Fix directive arguments

Author: i80and

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Fixed
+
+- Directive arguments were not being properly migrated in the AST.
+
 ## [v0.5.1] - 2020-07-15
 
 ### Added

snooty/n.py

@@ -257,7 +257,7 @@ class Directive(Parent[Node]):
     type = "directive"
     domain: str
     name: str
-    argument: List["Text"]
+    argument: MutableSequence["Text"]
     options: Dict[str, str]
 
     def verify(self) -> None:

snooty/parser.py

@@ -385,20 +385,26 @@ def handle_directive(
 
         doc = n.Directive((line,), [], domain, name, [], options)
 
-        if (
-            node.children
-            and node.children[0].__class__.__name__ == "directive_argument"
-        ):
-            visitor = self.__make_child_visitor()
-            node.children[0].walkabout(visitor)
-            top_of_visitor_state = visitor.state[-1]
-            assert isinstance(top_of_visitor_state, n.Parent)
-            argument = top_of_visitor_state.children
-            doc.argument = argument  # type: ignore
-            node.children = node.children[1:]
-        else:
-            argument = []
-            doc.argument = argument
+        # Find and move the argument from the children to the "argument" field.
+        argument: MutableSequence[Any] = []
+        if node.children:
+            index_of_argument = next(
+                (
+                    idx
+                    for idx, value in enumerate(node.children)
+                    if isinstance(value, rstparser.directive_argument)
+                ),
+                None,
+            )
+            if index_of_argument is not None:
+                visitor = self.__make_child_visitor()
+                node.children[index_of_argument].walkabout(visitor)
+                top_of_visitor_state = visitor.state[-1]
+                assert isinstance(top_of_visitor_state, n.Parent)
+                argument = top_of_visitor_state.children
+                del node.children[index_of_argument]
+
+        doc.argument = argument
 
         argument_text = None
         try:

snooty/test_parser.py

@@ -1595,7 +1595,7 @@ def test_deprecated() -> None:
     assert len(diagnostics) == 1
     check_ast_testing_string(
         page.ast,
-        """<root><directive name="raw"><directive_argument><text>html</text></directive_argument><FixedTextElement /></directive></root>""",
+        """<root><directive name="raw"><text>html</text><FixedTextElement /></directive></root>""",
     )
 
 

stubs/docutils/nodes.pyi

@@ -1,6 +1,6 @@
 import docutils.nodes
 import docutils.utils
-from typing import Any, Optional, Sequence, Iterable, Union
+from typing import Any, Optional, List, Iterable, Union
 from typing_extensions import Protocol
 
 
@@ -17,7 +17,7 @@ class Node:
     line: Optional[int]
     parent: Optional[Node]
     document: Optional[Node]
-    children: Sequence[Node]
+    children: List[Node]
 
     def walkabout(self, visitor: NodeVisitor) -> None: ...
     def astext(self) -> str: ...