[core] enable ghpa only on kitty for now #2199

src/lib/internal.h

@@ -1166,7 +1166,7 @@ goto_location(notcurses* nc, fbuf* f, int y, int x, const ncplane* srcp){
   const char* hpa = get_escape(&nc->tcache, ESCAPE_HPA);
   if(nc->rstate.y == y && hpa && !nc->rstate.hardcursorpos){ // only need move x
     if(nc->rstate.x == x){
-      if(nc->rstate.lastsrcp == srcp){
+      if(nc->rstate.lastsrcp == srcp || !nc->tcache.gratuitous_hpa){
         return 0; // needn't move shit
       }
       ++nc->stats.s.hpa_gratuitous;

src/lib/termdesc.c

@@ -585,6 +585,7 @@ apply_term_heuristics(tinfo* ti, const char* termname, queried_terminals_e qterm
     // kitty SUM doesn't want long sequences, which is exactly where we use
     // it. remove support (we pick it up from queries).
     kill_appsync_escapes(ti);
+    ti->gratuitous_hpa = true;
   }else if(qterm == TERMINAL_ALACRITTY){
     termname = "Alacritty";
     ti->caps.quadrants = true;

src/lib/termdesc.h

@@ -167,6 +167,8 @@ typedef struct tinfo {
   struct termios *tpreserved;// terminal state upon entry
   struct inputctx* ictx;     // new input layer
   unsigned stdio_blocking_save; // was stdio blocking at entry? restore on stop.
+  // ought we issue gratuitous HPAs to work around ambiguous widths?
+  unsigned gratuitous_hpa;
 
   // if we get a reply to our initial \e[18t cell geometry query, it will
   // replace these values. note that LINES/COLUMNS cannot be used to limit