1 files changed, 84 insertions, 0 deletions
diff --git a/test/clang-tidy/readability-redundant-preprocessor.cpp b/test/clang-tidy/readability-redundant-preprocessor.cpp
new file mode 100644
index 00000000..6cffd8f4
--- /dev/null
+++ b/test/clang-tidy/readability-redundant-preprocessor.cpp
@@ -0,0 +1,84 @@
+// RUN: %check_clang_tidy %s readability-redundant-preprocessor %t -- -- -I %S
+
+// Positive testing.
+#ifndef FOO
+// CHECK-NOTES: [[@LINE+1]]:2: warning: nested redundant #ifndef; consider removing it [readability-redundant-preprocessor]
+#ifndef FOO
+// CHECK-NOTES: [[@LINE-3]]:2: note: previous #ifndef was here
+void f();
+#endif
+#endif
+
+// Positive testing of inverted condition.
+#ifndef FOO
+// CHECK-NOTES: [[@LINE+1]]:2: warning: nested redundant #ifdef; consider removing it [readability-redundant-preprocessor]
+#ifdef FOO
+// CHECK-NOTES: [[@LINE-3]]:2: note: previous #ifndef was here
+void f2();
+#endif
+#endif
+
+// Negative testing.
+#include "readability-redundant-preprocessor.h"
+
+#ifndef BAR
+void g();
+#endif
+
+#ifndef FOO
+#ifndef BAR
+void h();
+#endif
+#endif
+
+#ifndef FOO
+#ifdef BAR
+void i();
+#endif
+#endif
+
+// Positive #if testing.
+#define FOO 4
+
+#if FOO == 4
+// CHECK-NOTES: [[@LINE+1]]:2: warning: nested redundant #if; consider removing it [readability-redundant-preprocessor]
+#if FOO == 4
+// CHECK-NOTES: [[@LINE-3]]:2: note: previous #if was here
+void j();
+#endif
+#endif
+
+#if FOO == 3 + 1
+// CHECK-NOTES: [[@LINE+1]]:2: warning: nested redundant #if; consider removing it [readability-redundant-preprocessor]
+#if FOO == 3 + 1
+// CHECK-NOTES: [[@LINE-3]]:2: note: previous #if was here
+void j();
+#endif
+#endif
+
+#if FOO == \
+    4
+// CHECK-NOTES: [[@LINE+1]]:2: warning: nested redundant #if; consider removing it [readability-redundant-preprocessor]
+#if FOO == \
+    4
+// CHECK-NOTES: [[@LINE-5]]:2: note: previous #if was here
+void j();
+#endif
+#endif
+
+// Negative #if testing.
+#define BAR 4
+
+#if FOO == 4
+#if BAR == 4
+void k();
+#endif
+#endif
+
+#if FOO == \
+    4
+#if BAR == \
+    5
+void k();
+#endif
+#endif