Add docstring transform

src/doc/common/static/custom-furo.css

@@ -21,3 +21,9 @@ a.pdf:hover {
   text-decoration: none;
 }
 
+
+/* For sections INPUT, OUTPUT, EXAMPLES, etc. */
+
+abbr {
+  font-weight: 500;
+}

src/sage/misc/sagedoc_conf.py

@@ -19,6 +19,7 @@
 # The reST default role (used for this markup: `text`) to use for all documents.
 default_role = 'math'
 
+
 def process_docstring_aliases(app, what, name, obj, options, docstringlines):
     """
     Change the docstrings for aliases to point to the original object.
@@ -27,6 +28,7 @@ def process_docstring_aliases(app, what, name, obj, options, docstringlines):
     if hasattr(obj, '__name__') and obj.__name__ != basename:
         docstringlines[:] = ['See :obj:`%s`.' % name]
 
+
 def process_directives(app, what, name, obj, options, docstringlines):
     """
     Remove 'nodetex' and other directives from the first line of any
@@ -39,6 +41,7 @@ def process_directives(app, what, name, obj, options, docstringlines):
     if 'nodetex' in directives:
         docstringlines.pop(0)
 
+
 def process_docstring_cython(app, what, name, obj, options, docstringlines):
     """
     Remove Cython's filename and location embedding.
@@ -52,6 +55,7 @@ def process_docstring_cython(app, what, name, obj, options, docstringlines):
         docstringlines.pop(0)
         docstringlines.pop(0)
 
+
 def process_docstring_module_title(app, what, name, obj, options, docstringlines):
     """
     Removes the first line from the beginning of the module's docstring.  This
@@ -74,6 +78,7 @@ def process_docstring_module_title(app, what, name, obj, options, docstringlines
         else:
             break
 
+
 def process_dollars(app, what, name, obj, options, docstringlines):
     r"""
     Replace dollar signs with backticks.
@@ -87,6 +92,7 @@ def process_dollars(app, what, name, obj, options, docstringlines):
         for i in range(len(lines)):
             docstringlines[i] = lines[i]
 
+
 def process_inherited(app, what, name, obj, options, docstringlines):
     """
     If we're including inherited members, omit their docstrings.
@@ -110,6 +116,7 @@ def process_inherited(app, what, name, obj, options, docstringlines):
     for i in range(len(docstringlines)):
         docstringlines.pop()
 
+
 def skip_TESTS_block(app, what, name, obj, options, docstringlines):
     """
     Skip blocks labeled "TESTS:".
@@ -127,6 +134,7 @@ def skip_TESTS_block(app, what, name, obj, options, docstringlines):
     while len(docstringlines) > len(lines):
         del docstringlines[len(lines)]
 
+
 class SagemathTransform(Transform):
     """
     Transform for code-blocks.
@@ -146,6 +154,7 @@ def apply(self):
                 node.rawsource = source
                 node[:] = [nodes.Text(source)]
 
+
 # This is only used by sage.misc.sphinxify
 def setup(app):
     app.connect('autodoc-process-docstring', process_docstring_cython)

src/sage_docbuild/conf.py

@@ -853,6 +853,85 @@ def apply(self):
                     node.parent.insert(node.parent.index(node) + 1, cell_node)
 
 
+class DocstringTransform(SphinxTransform):
+    r"""
+    Transform sections in Sage docstrings for better rendering.
+
+    The following are tests.
+
+    AUTHORS:
+
+    - Alice
+    - Bob
+
+    INPUT:
+
+    - one
+    - two
+
+    OUTPUT:
+
+    three
+
+    OUTPUT: three
+
+    EXAMPLE::
+
+        sage: 1 + 2
+        3
+
+    EXAMPLES::
+
+        sage: 1 + 2
+        3
+
+    EXAMPLE:
+
+    We show that `1 + 2 = 3`::
+
+        sage: 1 + 2
+        3
+
+    EXAMPLES:
+
+    We show that `1 + 2 = 3`::
+
+        sage: 1 + 2
+        3
+
+    """
+    default_priority = 600
+
+    def apply(self):
+        for node in self.document.traverse(nodes.paragraph):
+            if isinstance(node.children[0], nodes.Text) and node.children[0].astext().strip() == 'AUTHORS:':
+                list_node = node.next_node(siblings=True, descend=False)
+                if isinstance(list_node, nodes.bullet_list):
+                    new_node = nodes.admonition(classes=['authors'], admonitionclass='authors')
+                    node.replace_self(new_node)
+                    node = new_node
+                    admonition_title = nodes.title()
+                    admonition_title.append(nodes.Text('Authors'))
+                    node.insert(0, admonition_title)
+                    node.append(list_node)
+                    node.parent.remove(list_node)
+            if isinstance(node.children[0], nodes.Text):
+                text = node.children[0].astext()
+                for section in ['INPUT', 'OUTPUT', 'EXAMPLES', 'EXAMPLE', 'TESTS', 'TEST',
+                                'ALGORITHM', 'REFERENCE', 'REFERENCES']:
+                    if text.startswith(f'{section}:'):
+                        parent = node.parent
+                        index = parent.index(node)
+                        parent.remove(node)
+                        acronym_node = nodes.abbreviation()
+                        acronym_node += nodes.Text(section)
+                        para = nodes.paragraph()
+                        para += acronym_node
+                        para += nodes.Text(text[len(f'{section}:'):])
+                        parent.insert(index, para)
+                        break
+
+
 # This replaces the setup() in sage.misc.sagedoc_conf
 def setup(app):
     app.connect('autodoc-process-docstring', process_docstring_cython)
@@ -864,6 +943,7 @@ def setup(app):
         app.connect('autodoc-process-docstring', skip_TESTS_block)
     app.connect('autodoc-skip-member', skip_member)
     app.add_transform(SagemathTransform)
+    app.add_transform(DocstringTransform)
     if os.environ.get('SAGE_LIVE_DOC', 'no') == 'yes':
         app.add_transform(SagecodeTransform)