Feature parse def

[utubo]

I implemented a def parser to ensure that return statements inside a def do not trigger E133. Additionally, since CI failed on the latest Ubuntu, test.yaml has been updated.

Changes

• vimlparser.vim

  • Prevent E133 :return not inside a function
  • Check these errors in def
    • E126: Missing :enddef
    • E193: :enddef not inside a def
    • E1003: Missing return value
    • E1263: Cannot use name with # in Vim9 script, use export instead
    • E1267: Function name must start with a capital: %s
    • E1268: Cannot use s: in Vim9 script (def name)
    • E1069: White space required after ':' (type of arguments or return type of def)
    • E1069: White space required after ',' (after arguments)
    • E1077: Missing argument type for %s
    • E1096: Returning a value in a function without a return type
    • E1126: Cannot use :let in Vim9 script
    • E1263: Cannot use name with # in Vim9 script, use export instead
    • E1267: Function name must start with a capital: %s
  • fix some typos.

• jscompiler.vim

  • Implements slice().
  • Sets undefined to a variable instead of deleting it

• pycompiler.vim

  • Implements slice().

• test.yaml

  • Fix version of ubuntu for covimerage.
    see covimerage.CoveragePlugin not supported with PyTracer after upgrade to ubuntu 24.04 Vimjas/covimerage#104

• Not addressed in this PR (due to complexity)

  • Strict type checking
  • lambda
  • E477: No ! allowed e.g.) def! Foo()