Commit: patch 9.0.1948: Vim9: object variable "this." should only be used in constructor

[Christian Brabandt]

patch 9.0.1948: Vim9: object variable "this." should only be used in constructor

Commit: https://github.com/vim/vim/commit/db38552dcdc7460459df8bf5cf02666256045308
Author: h-east <h.eas...@gmail.com>
Date: Thu Sep 28 22:18:19 2023 +0200

patch 9.0.1948: Vim9: object variable "this." should only be used in constructor

Problem: Vim9: object variable "this." should only be used in
constructor
Solution: Disallow to this in normal object methods (other than
constructors)

closes: #13152
closes: #13212

Signed-off-by: Christian Brabandt <c...@256bit.org>
Co-authored-by: h-east <h.eas...@gmail.com>

diff --git a/runtime/doc/tags b/runtime/doc/tags
index 918e76772..13baf8fd1 100644
--- a/runtime/doc/tags
+++ b/runtime/doc/tags
@@ -4483,6 +4483,7 @@ E1387 vim9class.txt /*E1387*
E1388 vim9class.txt /*E1388*
E1389 vim9class.txt /*E1389*
E139 message.txt /*E139*
+E1390 vim9class.txt /*E1390*
E140 message.txt /*E140*
E1400 builtin.txt /*E1400*
E1401 builtin.txt /*E1401*
diff --git a/runtime/doc/vim9class.txt b/runtime/doc/vim9class.txt
index b230cb800..7b9f8b4a6 100644
--- a/runtime/doc/vim9class.txt
+++ b/runtime/doc/vim9class.txt
@@ -216,7 +216,8 @@ see this pattern: >
this.col = col
enddef
endclass
-
+<
+ *E1390*
Not only is this text you need to write, it also has the type of each
variables twice. Since this is so common a shorter way to write new() is
provided: >
diff --git a/src/errors.h b/src/errors.h
index 7260c30cb..baf36d5e4 100644
--- a/src/errors.h
+++ b/src/errors.h
@@ -3529,6 +3529,8 @@ EXTERN char e_public_keyword_not_supported_for_method[]
INIT(= N_("E1388: Public keyword not supported for a method"));
EXTERN char e_missing_name_after_implements[]
INIT(= N_("E1389: Missing name after implements"));
+EXTERN char e_cannot_use_an_object_variable_except_with_the_new_method_str[]
+ INIT(= N_("E1390: Cannot use an object variable \"this.%s\" except with the \"new\" method"));
#endif
EXTERN char e_cannot_mix_positional_and_non_positional_str[]
INIT(= N_("E1400: Cannot mix positional and non-positional arguments: %s"));
@@ -3544,4 +3546,4 @@ EXTERN char e_invalid_format_specifier_str[]
INIT(= N_("E1405: Invalid format specifier: %s"));
EXTERN char e_aptypes_is_null_nr_str[]
INIT(= "E1408: Internal error: ap_types or ap_types[idx] is NULL: %d: %s");
-// E1390 - E1399 unused
+// E1391 - E1399 unused
diff --git a/src/testdir/test_vim9_class.vim b/src/testdir/test_vim9_class.vim
index 2fd66c937..c272aab39 100644
--- a/src/testdir/test_vim9_class.vim
+++ b/src/testdir/test_vim9_class.vim
@@ -955,6 +955,17 @@ def Test_class_new_with_object_member()
END
v9.CheckSourceFailure(lines, 'E1013:')

+ lines =<< trim END
+ vim9script
+
+ class C
+ this.str: string
+ def MethodA(this.str)
+ enddef
+ endclass
+ END
+ v9.CheckSourceFailure(lines, 'E1390: Cannot use an object variable "this.str" except with the "new" method')
+
lines =<< trim END
vim9script

diff --git a/src/userfunc.c b/src/userfunc.c
index e0c1d5f91..0f487fc12 100644
--- a/src/userfunc.c
+++ b/src/userfunc.c
@@ -320,6 +320,16 @@ get_function_args(
++p;
char_u *argend = p;

+ // object variable this. can be used only in a constructor
+ if (STRNCMP(eap->arg, "new", 3) != 0)
+ {
+ c = *argend;
+ *argend = NUL;
+ semsg(_(e_cannot_use_an_object_variable_except_with_the_new_method_str), arg);
+ *argend = c;
+ break;
+ }
+
if (*skipwhite(p) == '=')
{
char_u *defval = skipwhite(skipwhite(p) + 1);
diff --git a/src/version.c b/src/version.c
index fb1b30713..49b406781 100644
--- a/src/version.c
+++ b/src/version.c
@@ -699,6 +699,8 @@ static char *(features[]) =

static int included_patches[] =
{ /* Add new patch number below this line */
+/**/
+ 1948,
/**/
1947,
/**/

[Christ van Willegen]

Hi, 

Op do 28 sep. 2023 22:30 schreef Christian Brabandt <cbl...@256bit.org>:

+           // object variable this. can be used only in a constructor
+           if (STRNCMP(eap->arg, "new", 3) != 0)
+           {
+               c = *argend;
+               *argend = NUL;
+               semsg(_(e_cannot_use_an_object_variable_except_with_the_new_method_str), arg);
+               *argend = c;
+               break;
+           }
+

Will this check fail if the class method using "this." is called newCalculation()? Or are any methods starting with "new" disallowed?

Christ van Willegen