patch 9.0.2041: trim(): hard to use default mask

Problem:  trim(): hard to use default mask (partly revert v9.0.2040)
Solution: use default mask when it is empty

The default 'mask' value is pretty complex, as it includes many
characters.  Yet, if one needs to specify the trimming direction, the
third argument, 'trim()' currently requires the 'mask' value to be
provided explicitly.

Currently, an empty 'mask' will make 'trim()' call return 'text' value
that is passed in unmodified.  It is unlikely that someone is using it,
so the chances of scripts being broken by this change are low.

Also, this reverts commit 9.0.2040 (which uses v:none for the default
and requires to use an empty string instead).

closes: #13358

Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: Illia Bobyr <illia.bobyr@gmail.com>

runtime/doc/builtin.txt

@@ -10119,10 +10119,9 @@ trim({text} [, {mask} [, {dir}]])				*trim()*
 		Return {text} as a String where any character in {mask} is
 		removed from the beginning and/or end of {text}.
 
-		If {mask} is not given, or is |v:none| (see
-		|none-function_argument|), {mask} is all characters up to
-		0x20, which includes Tab, space, NL and CR, plus the
-		non-breaking space character 0xa0.
+		If {mask} is not given, or is an empty string, {mask} is all
+		characters up to 0x20, which includes Tab, space, NL and CR,
+		plus the non-breaking space character 0xa0.
 
 		The optional {dir} argument specifies where to remove the
 		characters:

src/errors.h

@@ -3539,8 +3539,6 @@ EXTERN char e_cannot_lock_object_variable_str[]
 EXTERN char e_cannot_lock_class_variable_str[]
 	INIT(= N_("E1392: Cannot (un)lock class variable \"%s\" in class \"%s\""));
 #endif
-EXTERN char e_string_or_none_required_for_argument_nr[]
-	INIT(= N_("E1393: String or v:none required for argument %d"));
 // E1393 - E1499 unused (reserved for Vim9 class support)
 EXTERN char e_cannot_mix_positional_and_non_positional_str[]
 	INIT(= N_("E1500: Cannot mix positional and non-positional arguments: %s"));

src/proto/typval.pro

@@ -14,7 +14,6 @@ int check_for_unknown_arg(typval_T *args, int idx);
 int check_for_string_arg(typval_T *args, int idx);
 int check_for_nonempty_string_arg(typval_T *args, int idx);
 int check_for_opt_string_arg(typval_T *args, int idx);
-int check_for_opt_string_or_none_arg(typval_T *args, int idx, int *is_none);
 int check_for_number_arg(typval_T *args, int idx);
 int check_for_opt_number_arg(typval_T *args, int idx);
 int check_for_float_or_nr_arg(typval_T *args, int idx);

src/strings.c

@@ -1962,7 +1962,7 @@ f_trim(typval_T *argvars, typval_T *rettv)
 
     if (in_vim9script()
 	    && (check_for_string_arg(argvars, 0) == FAIL
-		|| check_for_opt_string_or_none_arg(argvars, 1, NULL) == FAIL
+		|| check_for_opt_string_arg(argvars, 1) == FAIL
 		|| (argvars[1].v_type != VAR_UNKNOWN
 		    && check_for_opt_number_arg(argvars, 2) == FAIL)))
 	return;
@@ -1971,13 +1971,16 @@ f_trim(typval_T *argvars, typval_T *rettv)
     if (head == NULL)
 	return;
 
-    if (check_for_opt_string_or_none_arg(argvars, 1, NULL) == FAIL)
+    if (check_for_opt_string_arg(argvars, 1) == FAIL)
 	return;
 
     if (argvars[1].v_type == VAR_STRING)
+    {
 	mask = tv_get_string_buf_chk(&argvars[1], buf2);
+	if (*mask == NUL)
+	    mask = NULL;
 
