nodes: remedy some can_contain_type omissions, document EscapedTag issue.

Author: kivikakk

src/nodes.rs

@@ -666,8 +666,6 @@ impl<'a> From<Ast> for AstNode<'a> {
 /// Validation errors produced by [Node::validate].
 #[derive(Debug, Clone)]
 pub enum ValidationError<'a> {
-    /// Children were found for a node that isn't supposed to have chilrden.
-    UnexpectedChildren(&'a AstNode<'a>),
     /// The type of a child node is not allowed in the parent node. This can happen when an inline
     /// node is found in a block container, a block is found in an inline node, etc.
     InvalidChildType {
@@ -756,7 +754,16 @@ pub fn can_contain_type<'a>(node: &'a AstNode<'a>, child: &NodeValue) -> bool {
         | NodeValue::Strong
         | NodeValue::Link(..)
         | NodeValue::Image(..)
-        | NodeValue::WikiLink(..) => !child.block(),
+        | NodeValue::WikiLink(..)
+        | NodeValue::Strikethrough
+        | NodeValue::Superscript
+        | NodeValue::SpoileredText
+        | NodeValue::Underline
+        // XXX: this is quite a hack: the EscapedTag _contains_ whatever was
+        // possibly going to fall into the spoiler. This should be fixed in
+        // inlines.
+        | NodeValue::EscapedTag(_)
+        => !child.block(),
 
         NodeValue::Table(..) => matches!(*child, NodeValue::TableRow(..)),
 
@@ -775,22 +782,30 @@ pub fn can_contain_type<'a>(node: &'a AstNode<'a>, child: &NodeValue) -> bool {
                 | NodeValue::HtmlInline(..)
                 | NodeValue::Math(..)
                 | NodeValue::WikiLink(..)
+                | NodeValue::FootnoteReference(..)
+                | NodeValue::Superscript
+                | NodeValue::SpoileredText
+                | NodeValue::Underline
         ),
 
         #[cfg(feature = "shortcodes")]
         NodeValue::TableCell => matches!(
             *child,
             NodeValue::Text(..)
-                | NodeValue::Code(..)
-                | NodeValue::Emph
-                | NodeValue::Strong
-                | NodeValue::Link(..)
-                | NodeValue::Image(..)
-                | NodeValue::ShortCode(..)
-                | NodeValue::Strikethrough
-                | NodeValue::HtmlInline(..)
-                | NodeValue::Math(..)
-                | NodeValue::WikiLink(..)
+            | NodeValue::Code(..)
+            | NodeValue::Emph
+            | NodeValue::Strong
+            | NodeValue::Link(..)
+            | NodeValue::Image(..)
+            | NodeValue::Strikethrough
+            | NodeValue::HtmlInline(..)
+            | NodeValue::Math(..)
+            | NodeValue::WikiLink(..)
+            | NodeValue::FootnoteReference(..)
+            | NodeValue::Superscript
+            | NodeValue::SpoileredText
+            | NodeValue::Underline
+            | NodeValue::ShortCode(..)
         ),
 
         NodeValue::MultilineBlockQuote(_) => {

src/tests/commonmark.rs

@@ -26,10 +26,9 @@ fn commonmark_avoids_spurious_backslash() {
 
     let p1 = ast(NodeValue::Paragraph);
     p1.append(ast(NodeValue::Text("Line 1".to_owned())));
+    p1.append(ast(NodeValue::LineBreak));
     root.append(p1);
 
-    root.append(ast(NodeValue::LineBreak));
-
     let p2 = ast(NodeValue::Paragraph);
     p2.append(ast(NodeValue::Text("Line 2".to_owned())));
     root.append(p2);