diff --git a/src/bin/termiointernals.c b/src/bin/termiointernals.c
index 270faa52..cdc0c103 100644
--- a/src/bin/termiointernals.c
+++ b/src/bin/termiointernals.c
@@ -2,13 +2,13 @@
 
 #include <Elementary.h>
 
-#include "tytest.h"
 #include "termio.h"
 #include "miniview.h"
 #include "termpty.h"
 #include "termptyops.h"
 #include "termiointernals.h"
 #include "utf8.h"
+#include "tytest.h"
 
 /* {{{ Selection */
 
diff --git a/src/bin/termptyesc.c b/src/bin/termptyesc.c
index 6edd601f..f6d43d1d 100644
--- a/src/bin/termptyesc.c
+++ b/src/bin/termptyesc.c
@@ -1,6 +1,7 @@
 #include "private.h"
 #include <Elementary.h>
 #include <stdint.h>
+#include <assert.h>
 #include "col.h"
 #include "termio.h"
 #include "termpty.h"
@@ -3750,35 +3751,42 @@ _handle_esc_terminology(Termpty *ty, const Eina_Unicode *c, const Eina_Unicode *
    Eina_Unicode *cc, *cc_zero = NULL;
    const Eina_Unicode *buf;
    char *cmd;
-   int blen = 0;
+   size_t blen = 0;
    Config *config;
 
-   if (!ty->buf_have_zero) return 0;
+   if (!ty->buf_have_zero)
+     return 0;
 
    config = termio_config_get(ty->obj);
 
    cc = (Eina_Unicode *)c;
-   if ((cc < ce) && (*cc == 0x0)) cc_zero = cc;
+   if ((cc < ce) && (*cc == 0x0))
+     cc_zero = cc;
    while ((cc < ce) && (*cc != 0x0))
      {
         blen++;
         cc++;
      }
-   if ((cc < ce) && (*cc == 0x0)) cc_zero = cc;
-   if (!cc_zero) return 0;
+   if ((cc < ce) && (*cc == 0x0))
+     cc_zero = cc;
+   if (!cc_zero)
+     return 0;
    buf = (Eina_Unicode *)c;
    cc = cc_zero;
 
    // commands are stored in the buffer, 0 bytes not allowed (end marker)
    cmd = eina_unicode_unicode_to_utf8(buf, NULL);
    ty->cur_cmd = cmd;
-   if ((!config->ty_escapes) || (!_termpty_ext_handle(ty, cmd, buf)))
+   if ((!config->ty_escapes) || (!termpty_ext_handle(ty, buf, blen)))
      {
-        if (ty->cb.command.func) ty->cb.command.func(ty->cb.command.data);
+        if (ty->cb.command.func)
+          ty->cb.command.func(ty->cb.command.data);
      }
    ty->cur_cmd = NULL;
    free(cmd);
 
+   assert((size_t)(cc - c) == blen);
+
    return cc - c;
 }
 
diff --git a/src/bin/termptyext.c b/src/bin/termptyext.c
index e059f251..888e8403 100644
--- a/src/bin/termptyext.c
+++ b/src/bin/termptyext.c
@@ -2,6 +2,8 @@
 #include <Elementary.h>
 #include "termpty.h"
 #include "termptyops.h"
+#include "tytest.h"
+#include <assert.h>
 
 #undef CRITICAL
 #undef ERR
@@ -33,12 +35,12 @@
 
 static Eina_Bool
 _handle_op_a(Termpty *_ty EINA_UNUSED,
-             const char *txt,
-             const Eina_Unicode *_utxt EINA_UNUSED)
+             const Eina_Unicode *buf EINA_UNUSED,
+             size_t blen)
 {
-   switch (txt[1])
+   switch (buf[0])
      {
-      case 'a': // command aa*
+      case 'x': // command ax*
         break;
         // room here for more minor opcode chars like 'b', 'c' etc.
       default:
@@ -48,14 +50,22 @@ _handle_op_a(Termpty *_ty EINA_UNUSED,
 }
 
