All platforms use same code to remove context-dependent codepoints from text input.

This commit introduces function fl_utf8_remove_context_dependent() that removes
from an UTF-8 string its context-dependent codepoints. Platforms macOS, Wayland
and X11 call this function to process UTF-8 text received from a character palette
as input to FLTK text. This makes sure FLTK text-editing widgets process textual input
equally and consistently across platforms, especially emojis entered via a palette.

Platform Windows creates a series of separate system events to input an emoji
via the character palette. For this reason, function fl_utf8_remove_context_dependent()
is not used by this platform which does internally the same filtering of context-
dependent codepoints.

1 files changed, 2 insertions, 0 deletions

diff --git a/src/drivers/Wayland/Fl_Wayland_Screen_Driver.cxx b/src/drivers/Wayland/Fl_Wayland_Screen_Driver.cxx
index c474867d5..3816dff2c 100644
--- a/src/drivers/Wayland/Fl_Wayland_Screen_Driver.cxx
+++ b/src/drivers/Wayland/Fl_Wayland_Screen_Driver.cxx
@@ -53,6 +53,7 @@ extern "C" {
   bool fl_is_surface_from_GTK_titlebar (struct wl_surface *surface, struct libdecor_frame *frame,
                                         bool *using_GTK);
 }
+extern int fl_utf8_remove_context_dependent(char *text, int len);
 
 // set this to 1 for keyboard debug output, 0 for no debug output
 #define DEBUG_KEYBOARD 0
@@ -1017,6 +1018,7 @@ void text_input_commit_string(void *data, struct zwp_text_input_v3 *zwp_text_inp
 //printf("text_input_commit_string %s\n",text);
   free(pending_commit);
   pending_commit = text ? strdup(text) : NULL;
+  fl_utf8_remove_context_dependent(pending_commit, strlen(pending_commit));
 }