build: allow IWYU to fix includes for all .c files

Allow Include What You Use to remove unnecessary includes and only
include what is necessary. This helps with reducing compilation times
and makes it easier to visualise which dependencies are actually
required.

Work on https://github.com/neovim/neovim/issues/549, but doesn't close
it since this only works fully for .c files and not headers.

7 files changed, 73 insertions, 46 deletions

diff --git a/src/nvim/lua/converter.c b/src/nvim/lua/converter.c
index d7881350aa..3c129fe7ce 100644
--- a/src/nvim/lua/converter.c
+++ b/src/nvim/lua/converter.c
@@ -4,14 +4,14 @@
 #include <assert.h>
 #include <lauxlib.h>
 #include <lua.h>
-#include <lualib.h>
 #include <stdbool.h>
+#include <stddef.h>
 #include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
 
 #include "nvim/api/private/defs.h"
 #include "nvim/api/private/helpers.h"
-#include "nvim/assert.h"
-#include "nvim/func_attr.h"
 #include "nvim/memory.h"
 // FIXME: vim.h is not actually needed, but otherwise it states MAXPATHL is
 //        redefined
@@ -19,12 +19,16 @@
 #include "nvim/ascii.h"
 #include "nvim/eval/decode.h"
 #include "nvim/eval/typval.h"
+#include "nvim/eval/typval_defs.h"
+#include "nvim/eval/typval_encode.h"
 #include "nvim/eval/userfunc.h"
-#include "nvim/globals.h"
+#include "nvim/garray.h"
+#include "nvim/gettext.h"
 #include "nvim/lua/converter.h"
 #include "nvim/lua/executor.h"
 #include "nvim/macros.h"
 #include "nvim/message.h"
+#include "nvim/types.h"
 #include "nvim/vim.h"
 
 /// Determine, which keys lua table contains
@@ -565,6 +569,7 @@ static bool typval_conv_special = false;
 #define TYPVAL_ENCODE_FIRST_ARG_TYPE lua_State *const
 #define TYPVAL_ENCODE_FIRST_ARG_NAME lstate
 #include "nvim/eval/typval_encode.c.h"
+
 #undef TYPVAL_ENCODE_SCOPE
 #undef TYPVAL_ENCODE_NAME
 #undef TYPVAL_ENCODE_FIRST_ARG_TYPE
diff --git a/src/nvim/lua/executor.c b/src/nvim/lua/executor.c
index 9cb42a81d3..d2c2f932ec 100644
--- a/src/nvim/lua/executor.c
+++ b/src/nvim/lua/executor.c
@@ -1,18 +1,22 @@
 // This is an open source non-commercial project. Dear PVS-Studio, please check
 // it. PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
 
+#include <assert.h>
+#include <inttypes.h>
 #include <lauxlib.h>
 #include <lua.h>
 #include <lualib.h>
+#include <stddef.h>
+#include <string.h>
 #include <tree_sitter/api.h>
+#include <uv.h>
 