 Eina_Bool
-_termpty_ext_handle(Termpty *ty, const char *txt, const Eina_Unicode *utxt)
+termpty_ext_handle(Termpty *ty,
+                   const Eina_Unicode *buf,
+                   size_t blen)
 {
-   switch (txt[0]) // major opcode
+   switch (buf[0]) // major opcode
      {
       case 'a': // command a*
-        return _handle_op_a(ty, txt, utxt);
+        return _handle_op_a(ty, buf + 1, blen - 1);
         break;
         // room here for more major opcode chars like 'b', 'c' etc.
+#if defined(ENABLE_TESTS)
+      case 't':
+        tytest_handle_escape_codes(ty, buf + 1, blen - 1);
+        return EINA_FALSE;
+        break;
+#endif
       default:
         break;
      }
diff --git a/src/bin/termptyext.h b/src/bin/termptyext.h
index 8cf8cf9b..020219c8 100644
--- a/src/bin/termptyext.h
+++ b/src/bin/termptyext.h
@@ -1,6 +1,9 @@
 #ifndef _TERMPTY_EXT_H__
 #define _TERMPTY_EXT_H__ 1
 
-Eina_Bool _termpty_ext_handle(Termpty *ty, const char *txt, const Eina_Unicode *utxt);
+Eina_Bool
+termpty_ext_handle(Termpty *ty,
+                   const Eina_Unicode *buf,
+                   size_t blen);
 
 #endif
diff --git a/src/bin/tyfuzz.c b/src/bin/tyfuzz.c
index 14df9281..e30144c2 100644
--- a/src/bin/tyfuzz.c
+++ b/src/bin/tyfuzz.c
@@ -18,6 +18,9 @@
 #include "col.h"
 #include "tytest.h"
 #include "md5/md5.h"
+
+static void
+_tytest_checksum(Termpty *ty);
 #endif
 
 #define TY_H 25
@@ -192,159 +195,6 @@ termio_set_cursor_shape(Evas_Object *obj EINA_UNUSED,
 }
 #endif
 /* }}} */
-/* {{{ TYTEST */
-#ifdef TYTEST
-const char *_cursor_shape = "undefined";
-typedef struct _Termpty_Tests
-{
-   size_t backsize, backpos;
-   Backlog_Beacon backlog_beacon;
-   Term_State termstate;
-   Term_Cursor cursor_state;
-   Term_Cursor cursor_save[2];
-   int w, h;
-   unsigned int altbuf     : 1;
-   unsigned int mouse_mode : 3;
-   unsigned int mouse_ext  : 2;
-   unsigned int bracketed_paste : 1;
-} Termpty_Tests;
-
-Evas_Object *
-termio_textgrid_get(const Evas_Object *obj EINA_UNUSED)
-{
-   return NULL;
-}
-
-void
-test_textgrid_palette_get(const Evas_Object *obj EINA_UNUSED,
-                          Evas_Textgrid_Palette pal,
-                          int idx,
-                          int *r,
-                          int *g,
-                          int *b,
-                          int *a)
-{
-   if (pal == EVAS_TEXTGRID_PALETTE_EXTENDED)
-     {
-        colors_256_get(idx,
-                       (unsigned char *)r,
-                       (unsigned char *)g,
-                       (unsigned char *)b,
-                       (unsigned char *)a);
-     }
-   else
-     {
-        int set = idx / 12;
-        int col = idx % 12;
-        colors_standard_get(set, col,
-                            (unsigned char*)r,
-                            (unsigned char*)g,
