loplugin:unusedenumconstants improvements

add some unit tests, and improve the heuristics

Change-Id: I95aa97a87e178ce8d506bd245710d0ae66ad08a4
Reviewed-on: https://gerrit.libreoffice.org/63647
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
Tested-by: Noel Grandin <noel.grandin@collabora.co.uk>

1 files changed, 92 insertions, 0 deletions

diff --git a/compilerplugins/clang/test/unusedenumconstants.cxx b/compilerplugins/clang/test/unusedenumconstants.cxx
new file mode 100644
index 000000000000..3de1a65537e0
--- /dev/null
+++ b/compilerplugins/clang/test/unusedenumconstants.cxx
@@ -0,0 +1,92 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#include <o3tl/typed_flags_set.hxx>
+
+namespace test1
+{
+void test1()
+{
+    enum NameClashMode
+    {
+        NONE,
+        NO_CLASH // expected-error {{write NO_CLASH [loplugin:unusedenumconstants]}}
+    };
+    NameClashMode eNameClashMode = NO_CLASH;
+    (void)eNameClashMode;
+}
+};
+
+enum class BrowseMode
+{
+    Modules = 0x01, // expected-error {{read Modules [loplugin:unusedenumconstants]}}
+    Top = 0x02, // expected-error {{write Top [loplugin:unusedenumconstants]}}
+};
+namespace o3tl
+{
+template <> struct typed_flags<BrowseMode> : is_typed_flags<BrowseMode, 0x3>
+{
+};
+}
+BrowseMode g_flags;
+int test2(BrowseMode nMode)
+{
+    if (nMode & BrowseMode::Modules)
+        return 1;
+    g_flags |= BrowseMode::Top;
+    return 0;
+}
+
+enum class Enum3
+{
+    One = 0x01, // expected-error {{write One [loplugin:unusedenumconstants]}}
+    Two = 0x02 // expected-error {{write Two [loplugin:unusedenumconstants]}}
+};
+namespace o3tl
+{
+template <> struct typed_flags<Enum3> : is_typed_flags<Enum3, 0x3>
+{
+};
+}
+void test3_foo(Enum3);
+void test3() { test3_foo(Enum3::One | Enum3::Two); }
+
+namespace test4
+{
+enum Enum4
+{
+    ONE, // expected-error {{write ONE [loplugin:unusedenumconstants]}}
+    TWO
+};
+struct Test4Base
+{
+    Test4Base(Enum4) {}
+};
+struct Test4 : public Test4Base
+{
+    Test4()
+        : Test4Base(Enum4::ONE)
+    {
+    }
+};
+};
+
+// check that conditional operator walks up the tree
+namespace test5
+{
+enum Enum
+{
+    ONE, // expected-error {{write ONE [loplugin:unusedenumconstants]}}
+    TWO // expected-error {{write TWO [loplugin:unusedenumconstants]}}
+};
+
+Enum foo(int x) { return x == 1 ? Enum::ONE : Enum::TWO; }
+};
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */