qdoc: properly implement \typealias command

\typealias was already a command recognized by QDoc, but it was simply
treated as a synonym for \typedef and was not documented. Implement
proper support for the command:

 - Add [alias] designation both in type summary and details.
 - Auto-generate information about the aliased type, including a link
   if aliasing a public, documented type.
 - Auto-convert aliases documented with \typedef to type aliases.
 - Add basic support for aliases also to DocBook and WebXML generators.
 - Document \typealias.

Fixes: QTBUG-82712
Change-Id: Iafa8c7def0a7488d7521fbc2862290a9bb3167ff
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Paul Wicking <paul.wicking@qt.io>

1 files changed, 12 insertions, 3 deletions

diff --git a/src/qdoc/tree.cpp b/src/qdoc/tree.cpp
index f6477b6b1..e20b8cc65 100644
--- a/src/qdoc/tree.cpp
+++ b/src/qdoc/tree.cpp
@@ -355,11 +355,14 @@ void Tree::resolveCppToQmlLinks()
 /*!
   For each C++ class node, resolve any \c using clauses
   that appeared in the class declaration.
+
+  For type aliases, resolve the aliased node.
  */
-void Tree::resolveUsingClauses()
+void Tree::resolveUsingClauses(Aggregate *parent)
 {
-    const NodeList &children = root_.childNodes();
-    for (auto *child : children) {
+    if (!parent)
+        parent = &root_;
+    for (auto *child : parent->childNodes()) {
         if (child->isClassNode()) {
             ClassNode *cn = static_cast<ClassNode *>(child);
             QVector<UsingClause> &usingClauses = cn->usingClauses();
@@ -370,7 +373,13 @@ void Tree::resolveUsingClauses()
                         usingClause.setNode(n);
                 }
             }
+        } else if (child->isTypeAlias()) {
+            TypeAliasNode *ta = static_cast<TypeAliasNode *>(child);
+            ta->setAliasedNode(qdb_->findNodeForTarget(ta->aliasedType(), child->parent()));
         }
+
+    if (child->genus() == Node::CPP && child->isAggregate())
+        resolveUsingClauses(static_cast<Aggregate *>(child));
     }
 }