-                            (unsigned char*)b,
-                            (unsigned char*)a);
-     }
-}
-
-void
-termio_set_cursor_shape(Evas_Object *obj EINA_UNUSED,
-                        Cursor_Shape shape EINA_UNUSED)
-{
-   switch (shape)
-     {
-      case CURSOR_SHAPE_UNDERLINE:
-         _cursor_shape = "underline";
-         break;
-      case CURSOR_SHAPE_BAR:
-         _cursor_shape = "bar";
-         break;
-      default:
-      case CURSOR_SHAPE_BLOCK:
-         _cursor_shape = "block";
-     }
-}
-
-static void
-_termpty_to_termpty_tests(Termpty *ty, Termpty_Tests *tt)
-{
-   memset(tt, '\0', sizeof(*tt));
-   tt->backsize = ty->backsize;
-   tt->backpos = ty->backpos;
-   tt->backlog_beacon = ty->backlog_beacon;
-   tt->termstate = ty->termstate;
-   tt->cursor_state = ty->cursor_state;
-   tt->cursor_save[0] = ty->cursor_save[0];
-   tt->cursor_save[1] = ty->cursor_save[1];
-   tt->w = ty->w;
-   tt->h = ty->h;
-   tt->altbuf = ty->altbuf;
-   tt->mouse_mode = ty->mouse_mode;
-   tt->mouse_ext = ty->mouse_ext;
-   tt->bracketed_paste = ty->bracketed_paste;
-}
-
-static void
-_tytest_checksum(Termpty *ty)
-{
-   MD5_CTX ctx;
-   Termpty_Tests tests;
-   char md5out[(2 * MD5_HASHBYTES) + 1];
-   unsigned char hash[MD5_HASHBYTES];
-   static const char hex[] = "0123456789abcdef";
-   int n;
-
-   _termpty_to_termpty_tests(ty, &tests);
-
-   MD5Init(&ctx);
-   /* Termpty */
-   MD5Update(&ctx,
-             (unsigned char const*)&tests,
-             sizeof(tests));
-   /* The screens */
-   MD5Update(&ctx,
-             (unsigned char const*)ty->screen,
-             sizeof(Termcell) * ty->w * ty->h);
-   MD5Update(&ctx,
-             (unsigned char const*)ty->screen2,
-             sizeof(Termcell) * ty->w * ty->h);
-   /* Icon/Title */
-   if (ty->prop.icon)
-     {
-        MD5Update(&ctx,
-                  (unsigned char const*)ty->prop.icon,
-                  strlen(ty->prop.icon));
-     }
-   else
-     {
-        MD5Update(&ctx, (unsigned char const*)"(NULL)", 6);
-     }
-   if (ty->prop.title)
-     {
-        MD5Update(&ctx,
-                  (unsigned char const*)ty->prop.title,
-                  strlen(ty->prop.title));
-     }
-   else
-     {
-        MD5Update(&ctx, (unsigned char const*)"(NULL)", 6);
-     }
-   /* Cursor shape */
-   MD5Update(&ctx, (unsigned char const*)_cursor_shape,
-             strlen(_cursor_shape));
-   /* Write buffer */
-   MD5Update(&ctx, (unsigned char const*)ty->write_buffer.buf,
-             ty->write_buffer.len);
-
-   MD5Final(hash, &ctx);
-
-   for (n = 0; n < MD5_HASHBYTES; n++)
-     {
-        md5out[2 * n] = hex[hash[n] >> 4];
-        md5out[2 * n + 1] = hex[hash[n] & 0x0f];
-     }
-   md5out[2 * MD5_HASHBYTES] = '\0';
-   printf("%s", md5out);
-}
-#endif
-/* }}} */
 
