Merge branch 'unintrusive-compose-preedit' into 'master'

Unintrusive compose preedit

See merge request GNOME/gtk!3220

2 files changed, 125 insertions, 3 deletions

diff --git a/gtk/gtkimcontextsimple.c b/gtk/gtkimcontextsimple.c
index b8fec2f384..86e133fc86 100644
--- a/gtk/gtkimcontextsimple.c
+++ b/gtk/gtkimcontextsimple.c
@@ -930,9 +930,99 @@ gtk_im_context_simple_get_preedit_string (GtkIMContext   *context,
       for (i = 0; priv->compose_buffer[i]; i++)
         {
           if (priv->compose_buffer[i] == GDK_KEY_Multi_key)
-            g_string_append_unichar (s, 0x2384); /* U+2384 COMPOSITION SYMBOL */
+            {
+              /* We only show the Compose key visibly when it is the
+               * only glyph in the preedit, or when it occurs in the
+               * middle of the sequence. Sadly, the official character,
+               * U+2384, COMPOSITION SYMBOL, is bit too distracting, so
+               * we use U+00B7, MIDDLE DOT.
+               */
+              if (priv->compose_buffer[1] == 0 || i > 0)
+                g_string_append (s, "·");
+            }
           else
-            g_string_append_unichar (s, gdk_keyval_to_unicode (priv->compose_buffer[i]));
+            {
+              gunichar ch;
+              gboolean need_space;
+
+              if (GDK_KEY_dead_grave <= priv->compose_buffer[i] && priv->compose_buffer[i] <= GDK_KEY_dead_greek)
+                {
+                  /* Sadly, not all the dead keysyms have spacing mark equivalents
+                   * in Unicode. For those that don't, we use space + the non-spacing
+                   * mark as an approximation
+                   */
+                  switch (priv->compose_buffer[i])
+                    {
+#define CASE(keysym, unicode, sp) \
+                    case GDK_KEY_dead_##keysym: ch = unicode; need_space = sp; break
+
+                    CASE (grave, 0x60, 0);
+                    CASE (acute, 0xb4, 0);
+                    CASE (circumflex, 0x5e, 0);
+                    CASE (tilde, 0x7e, 0);
+                    CASE (macron, 0xaf, 0);
+                    CASE (breve, 0x2d8, 0);
+                    CASE (abovedot, 0x307, 1);
+                    CASE (diaeresis, 0xa8, 0);
+                    CASE (abovering, 0x2da, 0);
+                    CASE (hook, 0x2c0, 0);
+                    CASE (doubleacute, 0x2dd, 0);
+                    CASE (caron, 0x2c7, 0);
+                    CASE (cedilla, 0xb8, 0);
+                    CASE (ogonek, 0x2db, 0);
+                    CASE (iota, 0x37a, 0);
+                    CASE (voiced_sound, 0x3099, 1);
+                    CASE (semivoiced_sound, 0x309a, 1);
+                    CASE (belowdot, 0x323, 1);
+                    CASE (horn, 0x31b, 1);
+                    CASE (stroke, 0x335, 1);
+                    CASE (abovecomma, 0x2bc, 0);
+                    CASE (abovereversedcomma, 0x2bd, 1);
+                    CASE (doublegrave, 0x30f, 1);
+                    CASE (belowring, 0x2f3, 0);
+                    CASE (belowmacron, 0x2cd, 0);
+                    CASE (belowcircumflex, 0x32d, 1);
+                    CASE (belowtilde, 0x330, 1);
+                    CASE (belowbreve, 0x32e, 1);
+                    CASE (belowdiaeresis, 0x324, 1);
+                    CASE (invertedbreve, 0x32f, 1);
+                    CASE (belowcomma, 0x326, 1);
+                    CASE (lowline, 0x5f, 0);
+                    CASE (aboveverticalline, 0x2c8, 0);
+                    CASE (belowverticalline, 0x2cc, 0);
+                    CASE (longsolidusoverlay, 0x338, 1);
+                    CASE (a, 0x363, 1);
+                    CASE (A, 0x363, 1);
+                    CASE (e, 0x364, 1);
+                    CASE (E, 0x364, 1);
+                    CASE (i, 0x365, 1);
+                    CASE (I, 0x365, 1);
+                    CASE (o, 0x366, 1);
+                    CASE (O, 0x366, 1);
+                    CASE (u, 0x367, 1);
+                    CASE (U, 0x367, 1);
+                    CASE (small_schwa, 0x1dea, 1);
+                    CASE (capital_schwa, 0x1dea, 1);
+#undef CASE
+                    default:
+                      need_space = FALSE;
+                      ch = gdk_keyval_to_unicode (priv->compose_buffer[i]);
+                      break;
+                    }
+                  if (ch)
+                    {
+                      if (need_space)
+                        g_string_append_c (s, ' ');
+                      g_string_append_unichar (s, ch);
+                    }
+                }
+              else
+                {
+                  ch = gdk_keyval_to_unicode (priv->compose_buffer[i]);
+                  if (ch)
+                    g_string_append_unichar (s, ch);
+                }
+            }
         }
     }
 
diff --git a/gtk/gtkimcontextwayland.c b/gtk/gtkimcontextwayland.c
index 915ad9e854..397909064d 100644
--- a/gtk/gtkimcontextwayland.c
+++ b/gtk/gtkimcontextwayland.c
@@ -570,6 +570,38 @@ gtk_im_context_wayland_set_client_widget (GtkIMContext *context,
     }
 }
 
+/* We want a unified experience between GtkIMContextSimple and IBus / Wayland
+ * when it comes to Compose sequences. IBus initial implementation of preedit
+ * for Compose sequences shows U+2384, which has been described as 'distracting'.
+ * This function tries to detect this case, and tweaks the text to match what
+ * GtkIMContextSimple produces.
+ */
+static char *
+tweak_preedit (const char *text)
+{
+  GString *s;
+  guint len;
+
+  s = g_string_new ("");
+
+  len = g_utf8_strlen (text, -1);
+
+  for (const char *p = text; *p; p = g_utf8_next_char (p))
+    {
+      gunichar ch = g_utf8_get_char (p);
+
+      if (ch == 0x2384)
+        {
+          if (len == 1 || p > text)
+            g_string_append (s, "·");
+        }
+      else
+        g_string_append_unichar (s, ch);
+    }
+
+  return g_string_free (s, FALSE);
+}
+
 static void
 gtk_im_context_wayland_get_preedit_string (GtkIMContext   *context,
                                            char          **str,
@@ -599,7 +631,7 @@ gtk_im_context_wayland_get_preedit_string (GtkIMContext   *context,
     context_wayland->current_preedit.text ? context_wayland->current_preedit.text : "";
 
   if (str)
-    *str = g_strdup (preedit_str);
+    *str = tweak_preedit (preedit_str);
   if (cursor_pos)
     *cursor_pos = g_utf8_strlen (preedit_str,
                                  context_wayland->current_preedit.cursor_begin);