+#include "klib/kvec.h"
 #include "luv/luv.h"
 #include "nvim/api/extmark.h"
 #include "nvim/api/private/defs.h"
 #include "nvim/api/private/helpers.h"
-#include "nvim/api/vim.h"
 #include "nvim/ascii.h"
-#include "nvim/assert.h"
 #include "nvim/buffer_defs.h"
 #include "nvim/change.h"
 #include "nvim/cursor.h"
@@ -20,28 +24,37 @@
 #include "nvim/eval.h"
 #include "nvim/eval/funcs.h"
 #include "nvim/eval/typval.h"
+#include "nvim/eval/typval_defs.h"
 #include "nvim/eval/userfunc.h"
+#include "nvim/event/defs.h"
 #include "nvim/event/loop.h"
+#include "nvim/event/multiqueue.h"
 #include "nvim/event/time.h"
 #include "nvim/ex_cmds.h"
+#include "nvim/ex_cmds_defs.h"
 #include "nvim/ex_getln.h"
-#include "nvim/extmark.h"
-#include "nvim/func_attr.h"
 #include "nvim/garray.h"
 #include "nvim/getchar.h"
+#include "nvim/gettext.h"
+#include "nvim/globals.h"
+#include "nvim/keycodes.h"
 #include "nvim/lua/converter.h"
 #include "nvim/lua/executor.h"
 #include "nvim/lua/stdlib.h"
 #include "nvim/lua/treesitter.h"
 #include "nvim/macros.h"
-#include "nvim/map.h"
+#include "nvim/main.h"
 #include "nvim/memline.h"
+#include "nvim/memory.h"
 #include "nvim/message.h"
 #include "nvim/msgpack_rpc/channel.h"
+#include "nvim/option_defs.h"
 #include "nvim/os/os.h"
+#include "nvim/path.h"
+#include "nvim/pos.h"
 #include "nvim/profile.h"
 #include "nvim/runtime.h"
-#include "nvim/screen.h"
+#include "nvim/strings.h"
 #include "nvim/ui.h"
 #include "nvim/ui_compositor.h"
 #include "nvim/undo.h"
diff --git a/src/nvim/lua/executor.h b/src/nvim/lua/executor.h
index 78346fd81f..c6747833e5 100644
--- a/src/nvim/lua/executor.h
+++ b/src/nvim/lua/executor.h
@@ -3,13 +3,17 @@
 
 #include <lauxlib.h>
 #include <lua.h>
+#include <stdbool.h>
 
 #include "nvim/api/private/defs.h"
+#include "nvim/api/private/helpers.h"
 #include "nvim/assert.h"
 #include "nvim/eval/typval.h"
 #include "nvim/ex_cmds_defs.h"
 #include "nvim/func_attr.h"
 #include "nvim/lua/converter.h"
+#include "nvim/macros.h"
+#include "nvim/types.h"
 #include "nvim/usercmd.h"
 
 // Generated by msgpack-gen.lua
diff --git a/src/nvim/lua/spell.c b/src/nvim/lua/spell.c
index 31a2b2d19f..0a566b2f86 100644
--- a/src/nvim/lua/spell.c
+++ b/src/nvim/lua/spell.c
@@ -1,15 +1,25 @@
 // This is an open source non-commercial project. Dear PVS-Studio, please check
 // it. PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
 
+#include <assert.h>
 #include <lauxlib.h>
+#include <limits.h>
 #include <lua.h>
-
+#include <stdbool.h>
+#include <stddef.h>
+
+#include "nvim/ascii.h"
+#include "nvim/buffer_defs.h"
+#include "nvim/gettext.h"
+#include "nvim/globals.h"
+#include "nvim/highlight_defs.h"
 #include "nvim/lua/spell.h"
+#include "nvim/message.h"
 #include "nvim/spell.h"
-#include "nvim/vim.h"
+#include "nvim/types.h"
 
 #ifdef INCLUDE_GENERATED_DECLARATIONS
-# include "lua/spell.c.generated.h"
+# include "lua/spell.c.generated.h"  // IWYU pragma: export
 #endif
 
 int nlua_spell_check(lua_State *lstate)
diff --git a/src/nvim/lua/stdlib.c b/src/nvim/lua/stdlib.c
index 54e2c24523..813f86eeee 100644
--- a/src/nvim/lua/stdlib.c
+++ b/src/nvim/lua/stdlib.c
@@ -1,50 +1,39 @@
 // This is an open source non-commercial project. Dear PVS-Studio, please check
 // it. PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
 
