doc_stack/special_methods (#1855)

* initial commit for doc_stack/special_methods

* Add sphinxcontrib.prettyspecialmethods

* Switch to fork of prettyspecialmethods

* fix

* fix

doc/conf.py

@@ -36,6 +36,7 @@
     'show-inheritance': True
 }
 toc_object_entries_show_parents = 'hide'
+prettyspecialmethods_signature_prefix = '🧙'
 
 sys.path.insert(0, os.path.abspath('..'))
 sys.path.insert(0, os.path.abspath('../arcade'))
@@ -64,6 +65,7 @@
     'sphinx.ext.viewcode',
     'sphinx_copybutton',
     'sphinx_sitemap',
+    'doc.extensions.prettyspecialmethods'
 ]
 
 # --- Spell check. Never worked well.

doc/extensions/prettyspecialmethods.py

@@ -0,0 +1,297 @@
+# This is a fork of https://github.com/sphinx-contrib/prettyspecialmethods / https://pypi.org/project/sphinxcontrib-prettyspecialmethods/
+# Specifically, it is based off the modified version linked from this issue:
+# https://github.com/sphinx-contrib/prettyspecialmethods/issues/16
+
+"""
+    sphinxcontrib.prettyspecialmethods
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+    Shows special methods as the python syntax that invokes them
+
+    :copyright: Copyright 2018 by Thomas Smith
+    :license: MIT, see LICENSE for details.
+"""
+
+# import pbr.version
+import sphinx.addnodes as SphinxNodes
+from docutils import nodes
+from docutils.nodes import Text
+from typing import TYPE_CHECKING, List, Tuple
+import sphinx.domains.python
+from sphinx.domains.python import py_sig_re
+from docutils.parsers.rst import directives
+import sphinx.ext.autodoc
+
+
+# __version__ = pbr.version.VersionInfo(
+#     'prettyspecialmethods').version_string()
+
+
+ATTR_TOC_SIG = '_prettyspecialmethods_sig'
+CONF_SIG_PREFIX = 'prettyspecialmethods_signature_prefix'
+
+
+def self_identifier(name = 'self'):
+    # Format like a parameter, though we cannot use desc_parameter because it
+    # causes error in html emitter
+    return SphinxNodes.desc_sig_name('', name)
+
+
+# Parameter nodes cannot be used outside of a parameterlist, because it breaks
+# the html emitter.  So we unpack their contents.
+# Better than astext() because it preserves references.
+def unwrap_parameter(parameters_node, index = 0):
+    if len(parameters_node.children) > index:
+        return parameters_node.children[index].children
+    return ()
+
+
+# For keywords/builtins and punctuation that describes the operator and should
+# be formatted similar to a method or attribute's name.
+# For example, in the case of `del self[index]`: `del`, `[` and `]` should be
+# formatted like the method name `__delitem__` would have been formatted.
+def operator_name(str):
+    return SphinxNodes.desc_name('', '', Text(str))
+def operator_punctuation(str):
+    return SphinxNodes.desc_name('', '', Text(str))
+
+
+# For punctuation that is not part of the operator
+def punctuation(str):
+    return SphinxNodes.desc_sig_punctuation('', str)
+
+
+def patch_node(node, text=None, children=None, *, constructor=None):
+    if constructor is None:
+        constructor = node.__class__
+
+    if text is None:
+        text = node.text
+
+    if children is None:
+        children = node.children
+
+    return constructor(
+        node.source,
+        text,
+        *children,
+        **node.attributes,
+    )
+
+
+def function_transformer(new_name):
+    def xf(name_node, parameters_node):
+        return (
+            patch_node(name_node, new_name, ()),
+            patch_node(parameters_node, '', [
+                self_identifier(),
+                *parameters_node.children,
+            ])
+        )
+
+    return xf
+
+
+def unary_op_transformer(op):
+    def xf(name_node, parameters_node):
+        return (
+            patch_node(name_node, op, ()),
+            self_identifier(),
+        )
+
+    return xf
+
+
+def binary_op_transformer(op):
+    def xf(name_node, parameters_node):
+        return (
+            self_identifier(),
+            Text(' '),
+            patch_node(name_node, op, ()),
+            Text(' '),
+            *unwrap_parameter(parameters_node)
+        )
+
+    return xf
+
+
+def brackets(parameters_node):
+    return [
+        self_identifier(),
+        operator_punctuation('['),
+        *unwrap_parameter(parameters_node),
+        operator_punctuation(']')
+    ]
+
+
+SPECIAL_METHODS = {
+    '__getitem__': lambda name_node, parameters_node: (
+        brackets(parameters_node)
+    ),
+    '__setitem__': lambda name_node, parameters_node: (
+        *brackets(parameters_node),
+        Text(' '),
+        operator_punctuation('='),
+        Text(' '),
+        *unwrap_parameter(parameters_node, 1)
+    ),
+    '__delitem__': lambda name_node, parameters_node: (
+        SphinxNodes.desc_name('', '', Text('del')),
+        Text(' '),
+        *brackets(parameters_node),
+    ),
+    '__contains__': lambda name_node, parameters_node: (
+        *unwrap_parameter(parameters_node),
+        Text(' '),
+        SphinxNodes.desc_name('', '', Text('in')),
+        Text(' '),
+        self_identifier(),
+    ),
+
+    '__await__': lambda name_node, parameters_node: (
+        SphinxNodes.desc_name('', '', Text('await')),
+        Text(' '),
+        self_identifier(),
+    ),
+
+    '__lt__': binary_op_transformer('<'),
+    '__le__': binary_op_transformer('<='),
+    '__eq__': binary_op_transformer('=='),
+    '__ne__': binary_op_transformer('!='),
+    '__gt__': binary_op_transformer('>'),
+    '__ge__': binary_op_transformer('>='),
+
+    '__hash__': function_transformer('hash'),
