1 files changed, 161 insertions, 0 deletions
diff --git a/clang-tools-extra/test/clang-tidy/modernize-concat-nested-namespaces.cpp b/clang-tools-extra/test/clang-tidy/modernize-concat-nested-namespaces.cpp
new file mode 100644
index 00000000000..22a92f6016d
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/modernize-concat-nested-namespaces.cpp
@@ -0,0 +1,161 @@
+// RUN: %check_clang_tidy %s modernize-concat-nested-namespaces %t -- -- -std=c++17
+
+namespace n1 {}
+
+namespace n2 {
+namespace n3 {
+void t();
+}
+namespace n4 {
+void t();
+}
+} // namespace n2
+
+namespace n5 {
+inline namespace n6 {
+void t();
+}
+} // namespace n5
+
+namespace n7 {
+void t();
+
+namespace n8 {
+void t();
+}
+} // namespace n7
+
+namespace n9 {
+namespace n10 {
+// CHECK-MESSAGES: :[[@LINE-2]]:1: warning: nested namespaces can be concatenated [modernize-concat-nested-namespaces]
+// CHECK-FIXES: namespace n9::n10
+void t();
+} // namespace n10
+} // namespace n9
+// CHECK-FIXES: }
+
+namespace n11 {
+namespace n12 {
+// CHECK-MESSAGES: :[[@LINE-2]]:1: warning: nested namespaces can be concatenated [modernize-concat-nested-namespaces]
+// CHECK-FIXES: namespace n11::n12
+namespace n13 {
+void t();
+}
+namespace n14 {
+void t();
+}
+} // namespace n12
+} // namespace n11
+// CHECK-FIXES: }
+
+namespace n15 {
+namespace n16 {
+void t();
+}
+
+inline namespace n17 {
+void t();
+}
+
+namespace n18 {
+namespace n19 {
+namespace n20 {
+// CHECK-MESSAGES: :[[@LINE-3]]:1: warning: nested namespaces can be concatenated [modernize-concat-nested-namespaces]
+// CHECK-FIXES: namespace n18::n19::n20
+void t();
+} // namespace n20
+} // namespace n19
+} // namespace n18
+// CHECK-FIXES: }
+
+namespace n21 {
+void t();
+}
+} // namespace n15
+
+namespace n22 {
+namespace {
+void t();
+}
+} // namespace n22
+
+namespace n23 {
+namespace {
+namespace n24 {
+namespace n25 {
+// CHECK-MESSAGES: :[[@LINE-2]]:1: warning: nested namespaces can be concatenated [modernize-concat-nested-namespaces]
+// CHECK-FIXES: namespace n24::n25
+void t();
+} // namespace n25
+} // namespace n24
+// CHECK-FIXES: }
+} // namespace
+} // namespace n23
+
+namespace n26::n27 {
+namespace n28 {
+namespace n29::n30 {
+// CHECK-MESSAGES: :[[@LINE-3]]:1: warning: nested namespaces can be concatenated [modernize-concat-nested-namespaces]
+// CHECK-FIXES: namespace n26::n27::n28::n29::n30
+void t() {}
+} // namespace n29::n30
+} // namespace n28
+} // namespace n26::n27
+// CHECK-FIXES: }
+
+namespace n31 {
+namespace n32 {}
+// CHECK-MESSAGES: :[[@LINE-2]]:1: warning: nested namespaces can be concatenated [modernize-concat-nested-namespaces]
+} // namespace n31
+// CHECK-FIXES-EMPTY
+
+namespace n33 {
+namespace n34 {
+namespace n35 {}
+// CHECK-MESSAGES: :[[@LINE-2]]:1: warning: nested namespaces can be concatenated [modernize-concat-nested-namespaces]
+} // namespace n34
+// CHECK-FIXES-EMPTY
+namespace n36 {
+void t();
+}
+} // namespace n33
+
+namespace n37::n38 {
+void t();
+}
+
+#define IEXIST
+namespace n39 {
+namespace n40 {
+// CHECK-MESSAGES: :[[@LINE-2]]:1: warning: nested namespaces can be concatenated [modernize-concat-nested-namespaces]
+// CHECK-FIXES: namespace n39::n40
+#ifdef IEXIST
+void t() {}
+#endif
+} // namespace n40
+} // namespace n39
+// CHECK-FIXES: }
+
+namespace n41 {
+namespace n42 {
+// CHECK-MESSAGES: :[[@LINE-2]]:1: warning: nested namespaces can be concatenated [modernize-concat-nested-namespaces]
+// CHECK-FIXES: namespace n41::n42
+#ifdef IDONTEXIST
+void t() {}
+#endif
+} // namespace n42
+} // namespace n41
+// CHECK-FIXES: }
+
+int main() {
+  n26::n27::n28::n29::n30::t();
+#ifdef IEXIST
+  n39::n40::t();
+#endif
+
+#ifdef IDONTEXIST
+  n41::n42::t();
+#endif
+
+  return 0;
+}