-    if (argvars[1].v_type != VAR_UNKNOWN && argvars[2].v_type != VAR_UNKNOWN)
+	if (argvars[2].v_type != VAR_UNKNOWN)
 	{
 	    int	error = 0;
 
@@ -1991,6 +1994,7 @@ f_trim(typval_T *argvars, typval_T *rettv)
 		return;
 	    }
 	}
+    }
 
     if (dir == 0 || dir == 1)
     {

src/testdir/test_functions.vim

@@ -2231,14 +2231,14 @@ func Test_trim()
   call assert_fails('eval trim("  vim  ", " ", [])', 'E745:')
   call assert_fails('eval trim("  vim  ", " ", -1)', 'E475:')
   call assert_fails('eval trim("  vim  ", " ", 3)', 'E475:')
-  call assert_fails('eval trim("  vim  ", 0)', 'E1393:')
+  call assert_fails('eval trim("  vim  ", 0)', 'E1174:')
 
   let chars = join(map(range(1, 0x20) + [0xa0], {n -> n->nr2char()}), '')
   call assert_equal("x", trim(chars . "x" . chars))
 
-  call assert_equal("x", trim(chars . "x" . chars, v:none, 0))
-  call assert_equal("x" . chars, trim(chars . "x" . chars, v:none, 1))
-  call assert_equal(chars . "x", trim(chars . "x" . chars, v:none, 2))
+  call assert_equal("x", trim(chars . "x" . chars, '', 0))
+  call assert_equal("x" . chars, trim(chars . "x" . chars, '', 1))
+  call assert_equal(chars . "x", trim(chars . "x" . chars, '', 2))
 
   call assert_fails('let c=trim([])', 'E730:')
 endfunc

src/testdir/test_vim9_builtin.vim

@@ -4786,7 +4786,7 @@ enddef
 
 def Test_trim()
   v9.CheckDefAndScriptFailure(['trim(["a"])'], ['E1013: Argument 1: type mismatch, expected string but got list<string>', 'E1174: String required for argument 1'])
-  v9.CheckDefAndScriptFailure(['trim("a", ["b"])'], ['E1013: Argument 2: type mismatch, expected string but got list<string>', 'E1393: String or v:none required for argument 2'])
+  v9.CheckDefAndScriptFailure(['trim("a", ["b"])'], ['E1013: Argument 2: type mismatch, expected string but got list<string>', 'E1174: String required for argument 2'])
   v9.CheckDefAndScriptFailure(['trim("a", "b", "c")'], ['E1013: Argument 3: type mismatch, expected number but got string', 'E1210: Number required for argument 3'])
   trim('')->assert_equal('')
   trim('', '')->assert_equal('')

src/typval.c

@@ -450,37 +450,6 @@ check_for_opt_string_arg(typval_T *args, int idx)
 	    || check_for_string_arg(args, idx) != FAIL) ? OK : FAIL;
 }
 
-/*
- * Check for an optional string argument at 'idx', that can also be 'v:none' to
- * use the default value.
- *
- * If 'is_none' is non-NULL it is set to 0 and updated to 1 when "args[idx]" is
- * 'v:none'.
- */
-    int
-check_for_opt_string_or_none_arg(typval_T *args, int idx, int *is_none)
-{
-    if (is_none != NULL)
-	*is_none = 0;
-
-    if (args[idx].v_type == VAR_UNKNOWN)
-	return OK;
-
-    if (args[idx].v_type == VAR_SPECIAL
-	    && args[idx].vval.v_number == VVAL_NONE)
-    {
-	if (is_none != NULL)
-	    *is_none = 1;
-	return OK;
-    }
-
-    if (args[idx].v_type == VAR_STRING)
-	return OK;
-
-    semsg(_(e_string_or_none_required_for_argument_nr), idx + 1);
-    return FAIL;
-}
-
 /*
  * Give an error and return FAIL unless "args[idx]" is a number.
  */

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2041,
 /**/
     2040,
 /**/