endblock h2 -*))
-    ((*- elif cell.level == 3 -*))
-        ((* block h3 -*))subsubsection((* endblock h3 -*))
-    ((*- elif cell.level == 4 -*))
-        ((* block h4 -*))paragraph((* endblock h4 -*))
-    ((*- elif cell.level == 5 -*))
-        ((* block h5 -*))subparagraph((* endblock h5 -*))
-    ((*- elif cell.level == 6 -*))
-        ((* block h6 -*))subparagraph((* endblock h6 -*))
-        ((= 6th level not available in standard latex =))
-
-    ((*- endif -*)){((( cell.source | markdown2latex )))}
+    ((( ('#' * cell.level + cell.source) | replace('\n', ' ') | markdown2latex )))
 ((* endblock headingcell *))
 
 ((* block rawcell scoped *))

IPython/nbconvert/templates/markdown.tpl

@@ -61,7 +61,7 b' $$'
 
 {% block headingcell scoped %}
 
-{{ '#' * cell.level }} {{ cell.source }}
+{{ '#' * cell.level }} {{ cell.source | replace('\n', ' ') }}
 
 {% endblock headingcell %}
 

IPython/nbconvert/templates/python.tpl

@@ -44,7 +44,7 b' it introduces a new line'
 {% endblock markdowncell %}
 
 {% block headingcell scoped %}
-{{ '#' * cell.level }}{{ cell.source | pycomment}}
+{{ '#' * cell.level }}{{ cell.source | replace('\n', ' ') | pycomment}}
 {% endblock headingcell %}
 
 {% block rawcell scoped %}

IPython/nbconvert/templates/rst.tpl

@@ -63,21 +63,7 b' Out[{{cell.prompt_number}}]:{% endif %}{% endblock output_prompt %}'
 {% endblock markdowncell %}
 
 {% block headingcell scoped %}
-{%- set len = cell.source|length -%}
-{{ cell.source | markdown2rst }}
-{% if cell.level == 1 %}
-{{- '=' * len }}
-{%- elif cell.level == 2 %}
-{{- '-' * len }}
-{%- elif cell.level == 3 %}
-{{- '~' * len }}
-{%- elif cell.level == 4 %}
-{{- '.' * len }}
-{%- elif cell.level == 5 %}
-{{- '\\' * len }}
-{%- elif cell.level == 6 %}
-{{- '`' * len }}
-{% endif %}
+{{ ("#" * cell.level + cell.source) | replace('\n', ' ') | markdown2rst }}
 
 {% endblock headingcell %}
 

IPython/nbconvert/utils/pandoc.py

@@ -24,7 +24,7 b' from IPython.utils.py3compat import cast_bytes'
 # Classes and functions
 #-----------------------------------------------------------------------------
 
-def pandoc(source, fmt, to, encoding='utf-8'):
+def pandoc(source, fmt, to, extra_args=None, encoding='utf-8'):
     """Convert an input string in format `from` to format `to` via pandoc.
 
     This function will raise an error if pandoc is not installed.
@@ -44,7 +44,10 b" def pandoc(source, fmt, to, encoding='utf-8'):"
     out : unicode
       Output as returned by pandoc.
     """
-    p = subprocess.Popen(['pandoc', '-f', fmt, '-t', to],
+    command = ['pandoc', '-f', fmt, '-t', to]
+    if extra_args:
+        command.extend(extra_args)
+    p = subprocess.Popen(command,
                          stdin=subprocess.PIPE, stdout=subprocess.PIPE
     )
     out, _ = p.communicate(cast_bytes(source, encoding))