patch 8.2.1943: Vim9: wrong error message when colon is missing

Problem:    Vim9: wrong error message when colon is missing.
Solution:   Check for a missing colon. (issue #7239)

Author: brammool

src/ex_docmd.c

@@ -1807,12 +1807,19 @@ do_one_cmd(
 	if (ea.cmd == cmd + 1 && *cmd == '$')
 	    // should be "$VAR = val"
 	    --ea.cmd;
-	else if (ea.cmd > cmd)
+	p = find_ex_command(&ea, NULL, lookup_scriptvar, NULL);
+	if (ea.cmdidx == CMD_SIZE)
 	{
-	    emsg(_(e_colon_required_before_a_range));
-	    goto doend;
+	    char_u *ar = skip_range(ea.cmd, TRUE, NULL);
+
+	    // If a ':' before the range is missing, give a clearer error
+	    // message.
+	    if (ar > ea.cmd)
+	    {
+		emsg(_(e_colon_required_before_a_range));
+		goto doend;
+	    }
 	}
-	p = find_ex_command(&ea, NULL, lookup_scriptvar, NULL);
     }
     else
 #endif

src/testdir/test_vim9_cmd.vim

@@ -460,6 +460,15 @@ def Test_command_modifier_other()
   # verbose
 enddef
 
+def Test_range_after_command_modifier()
+  CheckScriptFailure(['vim9script', 'silent keepjump 1d _'], 'E1050:', 2)
+  new
+  setline(1, 'xxx')
+  CheckScriptSuccess(['vim9script', 'silent keepjump :1d _'])
+  assert_equal('', getline(1))
+  bwipe!
+enddef
+
 def Test_eval_command()
   var from = 3
   var to = 5

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1943,
 /**/
     1942,
 /**/