nemanjamalesija/ts-expand-hover.nvim

github

lsp

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CREATED

2026-02-23

UPDATED

2026-10-13

---

ts-expand-hover.nvim

The expandable type hover from VS Code, for Neovim: a TypeScript hover where you expand type aliases in place.

The normal hover shows Props and stops there. With this plugin you open the hover, press + and Props turns into the object it stands for. Press it again to go one level deeper, - to go back. The float stays where it is and just updates its text.

It uses the verbosityLevel hover option TypeScript added in 5.9. It works with vtsls and with the TypeScript 7 server (tsc --lsp, also called tsgo).

Requirements

• Neovim 0.10 or newer
• One of these servers attached to your TypeScript buffers:
  • vtsls 0.2.9 or newer, running TypeScript 5.9 or newer. vtsls 0.3.0 ships with 5.9, so that is the easy route.
  • The TypeScript 7 server, which nvim-lspconfig calls tsc (tsgo in older versions). It needs one extra capability, see TypeScript 7 setup.

Installation

With lazy.nvim:

{
  "nemanjamalesija/ts-expand-hover.nvim",
  ft = { "typescript", "typescriptreact" },
  opts = {
    keymaps = { hover = "<leader>th" },
  },
}

With any other plugin manager, call require("ts_expand_hover").setup() after the plugin loads.

TypeScript 7 setup

The TypeScript 7 server only tells the plugin whether a type can expand further if the client declares the experimental.hoverVerbosityLevel capability. Without it the float opens, but + does nothing. Add it to your tsc config (Neovim 0.11+ shown):

-- On older nvim-lspconfig the server is called "tsgo".
-- Use that name here and in vim.lsp.enable().
vim.lsp.config("tsc", {
  capabilities = { experimental = { hoverVerbosityLevel = true } },
  -- Optional. The server cuts long types at 500 characters and shows
  -- "... N more ..." in their place. Raise the cap to see big types whole.
  settings = { ["js/ts"] = { maximumHoverLength = 5000 } },
})
vim.lsp.enable("tsc")

TypeScript marks this capability as experimental, so support for the TypeScript 7 server is experimental here too.

Usage

The bottom row of the float shows how deep you are and shows [max] when there is nothing left to expand. The float closes when you move the cursor in the source buffer.

Below the type you get the documentation and JSDoc tags (@param, @returns, @example). The type itself is highlighted with treesitter.

If no supported server is attached, or the server returns an error, K falls back to the built-in vim.lsp.buf.hover(). If both vtsls and the TypeScript 7 server are attached, the plugin uses vtsls.

Configuration

These are the defaults. setup() with no arguments gives you exactly this:

require("ts_expand_hover").setup({
  keymaps = {
    hover    = "K",
    expand   = "+",  -- = works too
    collapse = "-",
    close    = { "q", "<Esc>" },
  },
  float = {
    border     = "rounded",  -- "rounded", "single", "double", "none"
    max_width  = 80,
    max_height = 30,
  },
})

Set a keymap to false and the plugin won't register it. This is handy if something else already uses K and you only want the plugin's hover in TypeScript files:

require("ts_expand_hover").setup({
  keymaps = { hover = false },
})

vim.api.nvim_create_autocmd("FileType", {
  pattern = { "typescript", "typescriptreact" },
  callback = function(ev)
    vim.keymap.set("n", "K", require("ts_expand_hover").hover, {
      buffer = ev.buf,
      desc = "TypeScript expandable hover",
    })
  end,
})

Troubleshooting

Start with :checkhealth ts_expand_hover, with a TypeScript file open so the server has attached. It shows your Neovim version, which server is attached and its TypeScript version, and for the TypeScript 7 server whether the capability is declared.

You get the standard LSP hover instead of this one: no supported server is attached to the buffer.

+ does nothing: either the bottom row says [max], vtsls is running a TypeScript older than 5.9, or the TypeScript 7 server is missing the capability from TypeScript 7 setup.

A type ends in ... N more ...: the TypeScript 7 server cut it at maximumHoverLength. Raise that setting, also shown in TypeScript 7 setup.

How it works

Both servers accept a verbosityLevel with the hover request and answer whether the type can expand further. K asks for level 0, + and - ask again one level up or down and the plugin swaps the text in the float.

With vtsls the request goes through workspace/executeCommand as a typescript.tsserverRequest for tsserver's quickinfo command. With the TypeScript 7 server it is a plain textDocument/hover request with verbosityLevel added.

Tests

make test

Needs Neovim and plenary.nvim. The tests run headless and don't need a language server.

License

MIT