highlight filter: pass metadata as an optional argument

IPython/nbconvert/filters/highlight.py

@@ -39,45 +39,51 b' __all__ = ['
     'highlight2latex'
 ]
 
-def highlight2html(cell, language='ipython'):
+def highlight2html(source, metadata=None, language='ipython'):
     """
     Return a syntax-highlighted version of the input source as html output.
 
     Parameters
     ----------
-    cell : NotebookNode cell
-        cell to highlight
+    source : str
+        source of the cell to highlight.
+    metadata : NotebookNode cell metadata
+        metadata of the cell to highlight.
     language : str
         Language to highlight the syntax of.
     """
 
-    return _pygment_highlight(cell, HtmlFormatter(), language)
+    return _pygment_highlight(source, HtmlFormatter(), metadata, language)
 
 
-def highlight2latex(cell, language='ipython'):
+def highlight2latex(source, metadata=None, language='ipython'):
     """
     Return a syntax-highlighted version of the input source as latex output.
 
     Parameters
     ----------
-    cell : NotebookNode cell
-        cell to highlight
+    source : str
+        source of the cell to highlight.
+    metadata : NotebookNode cell metadata
+        metadata of the cell to highlight.
     language : str
         Language to highlight the syntax of.
     """
-    return _pygment_highlight(cell, LatexFormatter(), language)
+    return _pygment_highlight(source, LatexFormatter(), metadata, language)
 
 
 
-def _pygment_highlight(cell, output_formatter, language='ipython'):
+def _pygment_highlight(source, output_formatter, metadata=None, language='ipython'):
     """
     Return a syntax-highlighted version of the input source
 
     Parameters
     ----------
-    cell : NotebookNode cell
-        cell to highlight
+    source : str
+        source of the cell to highlight.
     output_formatter : Pygments formatter
+    metadata : NotebookNode cell metadata
+        metadata of the cell to highlight.
     language : str
         Language to highlight the syntax of.
     """
@@ -85,14 +91,14 b" def _pygment_highlight(cell, output_formatter, language='ipython'):"
     # If the cell uses a magic extension language,
     # use the magic language instead.
     if language == 'ipython' \
-        and 'metadata' in cell \
-        and 'magics_language' in cell['metadata']:
+        and metadata \
+        and 'magics_language' in metadata:
 
-        language = cell['metadata']['magics_language']
+        language = metadata['magics_language']
 
     if language == 'ipython':
         lexer = IPythonLexer()
     else:
         lexer = get_lexer_by_name(language, stripall=True)
 
-    return pygements_highlight(cell['input'], lexer, output_formatter)
+    return pygements_highlight(source, lexer, output_formatter)

IPython/nbconvert/filters/tests/test_highlight.py

@@ -60,6 +60,6 b' class TestHighlight(TestsBase):'
 
     def _try_highlight(self, method, test, tokens):
         """Try highlighting source, look for key tokens"""
-        results = method({'input': test})
+        results = method(test)
         for token in tokens:
             assert token in results

IPython/nbconvert/templates/html_basic.tpl

@@ -36,7 +36,7 b' In [{{ cell.prompt_number }}]:'
 
 {% block input %}
 <div class="input_area box-flex1">
-{{ cell | highlight2html }}
+{{ cell.input | highlight2html(metadata=cell.metadata) }}
 </div>
 {%- endblock input %}
 

IPython/nbconvert/templates/latex/sphinx.tplx

@@ -284,7 +284,7 b' Note: For best display, use latex syntax highlighting. =))'
         \vspace{-25pt}
 
         % Add contents below.
-        ((( cell | highlight2latex )))
+        ((( cell.input | highlight2latex(metadata=cell.metadata) )))
 
     ((* elif resources.sphinx.outputstyle == 'notebook' *))
         \vspace{6pt}
@@ -292,7 +292,7 b' Note: For best display, use latex syntax highlighting. =))'
         \vspace{-2.65\baselineskip}
         \begin{ColorVerbatim}
             \vspace{-0.7\baselineskip}
-            ((( cell | highlight2latex )))
+            ((( cell.input | highlight2latex(metadata=cell.metadata) )))
             ((* if cell.input == None or cell.input == '' *))
                 \vspace{0.3\baselineskip}
             ((* else *))