patch 8.2.3023: Vim9: arguments for execute() not checked at compile time

Problem:    Vim9: arguments for execute() not checked at compile time.
Solution:   Add a function to check the argument types.

src/evalfunc.c

@@ -301,6 +301,27 @@ arg_list_or_blob(type_T *type, argcontext_T *context)
     return FAIL;
 }
 
+/*
+ * Check "type" is a string or a list of strings.
+ */
+    static int
+arg_string_or_list(type_T *type, argcontext_T *context)
+{
+    if (type->tt_type == VAR_ANY || type->tt_type == VAR_STRING)
+	return OK;
+    if (type->tt_type != VAR_LIST)
+    {
+	arg_type_mismatch(&t_string, type, context->arg_idx + 1);
+	return FAIL;
+    }
+    if (type->tt_member->tt_type == VAR_ANY
+		    || type->tt_member->tt_type == VAR_STRING)
+	return OK;
+
+    arg_type_mismatch(&t_list_string, type, context->arg_idx + 1);
+    return FAIL;
+}
+
 /*
  * Check "type" is a list or a dict.
  */
@@ -385,6 +406,7 @@ argcheck_T arg1_string[] = {arg_string};
 argcheck_T arg3_string_nr_bool[] = {arg_string, arg_number, arg_bool};
 argcheck_T arg1_float_or_nr[] = {arg_float_or_nr};
 argcheck_T arg2_listblob_item[] = {arg_list_or_blob, arg_item_of_prev};
+argcheck_T arg2_execute[] = {arg_string_or_list, arg_string};
 argcheck_T arg23_extend[] = {arg_list_or_dict, arg_same_as_prev, arg_extend3};
 argcheck_T arg23_extendnew[] = {arg_list_or_dict, arg_same_struct_as_prev, arg_extend3};
 argcheck_T arg3_insert[] = {arg_list_or_blob, arg_item_of_prev, arg_number};
@@ -870,7 +892,7 @@ static funcentry_T global_functions[] =
 			ret_number_bool,    f_eventhandler},
     {"executable",	1, 1, FEARG_1,	    NULL,
 			ret_number,	    f_executable},
-    {"execute",		1, 2, FEARG_1,	    NULL,
+    {"execute",		1, 2, FEARG_1,	    arg2_execute,
 			ret_string,	    f_execute},
     {"exepath",		1, 1, FEARG_1,	    NULL,
 			ret_string,	    f_exepath},

src/testdir/test_vim9_builtin.vim

@@ -324,6 +324,18 @@ def Test_executable()
   CheckDefExecFailure(['echo executable(true)'], 'E1174:')
 enddef
 
+def Test_execute()
+  var res = execute("echo 'hello'")
+  assert_equal("\nhello", res)
+  res = execute(["echo 'here'", "echo 'there'"])
+  assert_equal("\nhere\nthere", res)
+
+  CheckDefFailure(['echo execute(123)'], 'E1013: Argument 1: type mismatch, expected string but got number')
+  CheckDefFailure(['echo execute([123])'], 'E1013: Argument 1: type mismatch, expected list<string> but got list<number>')
+  CheckDefExecFailure(['echo execute(["xx", 123])'], 'E492')
+  CheckDefFailure(['echo execute("xx", 123)'], 'E1013: Argument 2: type mismatch, expected string but got number')
+enddef
+
 def Test_exepath()
   CheckDefExecFailure(['echo exepath(true)'], 'E1174:')
   CheckDefExecFailure(['echo exepath(v:null)'], 'E1174:')

src/version.c

@@ -755,6 +755,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3023,
 /**/
     3022,
 /**/