From c202be1efea1a4e9b7f6042b892a2d6a5c2c220f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Hubert=20G=C5=82uchowski?= <fishhh@fishhh.dev>
Date: Sun, 19 Apr 2026 21:19:56 +0200
Subject: [PATCH] player/{lua,javascript}: add
 `mp.utils.terminal_display_width` function

---
 .../mp-utils-terminal-display-width.txt               |  2 ++
 player/javascript.c                                   | 11 +++++++++++
 player/lua.c                                          | 11 +++++++++++
 3 files changed, 24 insertions(+)
 create mode 100644 DOCS/interface-changes/mp-utils-terminal-display-width.txt

diff --git a/DOCS/interface-changes/mp-utils-terminal-display-width.txt b/DOCS/interface-changes/mp-utils-terminal-display-width.txt
new file mode 100644
index 0000000000..812bf7a911
--- /dev/null
+++ b/DOCS/interface-changes/mp-utils-terminal-display-width.txt
@@ -0,0 +1,2 @@
+add `mp.utils.terminal_display_width()` function that measures the width of
+a string in terminal cells
diff --git a/player/javascript.c b/player/javascript.c
index ae8fe37969..a573cba0df 100644
--- a/player/javascript.c
+++ b/player/javascript.c
@@ -35,6 +35,7 @@
 #include "input/input.h"
 #include "options/path.h"
 #include "misc/bstr.h"
+#include "misc/codepoint_width.h"
 #include "osdep/timer.h"
 #include "osdep/threads.h"
 #include "stream/stream.h"
@@ -1000,6 +1001,15 @@ static void script_get_env_list(js_State *J)
     }
 }
 
+// args: text
+static void script_terminal_display_width(js_State *J)
+{
+    bstr text = bstr0(js_tostring(J, 1));
+    const unsigned char *cut_pos;
+    int width = term_disp_width(text, INT_MAX, &cut_pos);
+    js_pushnumber(J, width);
+}
+
 // args: as-filename, content-string, returns the compiled result as a function
 static void script_compile_js(js_State *J)
 {
@@ -1202,6 +1212,7 @@ static const struct fn_entry utils_fns[] = {
     FN_ENTRY(split_path, 1),
     AF_ENTRY(join_path, 2),
     FN_ENTRY(get_env_list, 0),
+    FN_ENTRY(terminal_display_width, 1),
 
     FN_ENTRY(read_file, 2),
     AF_ENTRY(_write_file, 3),
diff --git a/player/lua.c b/player/lua.c
index b37aac941f..d2b6b9e6d8 100644
--- a/player/lua.c
+++ b/player/lua.c
@@ -38,6 +38,7 @@
 #include "input/input.h"
 #include "options/path.h"
 #include "misc/bstr.h"
+#include "misc/codepoint_width.h"
 #include "misc/json.h"
 #include "osdep/subprocess.h"
 #include "osdep/timer.h"
@@ -1216,6 +1217,15 @@ static int script_get_env_list(lua_State *L)
     return 1;
 }
 
+static int script_terminal_display_width(lua_State *L)
+{
+    bstr text = bstr0(luaL_checkstring(L, 1));
+    const unsigned char *cut_pos;
+    int width = term_disp_width(text, INT_MAX, &cut_pos);
+    lua_pushnumber(L, width);
+    return 1;
+}
+
 #define FN_ENTRY(name) {#name, script_ ## name, 0}
 #define AF_ENTRY(name) {#name, 0, script_ ## name}
 struct fn_entry {
@@ -1265,6 +1275,7 @@ static const struct fn_entry utils_fns[] = {
     AF_ENTRY(parse_json),
     AF_ENTRY(format_json),
     FN_ENTRY(get_env_list),
+    FN_ENTRY(terminal_display_width),
     {0}
 };