CHANGES:

## Features

- Add a new code action `Add missing rec keyword`, which is available when
  adding a `rec` keyword can fix `Unbound value ...` error, e.g.,

  ```ocaml
  let fact n = if n = 0 then 1 else n * fact (n - 1)
                                     (* ^^^^ Unbound value fact *)
  ```

  Adding `rec` to the definition of `fact` will fix the problem. The new code
  action offers adding `rec`.

- Jump to the first hole on calling `Destruct` code action (only with client
  VSCode OCaml Platform) (ocaml/ocaml-lsp#468)

  Example: when a user invokes `Destruct` code action on `Some 1`, this code is
  replaced by `match Some 1 with None -> _ | Some _ -> _`, where the 1st and
  3rd underscores are "typed holes", a concept created by Merlin to be able to
  put "holes" in OCaml code.

  With this change, now for VSCode OCaml Platform users, on such invocation of
  `Destruct`, the cursor will jump to the first typed hole and select it, so
  that user can start editing right away.

- Use ocamlformat to properly format type snippets. This feature requires the
  `ocamlformat-rpc` opam package to be installed. (ocaml/ocaml-lsp#386)

- Add completion support for polymorphic variants, when it is possible to pin
  down the precise type. Examples (`<|>` stands for the cursor) when completion
  will work (ocaml/ocaml-lsp#473)

  Function application:

  ```
  let foo (a: [`Alpha | `Beta]) = ()

  foo `A<|>
  ```

  Type explicitly shown:

  ```
  let a : [`Alpha | `Beta] = `B<|>
  ```

  Note: this is actually a bug fix, since we were ignoring the backtick when
  constructing the prefix for completion.

- Parse merlin errors (best effort) into a more structured form. This allows
  reporting all locations as "related information" (ocaml/ocaml-lsp#475)

- Add support for Merlin `Construct` command as completion suggestions, i.e.,
  show complex expressions that could complete the typed hole. (ocaml/ocaml-lsp#472)

- Add a code action `Construct an expression` that is shown when the cursor is
  at the end of the typed hole, i.e., `_|`, where `|` is the cursor. The code
  action simply triggers the client (currently only VS Code is supported) to
  show completion suggestions. (ocaml/ocaml-lsp#472)

- Change the formatting-on-save error notification to a warning notification
  (ocaml/ocaml-lsp#472)

- Code action to qualify ("put module name in identifiers") and unqualify
  ("remove module name from identifiers") module names in identifiers (ocaml/ocaml-lsp#399)

  Starting from:

  ```ocaml
  open Unix

  let times = Unix.times ()
  let f x = x.Unix.tms_stime, x.Unix.tms_utime
  ```

  Calling "remove module name from identifiers" with the cursor on the open
  statement will produce:

  ```ocaml
  open Unix

  let times = times ()
  let f x = x.tms_stime, x.tms_utime
  ```

  Calling "put module name in identifiers" will restore:

  ```ocaml
  open Unix

  let times = Unix.times ()
  let f x = x.Unix.tms_stime, x.Unix.tms_utime
  ```

## Fixes

- Do not show "random" documentation on hover

  - fixed by [merlin#1364](ocaml/merlin#1364)
  - fixes duplicate:
    - [ocaml-lsp#344](ocaml/ocaml-lsp#344)
    - [vscode-ocaml-platform#111](ocamllabs/vscode-ocaml-platform#111)

- Correctly rename a variable used as a named/optional argument (ocaml/ocaml-lsp#478)

- When reporting an error at the beginning of the file, use the first line not
  the second (ocaml/ocaml-lsp#489)