Legacy TypeScript Extra

lang.typescript-legacy is the optional ts_ls TypeScript and JavaScript stack. It keeps the picker, keymaps, and editing model unchanged while adding language tooling for JS, TS, JSX, TSX, JSON, and JSONC files.

Use this when a project needs ts_ls or TypeScript server plugins. The standard lang.typescript extra uses native TypeScript 7. Disable lang.typescript and lang.typescript-tsgo before enabling the legacy extra, and restart after switching. Remove explicit lsp.servers.tsc entries as well if you want only ts_ls.

Enable it

-- ~/.config/blak/lua/blak/user.lua
return {
  extras = {
    enabled = {
      "lang.typescript-legacy",
    },
  },
}

You can also enable it from the command line:

:BlakExtras enable lang.typescript-legacy

What it adds

Surface	Contribution
Treesitter	javascript, typescript, tsx, jsdoc, json
Mason	prettier, prettierd
LSP	ts_ls, eslint
Formatting	prettierd, falling back to prettier, for JS/TS/JSON filetypes
Linting	ESLint diagnostics come from the eslint language server

Configure ts_ls and ESLint

Add LSP settings under the server names that the extra registers:

return {
  extras = {
    enabled = { "lang.typescript-legacy" },
  },
  lsp = {
    servers = {
      ts_ls = {
        settings = {
          typescript = {
            inlayHints = {
              includeInlayParameterNameHints = "all",
            },
          },
        },
      },
      eslint = {
        settings = {
          workingDirectory = { mode = "auto" },
        },
      },
    },
  },
}

Project ESLint and Prettier config files still live in the project. Blak only installs and wires the editor tools.

TypeScript SDK and initialization errors

ts_ls wraps TypeScript’s tsserver.js. The language server executable alone is not enough. TypeScript 7 removed that file; the legacy extra needs a compatible SDK that still supplies it.

Before initializing each client, Blak searches the workspace and its ancestors for TypeScript in node_modules, Yarn/pnpm SDKs, or the older PnPify SDK directory. It falls back to the TypeScript bundled with Mason’s typescript-language-server package, using your configured Mason install root. This also lets a project-local language server use Mason’s SDK when it has no TypeScript dependency of its own. Project dependencies are never modified.

If you see “Could not find a valid TypeScript installation”:

1. Run :BlakToolsInstall. Blak refreshes the registry and repairs an installed Mason package if its TypeScript SDK is missing tsserver.js or package metadata.
2. Wait for the installation to finish in :Mason, then restart Neovim.
3. Run :BlakDoctor to check Mason’s fallback and :LspInfo to check the client.

Automatic installation performs the same repair when mason.automatic_install = true. Set it to false for manual tool management. If the registry cannot refresh or the install fails, inspect :MasonLog and retry.

To select an SDK yourself, set lsp.servers.ts_ls.init_options.tsserver.path to the full path of a compatible tsserver.js or its lib directory. Blak preserves explicit path, fallbackPath, and before_init overrides. Remove the override to restore Blak’s SDK resolution. Existing clients need a restart after changing SDKs.

Configure formatting

The extra uses prettierd first and falls back to prettier. If you prefer the plain prettier CLI, define the filetypes yourself in user.lua:

return {
  extras = {
    enabled = { "lang.typescript-legacy" },
  },
  format = {
    formatters_by_ft = {
      javascript = { "prettier" },
      javascriptreact = { "prettier" },
      typescript = { "prettier" },
      typescriptreact = { "prettier" },
      json = { "prettier" },
      jsonc = { "prettier" },
    },
  },
}

Where ESLint diagnostics come from

The extra registers no nvim-lint entries. ESLint diagnostics come from the eslint language server, which Mason installs as vscode-eslint-language-server because the extra lists eslint under lsp.servers.

To run the standalone eslint_d daemon in addition, see Using eslint_d anyway. To take manual control of which servers start, see Disabling automatic enable.

Install and verify

After enabling the extra, run:

:BlakToolsInstall
:BlakTreesitterInstall
:BlakDoctor

Open a TypeScript file and check :LspInfo for ts_ls and eslint.