moc: Fix parsing of [[deprecated]] enum values

moc now successfully parses enum values, that have been deprecated with
[[deprecated]]. This is valid c++17 and should be handled correctly.
By adding that functionality it is possible to parse Windows headers
which use this deprecation mechanism.

To make sure, that moc works correctly even on compilers that do not
support deprecated enum values yet, the auto test explicitly uses
[[deprecated]] enum values during moc run.

Fixes: QTBUG-74126
Change-Id: I7b9d9a49af6093a97f8fdb800ffbc5af3d54d262
Reviewed-by: Olivier Goffart (Woboq GmbH) <ogoffart@woboq.com>
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@qt.io>

3 files changed, 61 insertions, 0 deletions

diff --git a/src/tools/moc/moc.cpp b/src/tools/moc/moc.cpp
index d811bf09f0..2f52dd6ca0 100644
--- a/src/tools/moc/moc.cpp
+++ b/src/tools/moc/moc.cpp
@@ -285,6 +285,7 @@ bool Moc::parseEnum(EnumDef *def)
             break;
         next(IDENTIFIER);
         def->values += lexem();
+        skipCxxAttributes();
     } while (test(EQ) ? until(COMMA) : test(COMMA));
     next(RBRACE);
     if (isTypdefEnum) {
diff --git a/tests/auto/tools/moc/cxx-attributes.h b/tests/auto/tools/moc/cxx-attributes.h
index 719f31e23c..eff6a3ec41 100644
--- a/tests/auto/tools/moc/cxx-attributes.h
+++ b/tests/auto/tools/moc/cxx-attributes.h
@@ -57,4 +57,47 @@ public slots:
 #endif
 };
 
+#ifdef Q_MOC_RUN
+#  define TEST_COMPILER_DEPRECATION [[deprecated]]
+#  define TEST_COMPILER_DEPRECATION_X(x) [[deprecated(x)]]
+#else
+#  define TEST_COMPILER_DEPRECATION Q_DECL_ENUMERATOR_DEPRECATED
+#  define TEST_COMPILER_DEPRECATION_X(x) Q_DECL_ENUMERATOR_DEPRECATED_X(x)
+#endif
+
+namespace TestQNamespaceDeprecated {
+    Q_NAMESPACE
+    enum class TestEnum1 {
+        Key1 = 11,
+        Key2 TEST_COMPILER_DEPRECATION,
+        Key3 TEST_COMPILER_DEPRECATION_X("reason"),
+        Key4 TEST_COMPILER_DEPRECATION_X("reason["),
+        Key5 TEST_COMPILER_DEPRECATION_X("reason[["),
+        Key6 TEST_COMPILER_DEPRECATION_X("reason]"),
+        Key7 TEST_COMPILER_DEPRECATION_X("reason]]"),
+    };
+    Q_ENUM_NS(TestEnum1)
+
+    // try to dizzy moc by adding a struct in between
+    struct TestGadget {
+        Q_GADGET
+    public:
+        enum class TestGEnum1 {
+            Key1 = 13,
+            Key2 TEST_COMPILER_DEPRECATION,
+            Key3 TEST_COMPILER_DEPRECATION_X("reason")
+        };
+        Q_ENUM(TestGEnum1)
+    };
+
+    enum class TestFlag1 {
+        None = 0,
+        Flag1 = 1,
+        Flag2 TEST_COMPILER_DEPRECATION = 2,
+        Flag3 TEST_COMPILER_DEPRECATION_X("reason") = 3,
+        Any = Flag1 | Flag2 | Flag3
+    };
+    Q_FLAG_NS(TestFlag1)
+}
+
 #endif // CXXATTRIBUTE_H
diff --git a/tests/auto/tools/moc/tst_moc.cpp b/tests/auto/tools/moc/tst_moc.cpp
index 4e5d902aa2..f12df578f4 100644
--- a/tests/auto/tools/moc/tst_moc.cpp
+++ b/tests/auto/tools/moc/tst_moc.cpp
@@ -3926,6 +3926,23 @@ void tst_Moc::cxxAttributes()
                   }) {
         QVERIFY(so.indexOfSlot(a) != 1);
     }
+
+    QCOMPARE(TestQNamespaceDeprecated::staticMetaObject.enumeratorCount(), 2);
+    checkEnum(TestQNamespaceDeprecated::staticMetaObject.enumerator(0), "TestEnum1",
+                {{"Key1", 11}, {"Key2", 12}, {"Key3", 13}, {"Key4", 14}, {"Key5", 15}, {"Key6", 16},
+                 {"Key7", 17}});
+    checkEnum(TestQNamespaceDeprecated::staticMetaObject.enumerator(1), "TestFlag1",
+                {{"None", 0}, {"Flag1", 1}, {"Flag2", 2}, {"Flag3", 3}, {"Any", 1 | 2 | 3}});
+
+    QCOMPARE(TestQNamespaceDeprecated::TestGadget::staticMetaObject.enumeratorCount(), 1);
+    checkEnum(TestQNamespaceDeprecated::TestGadget::staticMetaObject.enumerator(0), "TestGEnum1",
+                {{"Key1", 13}, {"Key2", 14}, {"Key3", 15}});
+
+    QMetaEnum meta = QMetaEnum::fromType<TestQNamespaceDeprecated::TestEnum1>();
+    QVERIFY(meta.isValid());
+    QCOMPARE(meta.name(), "TestEnum1");
+    QCOMPARE(meta.enclosingMetaObject(), &TestQNamespaceDeprecated::staticMetaObject);
+    QCOMPARE(meta.keyCount(), 7);
 }
 
 QTEST_MAIN(tst_Moc)