+    '__len__': function_transformer('len'),
+    '__iter__': function_transformer('iter'),
+    '__str__': function_transformer('str'),
+    '__repr__': function_transformer('repr'),
+
+    '__add__': binary_op_transformer('+'),
+    '__sub__': binary_op_transformer('-'),
+    '__mul__': binary_op_transformer('*'),
+    '__matmul__': binary_op_transformer('@'),
+    '__truediv__': binary_op_transformer('/'),
+    '__floordiv__': binary_op_transformer('//'),
+    '__mod__': binary_op_transformer('%'),
+    '__divmod__': function_transformer('divmod'),
+    '__pow__': binary_op_transformer('**'),
+    '__lshift__': binary_op_transformer('<<'),
+    '__rshift__': binary_op_transformer('>>'),
+    '__and__': binary_op_transformer('&'),
+    '__xor__': binary_op_transformer('^'),
+    '__or__': binary_op_transformer('|'),
+
+    '__neg__': unary_op_transformer('-'),
+    '__pos__': unary_op_transformer('+'),
+    '__abs__': function_transformer('abs'),
+    '__invert__': unary_op_transformer('~'),
+
+    '__call__': lambda name_node, parameters_node: (
+        self_identifier(),
+        patch_node(parameters_node, '', parameters_node.children)
+    ),
+    '__getattr__': function_transformer('getattr'),
+    '__setattr__': function_transformer('setattr'),
+    '__delattr__': function_transformer('delattr'),
+
+    '__bool__': function_transformer('bool'),
+    '__int__': function_transformer('int'),
+    '__float__': function_transformer('float'),
+    '__complex__': function_transformer('complex'),
+    '__bytes__': function_transformer('bytes'),
+
+    # could show this as "{:...}".format(self) if we wanted
+    '__format__': function_transformer('format'),
+
+    '__index__': function_transformer('operator.index'),
+    '__length_hint__': function_transformer('operator.length_hint'),
+    '__ceil__': function_transformer('math.ceil'),
+    '__floor__': function_transformer('math.floor'),
+    '__trunc__': function_transformer('math.trunc'),
+    '__round__': function_transformer('round'),
+
+    '__sizeof__': function_transformer('sys.getsizeof'),
+    '__dir__': function_transformer('dir'),
+    '__reversed__': function_transformer('reversed'),
+}
+
+
+class PyMethod(sphinx.domains.python.PyMethod):
+    """
+    Replacement for sphinx's built-in PyMethod directive, behaves identically
+    except for tweaks to special methods.
+    """
+
+    option_spec = sphinx.domains.python.PyMethod.option_spec.copy()
+    option_spec.update({
+        'selfparam': directives.unchanged_required,
+    })
+
+    def _get_special_method(self, sig: str):
+        "If this is a special method, return its name, otherwise None"
+        m = py_sig_re.match(sig)
+        if m is None:
+            return None
+        prefix, method_name, typeparamlist, arglist, retann = m.groups()
+        if method_name not in SPECIAL_METHODS:
+            return None
+        return method_name
+
+    def get_signature_prefix(self, sig: str) -> List[nodes.Node]:
+        prefix = super().get_signature_prefix(sig)
+        signature_prefix = getattr(self.env.app.config, CONF_SIG_PREFIX)
+        if signature_prefix:
+            method_name = self._get_special_method(sig)
+            if method_name is not None:
+                prefix.append(nodes.Text(signature_prefix))
+                prefix.append(SphinxNodes.desc_sig_space())
+        return prefix
+
+    def handle_signature(self, sig: str, signode: SphinxNodes.desc_signature) -> Tuple[str, str]:
+        method_name = self._get_special_method(sig)
+
+        result = super().handle_signature(sig, signode)
+
+        if method_name is None:
+            return result
+
+        sig_rewriter = SPECIAL_METHODS[method_name]
+        name_node = signode.next_node(SphinxNodes.desc_name)
+        parameters_node = signode.next_node(SphinxNodes.desc_parameterlist)
+
+        replacement = sig_rewriter(name_node, parameters_node)
+        parent = name_node.parent
+        parent.insert(parent.index(name_node), replacement)
+        parameters_node.replace_self(())
+        parent.remove(name_node)
+
+        # Generate TOC name by doing the same rewrite w/ typehints stripped from
+        # params, then converting to str
+        parameters_sans_types = [SphinxNodes.desc_parameter('', '', p.children[0]) for p in parameters_node.children]
+        parameters_node_sans_types = SphinxNodes.desc_parameterlist('', '',
+            *parameters_sans_types
+        )
+        replacement_w_out_types = sig_rewriter(name_node, parameters_node_sans_types)
+        toc_name = ''.join([node.astext() for node in replacement_w_out_types])
+        signode.attributes[ATTR_TOC_SIG] = toc_name
+
+        return result
+
+    def _toc_entry_name(self, sig_node: SphinxNodes.desc_signature):
+        # TODO support toc_object_entries_show_parents?
+        # How would that work?  Show class name in place of `self`?
+        return sig_node.attributes.get(ATTR_TOC_SIG, super()._toc_entry_name(sig_node))
+
+
+def show_special_methods(app, what, name, obj, skip, options):
+    if what == 'class' and name in SPECIAL_METHODS and getattr(obj, '__doc__', None):
+        return False
+
+
+def setup(app):
+    app.add_config_value(CONF_SIG_PREFIX, 'implements', True)
+    app.connect('autodoc-skip-member', show_special_methods)
+    app.registry.add_directive_to_domain('py', 'method', PyMethod)
+    # return {'version': __version__, 'parallel_read_safe': True}
+    return {'parallel_read_safe': True}