 
 
diff --git a/src/bin/tytest.c b/src/bin/tytest.c
index 95004b95..f33bb61b 100644
--- a/src/bin/tytest.c
+++ b/src/bin/tytest.c
@@ -1,2 +1,179 @@
 #define TYTEST 1
 #include "tyfuzz.c"
+
+const char *_cursor_shape = "undefined";
+
+typedef struct _Termpty_Tests
+{
+   size_t backsize, backpos;
+   Backlog_Beacon backlog_beacon;
+   Term_State termstate;
+   Term_Cursor cursor_state;
+   Term_Cursor cursor_save[2];
+   int w, h;
+   unsigned int altbuf     : 1;
+   unsigned int mouse_mode : 3;
+   unsigned int mouse_ext  : 2;
+   unsigned int bracketed_paste : 1;
+} Termpty_Tests;
+
+Evas_Object *
+termio_textgrid_get(const Evas_Object *obj EINA_UNUSED)
+{
+   return NULL;
+}
+
+void
+test_textgrid_palette_get(const Evas_Object *obj EINA_UNUSED,
+                          Evas_Textgrid_Palette pal,
+                          int idx,
+                          int *r,
+                          int *g,
+                          int *b,
+                          int *a)
+{
+   if (pal == EVAS_TEXTGRID_PALETTE_EXTENDED)
+     {
+        colors_256_get(idx,
+                       (unsigned char *)r,
+                       (unsigned char *)g,
+                       (unsigned char *)b,
+                       (unsigned char *)a);
+     }
+   else
+     {
+        int set = idx / 12;
+        int col = idx % 12;
+        colors_standard_get(set, col,
+                            (unsigned char*)r,
+                            (unsigned char*)g,
+                            (unsigned char*)b,
+                            (unsigned char*)a);
+     }
+}
+
+void
+termio_set_cursor_shape(Evas_Object *obj EINA_UNUSED,
+                        Cursor_Shape shape EINA_UNUSED)
+{
+   switch (shape)
+     {
+      case CURSOR_SHAPE_UNDERLINE:
+         _cursor_shape = "underline";
+         break;
+      case CURSOR_SHAPE_BAR:
+         _cursor_shape = "bar";
+         break;
+      default:
+      case CURSOR_SHAPE_BLOCK:
+         _cursor_shape = "block";
+     }
+}
+
+static void
+_termpty_to_termpty_tests(Termpty *ty, Termpty_Tests *tt)
+{
+   memset(tt, '\0', sizeof(*tt));
+   tt->backsize = ty->backsize;
+   tt->backpos = ty->backpos;
+   tt->backlog_beacon = ty->backlog_beacon;
+   tt->termstate = ty->termstate;
+   tt->cursor_state = ty->cursor_state;
+   tt->cursor_save[0] = ty->cursor_save[0];
+   tt->cursor_save[1] = ty->cursor_save[1];
+   tt->w = ty->w;
+   tt->h = ty->h;
+   tt->altbuf = ty->altbuf;
+   tt->mouse_mode = ty->mouse_mode;
+   tt->mouse_ext = ty->mouse_ext;
+   tt->bracketed_paste = ty->bracketed_paste;
+}
+
+static void
+_tytest_checksum(Termpty *ty)
+{
+   MD5_CTX ctx;
+   Termpty_Tests tests;
+   char md5out[(2 * MD5_HASHBYTES) + 1];
+   unsigned char hash[MD5_HASHBYTES];
+   static const char hex[] = "0123456789abcdef";
+   int n;
+
+   _termpty_to_termpty_tests(ty, &tests);
+
+   MD5Init(&ctx);
+   /* Termpty */
+   MD5Update(&ctx,
+             (unsigned char const*)&tests,
+             sizeof(tests));
+   /* The screens */
+   MD5Update(&ctx,
+             (unsigned char const*)ty->screen,
+             sizeof(Termcell) * ty->w * ty->h);
+   MD5Update(&ctx,
+             (unsigned char const*)ty->screen2,
+             sizeof(Termcell) * ty->w * ty->h);
+   /* Icon/Title */
+   if (ty->prop.icon)
+     {
+        MD5Update(&ctx,
+                  (unsigned char const*)ty->prop.icon,
+                  strlen(ty->prop.icon));
+     }
+   else
+     {
+        MD5Update(&ctx, (unsigned char const*)"(NULL)", 6);
+     }
+   if (ty->prop.title)
+     {
+        MD5Update(&ctx,
+                  (unsigned char const*)ty->prop.title,
+                  strlen(ty->prop.title));
+     }
+   else
+     {
+        MD5Update(&ctx, (unsigned char const*)"(NULL)", 6);
+     }
+   /* Cursor shape */
+   MD5Update(&ctx, (unsigned char const*)_cursor_shape,
+             strlen(_cursor_shape));
+   /* Write buffer */
+   MD5Update(&ctx, (unsigned char const*)ty->write_buffer.buf,
+             ty->write_buffer.len);
+
+   MD5Final(hash, &ctx);
+
+   for (n = 0; n < MD5_HASHBYTES; n++)
+     {
+        md5out[2 * n] = hex[hash[n] >> 4];
+        md5out[2 * n + 1] = hex[hash[n] & 0x0f];
+     }
+   md5out[2 * MD5_HASHBYTES] = '\0';
+   printf("%s", md5out);
+}
+
+static void
+_handle_mouse_down(Termpty *ty EINA_UNUSED,
+                   const Eina_Unicode *buf EINA_UNUSED,
+                   size_t blen EINA_UNUSED)
+{
+}
+
+/* Testing escape codes that start with '\033}t' and end with '\0'
+ * Then,
+ * - 'd': mouse down:
+ */
+void
+tytest_handle_escape_codes(Termpty *ty,
+                           const Eina_Unicode *buf,
+                           size_t blen)
+{
+   switch (buf[0])
+     {
+      case 'd':
+        return _handle_mouse_down(ty, buf + 1, blen - 1);
+        break;
+      default:
+        break;
+     }
+}
diff --git a/src/bin/tytest.h b/src/bin/tytest.h
index e702cec5..2164ff0e 100644
--- a/src/bin/tytest.h
+++ b/src/bin/tytest.h
@@ -11,5 +11,9 @@ test_textgrid_palette_get(const Evas_Object *obj,
                           int *g,
                           int *b,
                           int *a);
+void
+tytest_handle_escape_codes(Termpty *ty,
+                           const Eina_Unicode *buf,
+                           size_t blen);
 #endif
 #endif