refactor: run IWYU on entire repo

Reference: https://github.com/neovim/neovim/issues/6371.

120 files changed, 308 insertions, 418 deletions

diff --git a/src/clint.py b/src/clint.py
index 80ebf565a1..303c3df25d 100755
--- a/src/clint.py
+++ b/src/clint.py
@@ -897,8 +897,6 @@ def CheckIncludes(filename, lines, error):
     }):
         return
 
-    # These should be synced with the ignored headers in the `iwyu` target in
-    # the Makefile.
     check_includes_ignore = [
             "src/nvim/api/private/validate.h",
             "src/nvim/assert_defs.h",
@@ -913,6 +911,7 @@ def CheckIncludes(filename, lines, error):
             "src/nvim/eval/userfunc.h",
             "src/nvim/event/libuv_process.h",
             "src/nvim/event/loop.h",
+            "src/nvim/event/multiqueue.h",
             "src/nvim/event/process.h",
             "src/nvim/event/rstream.h",
             "src/nvim/event/signal.h",
@@ -928,6 +927,7 @@ def CheckIncludes(filename, lines, error):
             "src/nvim/keycodes.h",
             "src/nvim/lua/executor.h",
             "src/nvim/main.h",
+            "src/nvim/mark.h",
             "src/nvim/msgpack_rpc/channel_defs.h",
             "src/nvim/msgpack_rpc/helpers.h",
             "src/nvim/msgpack_rpc/unpacker.h",
diff --git a/src/nvim/api/private/converter.h b/src/nvim/api/private/converter.h
index fc82abf332..a5acc56c7c 100644
--- a/src/nvim/api/private/converter.h
+++ b/src/nvim/api/private/converter.h
@@ -1,6 +1,6 @@
 #pragma once
 
-#include "nvim/api/private/defs.h"  // IWYU pragma: keep
+#include "nvim/api/private/defs.h"  // IWYU pragma: export
 #include "nvim/eval/typval_defs.h"  // IWYU pragma: keep
 
 #ifdef INCLUDE_GENERATED_DECLARATIONS
diff --git a/src/nvim/api/private/dispatch.h b/src/nvim/api/private/dispatch.h
index b627db6b00..d322c1ceca 100644
--- a/src/nvim/api/private/dispatch.h
+++ b/src/nvim/api/private/dispatch.h
@@ -3,7 +3,7 @@
 #include <stdbool.h>
 #include <stdint.h>
 
-#include "nvim/api/private/defs.h"
+#include "nvim/api/private/defs.h"  // IWYU pragma: export
 #include "nvim/memory_defs.h"
 #include "nvim/types_defs.h"
 
diff --git a/src/nvim/api/private/helpers.h b/src/nvim/api/private/helpers.h
index 701ce91257..1ee66f906b 100644
--- a/src/nvim/api/private/helpers.h
+++ b/src/nvim/api/private/helpers.h
@@ -4,7 +4,7 @@
 #include <stddef.h>
 
 #include "klib/kvec.h"
-#include "nvim/api/private/defs.h"
+#include "nvim/api/private/defs.h"  // IWYU pragma: export
 #include "nvim/buffer_defs.h"  // IWYU pragma: keep
 #include "nvim/eval/typval_defs.h"  // IWYU pragma: keep
 #include "nvim/ex_eval_defs.h"
diff --git a/src/nvim/api/private/validate.h b/src/nvim/api/private/validate.h
index d1c977cd6e..692ea46176 100644
--- a/src/nvim/api/private/validate.h
+++ b/src/nvim/api/private/validate.h
@@ -3,7 +3,7 @@
 #include <stdbool.h>
 #include <stddef.h>
 
-#include "nvim/api/private/defs.h"
+#include "nvim/api/private/defs.h"  // IWYU pragma: export
 #include "nvim/api/private/helpers.h"
 #include "nvim/assert_defs.h"
 #include "nvim/macros_defs.h"
diff --git a/src/nvim/api/ui.c b/src/nvim/api/ui.c
index 678d23fbeb..82d42d652d 100644
--- a/src/nvim/api/ui.c
+++ b/src/nvim/api/ui.c
@@ -15,7 +15,8 @@
 #include "nvim/autocmd.h"
 #include "nvim/channel.h"
 #include "nvim/eval.h"
-#include "nvim/event/defs.h"
+#include "nvim/event/loop.h"
+#include "nvim/event/multiqueue.h"
 #include "nvim/event/wstream.h"
 #include "nvim/globals.h"
 #include "nvim/grid.h"
diff --git a/src/nvim/api/vim.c b/src/nvim/api/vim.c
index 9ae5244fa1..aed286165a 100644
--- a/src/nvim/api/vim.c
+++ b/src/nvim/api/vim.c
@@ -64,6 +64,7 @@
 #include "nvim/statusline.h"
 #include "nvim/strings.h"
 #include "nvim/terminal.h"
+#include "nvim/types_defs.h"
 #include "nvim/ui.h"
 #include "nvim/vim_defs.h"
 #include "nvim/window.h"
diff --git a/src/nvim/ascii_defs.h b/src/nvim/ascii_defs.h
index 3de04cd9fa..4215157654 100644
--- a/src/nvim/ascii_defs.h
+++ b/src/nvim/ascii_defs.h
@@ -86,35 +86,6 @@
 static inline bool ascii_iswhite(int c)
   REAL_FATTR_CONST
   REAL_FATTR_ALWAYS_INLINE;
-
-static inline bool ascii_iswhite_or_nul(int c)
-  REAL_FATTR_CONST
-  REAL_FATTR_ALWAYS_INLINE;
-
-static inline bool ascii_isdigit(int c)
-  REAL_FATTR_CONST
-  REAL_FATTR_ALWAYS_INLINE;
-
-static inline bool ascii_isxdigit(int c)
-  REAL_FATTR_CONST
-  REAL_FATTR_ALWAYS_INLINE;
-
-static inline bool ascii_isident(int c)
-  REAL_FATTR_CONST
-  REAL_FATTR_ALWAYS_INLINE;
-
-static inline bool ascii_isbdigit(int c)
-  REAL_FATTR_CONST
-  REAL_FATTR_ALWAYS_INLINE;
-
-static inline bool ascii_isodigit(int c)
-  REAL_FATTR_CONST
-  REAL_FATTR_ALWAYS_INLINE;
-
-static inline bool ascii_isspace(int c)
-  REAL_FATTR_CONST
-  REAL_FATTR_ALWAYS_INLINE;
-
 /// Checks if `c` is a space or tab character.
 ///
 /// @see {ascii_isdigit}
@@ -123,6 +94,9 @@ static inline bool ascii_iswhite(int c)
   return c == ' ' || c == '\t';
 }
 
+static inline bool ascii_iswhite_or_nul(int c)
+  REAL_FATTR_CONST
+  REAL_FATTR_ALWAYS_INLINE;
 /// Checks if `c` is a space or tab character or NUL.
 ///
 /// @see {ascii_isdigit}
@@ -131,6 +105,9 @@ static inline bool ascii_iswhite_or_nul(int c)
   return ascii_iswhite(c) || c == NUL;
 }
 
+static inline bool a