neotest-jest

This plugin provides a jest adapter for the Neotest framework. Requires at least Neotest version 4.0.0 which in turn requires at least neovim version 0.9.0.

It is currently a work in progress.

Installation

Using packer:

use({
  "nvim-neotest/neotest",
  requires = {
    ...,
    "nvim-neotest/neotest-jest",
  }
  config = function()
    require("neotest").setup({
      ...,
      adapters = {
        require("neotest-jest")({
          jestCommand = "npm test --",
          jestArguments = function(defaultArguments, context)
            return defaultArguments
          end,
          jestConfigFile = "custom.jest.config.ts",
          env = { CI = true },
          cwd = function(path)
            return vim.fn.getcwd()
          end,
          isTestFile = require("neotest-jest.jest-util").defaultIsTestFile,
        }),
      }
    })
  end
})

Make sure you have the appropriate treesitter language parsers installed otherwise no tests will be found:

:TSInstall javascript

You might want to install tsx and typescript parser as well depending on your project.

Configuration

jestCommand

Type: string | fun(path: string): string

The jest command to run when running tests. Can also be a function that accepts the path to the current neotest position and returns the command to run. neotest-jest will attempt to resolve it automatically if not given.

• Example: "npm test --"

jestArguments

Type: fun(defaultArguments: string[], jestArgsContext: neotest-jest.JestArgumentContext): string[]

The arguments to pass to jest when running tests.

The function is called with the default arguments and a context table that contains a config: string? entry for the config file (normally passed to the --config option) or nil if none was found, a resultsPath entry for the destination file for writing json test output (normally passed to the --outputFile option), and a testNamePattern entry for the regex pattern for tests (normally passed to the --testNamePattern option). It should return the final arguments as a string[].

Warning

Make sure to always pass the following options:

• --forceExit: Ensure jest and thus the adapter does not hang
• --testLocationInResults: Ensure jest outputs test locations
• --json: Output test results in json
• --outputFile: The location for writing json output

The default function for jestArguments can be obtained by calling require("neotest-jest.jest-util").getJestArguments. The test file is automatically added to the end of the jest arguments by neotest-jest.

jestConfigFile

Type: string | fun(file_path: string): string

Path to a jest config file or a function taking the path of the current neotest position and returning a path to a jest config file. Defaults to "jest.config.js".

• Example: "custom.jest.ts"

env

Type: table<string, string> | fun(): table<string, string>

A key-value map of environment variables to set or a function returning such a map.

• Example: { CI = true }

cwd

Type: string | fun(): string

The current working directory to use or a function returning the current working directory.

• Example: function() return vim.fn.getcwd() end

strategy_config

The nvim-dap strategy configuration to use when debugging tests.

jest_test_discovery

Whether to discover parametrized tests such as those run with it.each/test.each. See Parameterized tests for more info.

• Example: jest_test_discovery = true

isTestFile

If set, overrides the check for determining if a file is a test file or not. The default behaviour will match the file path with a predefined set of patterns and require jest to be installed as a dependency via dependencies or devDependencies, or if a value in scripts is exactly 'jest' in the package.json.

Warning

The isTestFile function runs in an async context so you cannot call functions that cannot be called in fast events (see :h vim.in_fast_event())

Example:

---@async
---@param file_path string?
---@return boolean
isTestFile = function(file_path)
  if not file_path then
    return false
  end

  return vim.fn.fnamemodify(file_path, ":e:e") == "testy.js"
end

You can access the default isTestFile function via require("neotest-jest.jest-util").defaultIsTestFile, the default test file matcher via require("neotest-jest.util").defaultTestFileMatcher, and the default check for a jest dependency via require("neotest-jest.jest-util").hasJestDependency

Usage

See neotest's documentation for more information on how to run tests.

Running tests in watch mode

jest allows to run your tests in watch mode. To run test in this mode you either can enable it globally in the setup:

require('neotest').setup({
  ...,
  adapters = {
    require('neotest-jest')({
      jestCommand = require('neotest-jest.jest-util').getJestCommand(vim.fn.expand '%:p:h') .. ' --watch',
    }),
  }
})

or add a specific keymap to run tests with watch mode:

vim.api.nvim_set_keymap("n", "<leader>tw", "<cmd>lua require('neotest').run.run({ jestCommand = 'jest --watch ' })<cr>", {})

Parameterized tests

If you want to allow to neotest-jest to discover parameterized tests you need to enable flag jest_test_discovery in config setup:

require('neotest').setup({
  ...,
  adapters = {
    require('neotest-jest')({
      ...,
      jest_test_discovery = false,
    }),
  }
})

Its also recommended to disable neotest discovery option like this:

require("neotest").setup({
	...,
	discovery = {
		enabled = false,
	},
})

because jest_test_discovery runs jest command on file to determine what tests are inside the file. If discovery would be enabled then neotest-jest would spawn a lot of procesees.

Monorepos

If you have a monorepo setup, you might have to do a little more configuration, especially if you have different jest configurations per package.

jestConfigFile = function(file)
  if file:find("/packages/") then
    -- Matches "some/path/" in "some/path/src/"
    local match = file:match("(.*/[^/]+/)src")

    if match then
      return match .. "jest.config.ts"
    end
  end

  return vim.fn.getcwd() .. "/jest.config.ts"
end,

Also, if your monorepo set up requires you to run a specific test file with cwd on the package directory (like when you have a lerna setup for example), you might also have to tweak things a bit:

cwd = function(file)
  if file:find("/packages/") then
    -- Matches "some/path/" in "some/path/src/"
    local match = file:match("(.*/[^/]+/)src")

    if match then
      return match
    end
  end

  return vim.fn.getcwd()
end

🎁 Contributing

Please raise a PR if you are interested in adding new functionality or fixing any bugs. When submitting a bug, please include an example spec that can be tested.

To run the tests and styling:

1. Fork this repository.
2. Make changes.
3. Make sure tests and styling checks are passing. You will need to install jest and make sure it is available as a command in order to run the tests since it tests parametrized tests which require running a jest command. It should suffice to run npm install in the ./spec directory.
   • Run tests by running ./scripts/test in the root directory. Running the tests requires plenary.nvim. You may need to update the paths in ./tests/minimal_init.lua to point to your local installation.
   • If you are testing a new feature that requires running tests then please run cd spec/, open a test file, and make sure things work.
   • Install stylua and check styling using stylua --check lua/ tests/. Omit --check in order to fix styling.
4. Submit a pull request.
5. Get it approved.

Bug Reports

Please file any bug reports and I might take a look if time permits otherwise please submit a PR, this plugin is intended to be by the community for the community.