patch 8.2.2453: Vim9: a variable name with "->" in the next line doesn't work

Problem:    Vim9: a variable name with "->" in the next line doesn't work.
Solution:   Recognize a variable name by itself. (closes #7770)

Author: brammool

src/ex_docmd.c

@@ -3424,6 +3424,16 @@ find_ex_command(
 		return eap->cmd;
 	    }
 	}
+
+	// If it is an ID it might be a variable with an operator on the next
+	// line, if the variable exists it can't be an Ex command.
+	if (p > eap->cmd && ends_excmd(*skipwhite(p))
+		&& (lookup(eap->cmd, p - eap->cmd, NULL, cctx) == OK
+		    || (ASCII_ISALPHA(eap->cmd[0]) && eap->cmd[1] == ':')))
+	{
+	    eap->cmdidx = CMD_eval;
+	    return eap->cmd;
+	}
     }
 #endif
 

src/testdir/test_vim9_cmd.vim

@@ -328,6 +328,29 @@ def Test_method_call_linebreak()
       assert_equal([1, 2, 3], res)
   END
   CheckScriptSuccess(lines)
+
+  lines =<< trim END
+      new
+      var name = [1, 2]
+      name
+          ->copy()
+          ->setline(1)
+      assert_equal(['1', '2'], getline(1, 2))
+      bwipe!
+  END
+  CheckDefAndScriptSuccess(lines)
+
+  lines =<< trim END
+      new
+      g:shortlist
+          ->copy()
+          ->setline(1)
+      assert_equal(['1', '2'], getline(1, 2))
+      bwipe!
+  END
+  g:shortlist = [1, 2]
+  CheckDefAndScriptSuccess(lines)
+  unlet g:shortlist
 enddef
 
 def Test_method_call_whitespace()

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2453,
 /**/
     2452,
 /**/