+#include <assert.h>
 #include <lauxlib.h>
 #include <lua.h>
-#include <lualib.h>
-
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include "auto/config.h"
 #include "cjson/lua_cjson.h"
-#include "luv/luv.h"
 #include "mpack/lmpack.h"
 #include "nvim/api/private/defs.h"
 #include "nvim/api/private/helpers.h"
-#include "nvim/api/vim.h"
 #include "nvim/ascii.h"
-#include "nvim/assert.h"
 #include "nvim/buffer_defs.h"
-#include "nvim/change.h"
-#include "nvim/cursor.h"
 #include "nvim/eval.h"
-#include "nvim/eval/userfunc.h"
-#include "nvim/event/loop.h"
-#include "nvim/event/time.h"
+#include "nvim/eval/typval.h"
+#include "nvim/eval/typval_defs.h"
 #include "nvim/ex_eval.h"
-#include "nvim/ex_getln.h"
-#include "nvim/extmark.h"
-#include "nvim/func_attr.h"
-#include "nvim/garray.h"
-#include "nvim/getchar.h"
 #include "nvim/globals.h"
 #include "nvim/lua/converter.h"
-#include "nvim/lua/executor.h"
 #include "nvim/lua/spell.h"
 #include "nvim/lua/stdlib.h"
-#include "nvim/lua/treesitter.h"
 #include "nvim/lua/xdiff.h"
-#include "nvim/macros.h"
 #include "nvim/map.h"
+#include "nvim/mbyte.h"
 #include "nvim/memline.h"
-#include "nvim/message.h"
-#include "nvim/msgpack_rpc/channel.h"
-#include "nvim/os/os.h"
+#include "nvim/memory.h"
+#include "nvim/pos.h"
 #include "nvim/regexp.h"
-#include "nvim/regexp_defs.h"
-#include "nvim/screen.h"
 #include "nvim/types.h"
-#include "nvim/undo.h"
-#include "nvim/version.h"
 #include "nvim/vim.h"
 
 #ifdef INCLUDE_GENERATED_DECLARATIONS
diff --git a/src/nvim/lua/treesitter.c b/src/nvim/lua/treesitter.c
index 9d871939f8..d77e210c6a 100644
--- a/src/nvim/lua/treesitter.c
+++ b/src/nvim/lua/treesitter.c
@@ -6,23 +6,28 @@
 // trees and nodes, and could be broken out as a reusable lua package
 
 #include <assert.h>
-#include <inttypes.h>
 #include <lauxlib.h>
+#include <limits.h>
 #include <lua.h>
-#include <lualib.h>
 #include <stdbool.h>
 #include <stdint.h>
+#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <uv.h>
 
 #include "klib/kvec.h"
 #include "nvim/api/private/helpers.h"
-#include "nvim/buffer.h"
-#include "nvim/log.h"
+#include "nvim/buffer_defs.h"
+#include "nvim/globals.h"
 #include "nvim/lua/treesitter.h"
+#include "nvim/macros.h"
 #include "nvim/map.h"
 #include "nvim/memline.h"
+#include "nvim/memory.h"
+#include "nvim/pos.h"
+#include "nvim/strings.h"
+#include "nvim/types.h"
 #include "tree_sitter/api.h"
 
 #define TS_META_PARSER "treesitter_parser"
diff --git a/src/nvim/lua/xdiff.c b/src/nvim/lua/xdiff.c
index cd542b0e00..857b159af5 100644
--- a/src/nvim/lua/xdiff.c
+++ b/src/nvim/lua/xdiff.c
@@ -1,19 +1,20 @@
 // This is an open source non-commercial project. Dear PVS-Studio, please check
 // it. PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
 
-#include <errno.h>
 #include <lauxlib.h>
 #include <lua.h>
-#include <lualib.h>
-#include <stdio.h>
-#include <stdlib.h>
+#include <stdbool.h>
 #include <string.h>
 
+#include "luaconf.h"
+#include "nvim/api/private/defs.h"
 #include "nvim/api/private/helpers.h"
 #include "nvim/linematch.h"
 #include "nvim/lua/converter.h"
 #include "nvim/lua/executor.h"
 #include "nvim/lua/xdiff.h"
+#include "nvim/macros.h"
+#include "nvim/memory.h"
 #include "nvim/vim.h"
 #include "xdiff/xdiff.h"