termptyesc: extract ECH handler to its own function + test

Test is not fully working at the moment.
There seems to be an issue with appending text outside margins

src/bin/termptyesc.c

@@ -2790,6 +2790,19 @@ _handle_esc_csi_tbc(Termpty *ty, Eina_Unicode **ptr)
      }
 }
 
+static void
+_handle_esc_csi_ech(Termpty *ty, Eina_Unicode **ptr)
+{
+   Eina_Unicode *b = *ptr;
+   int arg = _csi_arg_get(ty, &b);
+
+   if (arg == -CSI_ARG_ERROR)
+     return;
+   DBG("ECH - Erase Character: %d", arg);
+   TERMPTY_RESTRICT_FIELD(arg, 1, ty->w);
+   termpty_clear_line(ty, TERMPTY_CLR_END, arg);
+}
+
 static int
 _handle_esc_csi(Termpty *ty, const Eina_Unicode *c, const Eina_Unicode *ce)
 {
@@ -2891,13 +2904,8 @@ _handle_esc_csi(Termpty *ty, const Eina_Unicode *c, const Eina_Unicode *ce)
         else
           _handle_esc_csi_ctc(ty, &b);
         break;
-      case 'X': // erase N chars
-        arg = _csi_arg_get(ty, &b);
-        if (arg == -CSI_ARG_ERROR)
-          goto error;
-        TERMPTY_RESTRICT_FIELD(arg, 1, ty->w);
-        DBG("ECH: erase %d chars", arg);
-        termpty_clear_line(ty, TERMPTY_CLR_END, arg);
+      case 'X':
+        _handle_esc_csi_ech(ty, &b);
         break;
       case 'Z':
           {

tests/ech.sh

@@ -0,0 +1,85 @@
+#!/bin/sh
+
+# fill space
+PL=1
+for _ in $(seq 0 23); do
+    PL=$((PL+1))
+    if [ $PL -gt 9 ] ; then
+        PL=1
+    fi
+    printf '%s' "$PL"
+    for _ in $(seq 2 $PL); do
+        printf '#'
+    done
+    PR=$((9 - PL))
+    for _ in $(seq 0 6); do
+        printf '\033[0;1m\-'
+        printf '\033[0;46;1;4m/'
+        printf '\033[0;46;1;4m|'
+        printf '\033[0;1;4;7m\\'
+        printf '\033[0m~'
+        printf '\033[0;1m_'
+        printf '\033[0;31;7m>'
+        printf '\033[0;31;4;7m^'
+        printf '\033[0;1;7m<'
+    done
+    printf '\033[0m'
+    for _ in $(seq 1 $PR); do
+        printf '#'
+    done
+    printf '%s' "$PR"
+done
+
+# set color
+printf '\033[43;32;3m'
+
+# move
+printf '\033[1;10H'
+# ECH 0
+printf '1>\033[0X'
+# move
+printf '\033[3;10H'
+# ECH default
+printf '2>\033[X'
+# move
+printf '\033[5;10H'
+# ECH 3
+printf '3>\033[3X'
+
+
+# set top/bottom margins:
+printf '\033[8;14r'
+# allow left/right margins
+printf '\033[?69h'
+# set left/right margins:
+printf '\033[5;75s'
+
+# move
+printf '\033[7;10H'
+# outside margins (top)
+printf '4>\033[X'
+# move
+printf '\033[8;1H'
+# outside margins(left)
+printf '5>\033[X'
+# move
+printf '\033[15;10H'
+# outside margins(bottom)
+printf '6>\033[X'
+# move
+printf '\033[8;76H'
+# outside margins(right)
+printf '7>\033[X'
+
+# move
+printf '\033[9;10H'
+# ECH full line
+printf '8>\033[88888X'
+
+# restrict cursor
+printf '\033[?6h'
+
+# move
+printf '\033[4;4H'
+# ECH still goes outside margins
+printf '9>\033[888X'

tests/tests.results

@@ -65,3 +65,4 @@ sd.sh 4bfda7ec3e6192acab077de2bc270525
 decst8c.sh 0ea805e8f4c2626ce66c566a10548d0f
 ctc.sh d35eeacdb2e99f5ac8cc3c4e8d72f8b0
 tbc.sh d0216e4056e5ab1cb4d411b6d6074785
+ech.sh 6257d40c467d63cc7883c380357d87f7