--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/clang/test/Preprocessor/suggest-typoed-directive.c	Wed Nov 09 17:45:10 2022 +0900
@@ -0,0 +1,60 @@
+// RUN: %clang_cc1 -fsyntax-only -verify=pre-c2x-cpp2b %s
+// RUN: %clang_cc1 -std=c2x -fsyntax-only -verify=c2x-cpp2b %s
+// RUN: %clang_cc1 -x c++ -std=c++2b -fsyntax-only -verify=c2x-cpp2b %s
+// RUN: %clang_cc1 -x c++ -std=c++2b -fsyntax-only %s -fdiagnostics-parseable-fixits 2>&1 | FileCheck %s
+
+// id:        pre-c2x-cpp2b-warning@+12 {{invalid preprocessing directive, did you mean '#if'?}}
+// ifd:       pre-c2x-cpp2b-warning@+12 {{invalid preprocessing directive, did you mean '#if'?}}
+// ifde:      pre-c2x-cpp2b-warning@+12 {{invalid preprocessing directive, did you mean '#ifdef'?}}
+// elf:       pre-c2x-cpp2b-warning@+12 {{invalid preprocessing directive, did you mean '#elif'?}}
+// elsif:     pre-c2x-cpp2b-warning@+12 {{invalid preprocessing directive, did you mean '#elif'?}}
+// elseif:    pre-c2x-cpp2b-warning@+12 {{invalid preprocessing directive, did you mean '#elif'?}}
+// elfidef:   not suggested to '#elifdef'
+// elfindef:  not suggested to '#elifdef'
+// elfinndef: not suggested to '#elifndef'
+// els:       pre-c2x-cpp2b-warning@+12 {{invalid preprocessing directive, did you mean '#else'?}}
+// endi:      pre-c2x-cpp2b-warning@+12 {{invalid preprocessing directive, did you mean '#endif'?}}
+#ifdef UNDEFINED
+#id
+#ifd
+#ifde
+# elf
+#  elsif
+#elseif
+#elfidef
+#elfindef
+#elfinndef
+#els
+#endi
+#endif
+// id:        c2x-cpp2b-warning@-12 {{invalid preprocessing directive, did you mean '#if'?}}
+// ifd:       c2x-cpp2b-warning@-12 {{invalid preprocessing directive, did you mean '#if'?}}
+// ifde:      c2x-cpp2b-warning@-12 {{invalid preprocessing directive, did you mean '#ifdef'?}}
+// elf:       c2x-cpp2b-warning@-12 {{invalid preprocessing directive, did you mean '#elif'?}}
+// elsif:     c2x-cpp2b-warning@-12 {{invalid preprocessing directive, did you mean '#elif'?}}
+// elseif:    c2x-cpp2b-warning@-12 {{invalid preprocessing directive, did you mean '#elif'?}}
+// elfidef:   c2x-cpp2b-warning@-12 {{invalid preprocessing directive, did you mean '#elifdef'?}}
+// elfindef:  c2x-cpp2b-warning@-12 {{invalid preprocessing directive, did you mean '#elifdef'?}}
+// elfinndef: c2x-cpp2b-warning@-12 {{invalid preprocessing directive, did you mean '#elifndef'?}}
+// els:       c2x-cpp2b-warning@-12 {{invalid preprocessing directive, did you mean '#else'?}}
+// endi:      c2x-cpp2b-warning@-12 {{invalid preprocessing directive, did you mean '#endif'?}}
+
+// CHECK: fix-it:{{.*}}:{[[@LINE-24]]:2-[[@LINE-24]]:4}:"if"
+// CHECK: fix-it:{{.*}}:{[[@LINE-24]]:2-[[@LINE-24]]:5}:"if"
+// CHECK: fix-it:{{.*}}:{[[@LINE-24]]:2-[[@LINE-24]]:6}:"ifdef"
+// CHECK: fix-it:{{.*}}:{[[@LINE-24]]:3-[[@LINE-24]]:6}:"elif"
+// CHECK: fix-it:{{.*}}:{[[@LINE-24]]:4-[[@LINE-24]]:9}:"elif"
+// CHECK: fix-it:{{.*}}:{[[@LINE-24]]:2-[[@LINE-24]]:8}:"elif"
+// CHECK: fix-it:{{.*}}:{[[@LINE-24]]:2-[[@LINE-24]]:9}:"elifdef"
+// CHECK: fix-it:{{.*}}:{[[@LINE-24]]:2-[[@LINE-24]]:10}:"elifdef"
+// CHECK: fix-it:{{.*}}:{[[@LINE-24]]:2-[[@LINE-24]]:11}:"elifndef"
+// CHECK: fix-it:{{.*}}:{[[@LINE-24]]:2-[[@LINE-24]]:5}:"else"
+// CHECK: fix-it:{{.*}}:{[[@LINE-24]]:2-[[@LINE-24]]:6}:"endif"
+
+#ifdef UNDEFINED
+#i // no diagnostic
+#endif
+
+#if special_compiler
+#special_compiler_directive // no diagnostic
+#endif