Clang: Fix tooltip for pointer to class

Detect and dereference pointer to get to the correct class.

Fixes: QTCREATORBUG-21523
Change-Id: I679778b2cfbbce4466294dabdee096686f53f095
Reviewed-by: Ivan Donchevskii <ivan.donchevskii@qt.io>

src/tools/clangbackend/source/clangtooltipinfocollector.cpp

@@ -425,14 +425,24 @@ ToolTipInfo ToolTipInfoCollector::qDocInfo(const Cursor &cursor) const
         return result;
     }
 
-    if (cursor.kind() == CXCursor_VarDecl || cursor.kind() == CXCursor_FieldDecl) {
+    if (cursor.kind() == CXCursor_VarDecl || cursor.kind() == CXCursor_ParmDecl
-        result.qdocMark = typeName(cursor.type());
+        || cursor.kind() == CXCursor_FieldDecl) {
         // maybe template instantiation
         if (cursor.type().kind() == CXType_Unexposed && cursor.type().canonical().kind() == CXType_Record) {
             result.qdocIdCandidates = qDocIdCandidates(cursor.type().canonical().declaration());
+            result.qdocMark = typeName(cursor.type());
             result.qdocCategory = ToolTipInfo::ClassOrNamespace;
             return result;
         }
+
+        Type type = cursor.type();
+        while (type.pointeeType().isValid())
+            type = type.pointeeType();
+
+        const Cursor typeCursor = type.declaration();
+        result.qdocIdCandidates = qDocIdCandidates(typeCursor);
+        result.qdocCategory = qdocCategory(typeCursor);
+        result.qdocMark = typeName(type);
     }
 
     // TODO: Handle also RValueReference()

tests/unit/unittest/clangtooltipinfo-test.cpp

@@ -584,6 +584,18 @@ TEST_F(ToolTipInfo, AutoTypeBuiltin)
     ASSERT_THAT(actual.text, Utf8StringLiteral("int"));
 }
 
+TEST_F(ToolTipInfo, PointerToPointerToClass)
+{
+    ::ToolTipInfo expected(Utf8StringLiteral("Nuu **"));
+    expected.qdocIdCandidates = {Utf8StringLiteral("Nuu")};
+    expected.qdocMark = Utf8StringLiteral("Nuu");
+    expected.qdocCategory = ::ToolTipInfo::ClassOrNamespace;
+
+    const ::ToolTipInfo actual = tooltip(200, 12);
+
+    ASSERT_THAT(actual, IsToolTip(expected));
+}
+
 // TODO: Test for qdoc entries, too.
 TEST_F(ToolTipInfo, AutoTypeEnum)
 {

tests/unit/unittest/data/tooltipinfo.cpp

@@ -194,3 +194,8 @@ void constructor()
     ExplicitCon();
     ExplicitCon(2);
 }
+
+Nuu **pointers(Nuu **p1)
+{
+    return p1;
+}