diff --git a/source/blender/blenkernel/BKE_vfont.h b/source/blender/blenkernel/BKE_vfont.h
index aea662d6548..e3a7e07de97 100644
--- a/source/blender/blenkernel/BKE_vfont.h
+++ b/source/blender/blenkernel/BKE_vfont.h
@@ -98,6 +98,10 @@ void BKE_vfont_clipboard_get(char32_t **r_text_buf,
                              size_t *r_len_utf8,
                              size_t *r_len_utf32);
 
+/* Declared in `bpy_interface.c` */
+int text_toupper_unicode(const unsigned int ch);
+int text_tolower_unicode(const unsigned int ch);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/source/blender/editors/curve/CMakeLists.txt b/source/blender/editors/curve/CMakeLists.txt
index 6b46c822e86..18fbb3c3d0c 100644
--- a/source/blender/editors/curve/CMakeLists.txt
+++ b/source/blender/editors/curve/CMakeLists.txt
@@ -41,6 +41,9 @@ set(LIB
   extern_curve_fit_nd
 )
 
+if(WITH_PYTHON)
+  add_definitions(-DWITH_PYTHON)
+endif()
 
 blender_add_lib(bf_editor_curve "${SRC}" "${INC}" "${INC_SYS}" "${LIB}")
 
diff --git a/source/blender/editors/curve/editfont.c b/source/blender/editors/curve/editfont.c
index f96bb85d53e..6a28c04913c 100644
--- a/source/blender/editors/curve/editfont.c
+++ b/source/blender/editors/curve/editfont.c
@@ -1982,23 +1982,26 @@ static int set_case(bContext *C, int ccase)
     len = (selend - selstart) + 1;
     str = &ef->textbuf[selstart];
     while (len) {
-      if (*str >= 'a' && *str <= 'z') {
-        *str -= 32;
-      }
-      len--;
-      str++;
-    }
-
-    if (ccase == CASE_LOWER) {
-      len = (selend - selstart) + 1;
-      str = &ef->textbuf[selstart];
-      while (len) {
+      if (ccase == CASE_LOWER) {
+#ifdef WITH_PYTHON
+        *str = text_tolower_unicode(*str);
+#else
         if (*str >= 'A' && *str <= 'Z') {
           *str += 32;
         }
-        len--;
-        str++;
+#endif
       }
+      else {
+#ifdef WITH_PYTHON
+        *str = text_toupper_unicode(*str);
+#else
+        if (*str >= 'a' && *str <= 'z') {
+          *str -= 32;
+        }
+#endif
+      }
+      len--;
+      str++;
     }
 
     text_update_edited(C, obedit, FO_EDIT);
diff --git a/source/blender/python/intern/bpy_interface.c b/source/blender/python/intern/bpy_interface.c
index 4fe39e1c5b0..9f5469e1564 100644
--- a/source/blender/python/intern/bpy_interface.c
+++ b/source/blender/python/intern/bpy_interface.c
@@ -46,6 +46,7 @@
 #include "BKE_global.h" /* only for script checking */
 #include "BKE_main.h"
 #include "BKE_text.h"
+#include "BKE_vfont.h" /* For `text_toupper_unicode` declaration. */
 
 #ifdef WITH_CYCLES
 #  include "CCL_api.h"
@@ -956,3 +957,14 @@ int text_check_identifier_nodigit_unicode(const uint ch)
 {
   return (ch < 255 && text_check_identifier_nodigit((char)ch)) || Py_UNICODE_ISALPHA(ch);
 }
+
+/* EVIL: define `editfont.c` functions here (declared in `BKE_vfont.h`). */
+int text_toupper_unicode(const uint ch)
+{
+  return Py_UNICODE_TOUPPER(ch);
+}
+
+int text_tolower_unicode(const uint ch)
+{
+  return Py_UNICODE_TOLOWER(ch);
+}