qdoc: Parse enum classes correctly

Clang provides us sufficient information to detect a scoped enum (an
enum class). For such enums, include the enum type name into the fully
qualified name of the enum values. For enums related to \headerfile
nodes, drop the '<Header>::' from the qualified name of the enum values
as they are not valid. Ensure that this also applies to all node types
in Node::plainFullName(), as including file names into a qualified path is
always incorrect.

In some cases, enum classes were also forward declared. This was a
problem as QDoc skipped the full declaration after seeing the forward
one. Combat this by re-processing the enum declarations that do not
contain any values yet.

Add relevant test case.

[ChangeLog][qdoc] QDoc now generates correct documentation for enum
classes.

Fixes: QTBUG-66740
Change-Id: I36dcb3393500acb788e0a305fd0dfecc4b58ebc3
Reviewed-by: Topi Reiniö <topi.reinio@qt.io>

1 files changed, 12 insertions, 9 deletions

diff --git a/src/qdoc/cppcodemarker.cpp b/src/qdoc/cppcodemarker.cpp
index 25c2f630b..38dd8e79f 100644
--- a/src/qdoc/cppcodemarker.cpp
+++ b/src/qdoc/cppcodemarker.cpp
@@ -221,7 +221,10 @@ QString CppCodeMarker::markedUpSynopsis(const Node *node, const Node * /* relati
         break;
     case Node::Enum:
         enume = static_cast<const EnumNode *>(node);
-        synopsis = "enum " + name;
+        synopsis = "enum ";
+        if (enume->isScoped())
+            synopsis += "class ";
+        synopsis += name;
         if (style == Section::Summary) {
             synopsis += " { ";
 
@@ -382,18 +385,18 @@ QString CppCodeMarker::markedUpEnumValue(const QString &enumValue, const Node *r
         return enumValue;
 
     const Node *node = relative->parent();
-    QString fullName;
-    while (node->parent()) {
-        fullName.prepend(markedUpName(node));
+    QStringList parts;
+    while (!node->isHeader() && node->parent()) {
+        parts.prepend(markedUpName(node));
         if (node->parent() == relative || node->parent()->name().isEmpty())
             break;
-        fullName.prepend("<@op>::</@op>");
         node = node->parent();
     }
-    if (!fullName.isEmpty())
-        fullName.append("<@op>::</@op>");
-    fullName.append(enumValue);
-    return fullName;
+    if (static_cast<const EnumNode *>(relative)->isScoped())
+        parts.append(relative->name());
+
+    parts.append(enumValue);
+    return parts.join(QLatin1String("<@op>::</@op>"));
 }
 
 QString CppCodeMarker::markedUpIncludes(const QStringList &includes)