patch 9.0.1898: Vim9: restrict access to static vars Commit: https://github.com/vim/vim/commit/c30a90d9b2c029f794cea502f6b824f71e4876dd Author: Yegappan Lakshmanan <yegappan@yahoo.com> Date: Fri Sep 15 20:14:55 2023 +0200 patch 9.0.1898: Vim9: restrict access to static vars Problem: Vim9: restrict access to static vars and methods Solution: Class members are accesible only from the class where they are defined. Based on the #13004 discussion, the following changes are made: 1) Static variables and methods are accessible only using the class name and inside the class where they are defined. 2) Static variables and methods can be used without the class name in the class where they are defined. 3) Static variables of a super class are not copied to the sub class. 4) A sub class can declare a class variable with the same name as the super class. 5) When a method or member is found during compilation, use more specific error messages. This aligns the Vim9 class variable/method implementation with the Dart implementation. Also while at it, ignore duplicate class and object methods. The access level of an object method can however be changed in a subclass. For the tests, use the new CheckSourceFailure() function instead of the CheckScriptFailure() function in the tests. closes: #13086 Signed-off-by: Christian Brabandt <cb@256bit.org> Co-authored-by: Yegappan Lakshmanan <yegappan@yahoo.com>