Problem:
`vim.diagnostic.is_disabled` and `vim.diagnostic.disable` are unnecessary
and inconsistent with the "toggle" pattern (established starting with
`vim.lsp.inlay_hint`, see https://github.com/neovim/neovim/pull/25512#pullrequestreview-1676750276
As a reminder, the rationale is:
- we always need `enable()`
- we always end up needing `is_enabled()`
- "toggle" can be achieved via `enable(not is_enabled())`
- therefore,
- `toggle()` and `disable()` are redundant
- `is_disabled()` is a needless inconsistency
Solution:
- Introduce `vim.diagnostic.is_enabled`, and `vim.diagnostic.enable(…, enable:boolean)`
- Note: Future improvement would be to add an `enable()` overload `enable(enable:boolean, opts: table)`.
- Deprecate `vim.diagnostic.is_disabled`, `vim.diagnostic.disable`
26765e8461