InputText: move to next word OS X style behavior on OS X (#473)

imgui.cpp

@@ -7097,8 +7097,18 @@ static void    STB_TEXTEDIT_LAYOUTROW(StbTexteditRow* r, STB_TEXTEDIT_STRING* ob
     r->num_chars = (int)(text_remaining - (text + line_start_idx));
 }
 
-static bool is_separator(unsigned int c)                                                          { return c==',' || c==';' || c=='(' || c==')' || c=='{' || c=='}' || c=='[' || c==']' || c=='|'; }
-#define STB_TEXTEDIT_IS_SPACE(CH)                                                                 ( ImCharIsSpace((unsigned int)CH) || is_separator((unsigned int)CH) )
+static bool is_separator(unsigned int c)                                        { return ImCharIsSpace(c) || c==',' || c==';' || c=='(' || c==')' || c=='{' || c=='}' || c=='[' || c==']' || c=='|'; }
+static int  is_word_boundary_from_right(STB_TEXTEDIT_STRING* obj, int idx)      { return idx > 0 ? (is_separator( obj->Text[idx-1] ) && !is_separator( obj->Text[idx] ) ) : 1; }
+static int  is_word_boundary_from_left(STB_TEXTEDIT_STRING* obj, int idx)       { return idx > 0 ? (!is_separator( obj->Text[idx-1] ) && is_separator( obj->Text[idx] ) ) : 1; }
+static int  STB_TEXTEDIT_MOVEWORDLEFT_IMPL(STB_TEXTEDIT_STRING* obj, int idx)   { while (idx >= 0 && !is_word_boundary_from_right(obj, idx)) idx--; return idx < 0 ? 0 : idx; }
+#ifdef __APPLE__    // FIXME: Move setting to IO structure
+static int  STB_TEXTEDIT_MOVEWORDRIGHT_IMPL(STB_TEXTEDIT_STRING* obj, int idx)  { int len = obj->CurLenW; while (idx < len && !is_word_boundary_from_left(obj, idx)) idx++; return idx > len ? len : idx; }
+#else
+static int  STB_TEXTEDIT_MOVEWORDRIGHT_IMPL(STB_TEXTEDIT_STRING* obj, int idx)  { int len = obj->CurLenW; while (idx < len && !is_word_boundary_from_right(obj, idx)) idx++; return idx > len ? len : idx; }
+#endif
+#define STB_TEXTEDIT_MOVEWORDLEFT   STB_TEXTEDIT_MOVEWORDLEFT_IMPL    // They need to be #define for stb_textedit.h
+#define STB_TEXTEDIT_MOVEWORDRIGHT  STB_TEXTEDIT_MOVEWORDRIGHT_IMPL
+
 static void STB_TEXTEDIT_DELETECHARS(STB_TEXTEDIT_STRING* obj, int pos, int n)
 {
     ImWchar* dst = obj->Text.Data + pos;