perf: host pre-compiled filetype mappings (#555)

Generating the filetype mappings by accessing `vim.lsp.config` turns out to be a bad idea because:
1) performance
2) some `lsp/` configurations in nvim-lspconfig execute code immediately (see angularls)
3) accessing `vim.lsp.config[server_name]` seems to populate `:checkhealth vim.lsp`

9 files changed, 403 insertions, 22 deletions

diff --git a/.github/workflows/autogenerate.yml b/.github/workflows/autogenerate.yml
new file mode 100644
index 0000000..a6167ab
--- /dev/null
+++ b/.github/workflows/autogenerate.yml
@@ -0,0 +1,42 @@
+name: Autogenerate code
+
+on:
+    workflow_dispatch:
+    schedule:
+        - cron: "0 10 * * *"
+
+jobs:
+    autogenerate:
+        runs-on: ubuntu-latest
+        steps:
+            - uses: actions/checkout@v2
+            - uses: rhysd/action-setup-vim@v1
+              with:
+                  neovim: true
+                  version: v0.11.0
+
+            - name: make generate
+              run: make generate
+
+            - name: Create Pull Request
+              id: cpr
+              uses: peter-evans/create-pull-request@v4
+              with:
+                  token: ${{ secrets.PAT }}
+                  author: "William Botman <william+bot@redwill.se>"
+                  committer: "William Botman <william+bot@redwill.se>"
+                  add-paths: lua/mason-lspconfig
+                  commit-message: "chore: update generated code"
+                  branch: chore/generate
+                  branch-suffix: short-commit-hash
+                  delete-branch: true
+                  labels: automerge
+                  title: "chore: update generated code"
+
+            - name: Enable Pull Request Automerge
+              if: steps.cpr.outputs.pull-request-operation == 'created'
+              uses: peter-evans/enable-pull-request-automerge@v2
+              with:
+                  token: ${{ secrets.PAT }}
+                  pull-request-number: ${{ steps.cpr.outputs.pull-request-number }}
+                  merge-method: squash
diff --git a/.github/workflows/selene.yml b/.github/workflows/selene.yml
index fb87d50..1486c9c 100644
--- a/.github/workflows/selene.yml
+++ b/.github/workflows/selene.yml
@@ -16,5 +16,5 @@ jobs:
               with:
                   # token is needed because the action allegedly downloads binary from github releases
                   token: ${{ secrets.GITHUB_TOKEN }}
-                  args: lua/ tests/
+                  args: lua/ tests/ scripts/
                   version: 0.25.0
diff --git a/lua/mason-lspconfig/filetype_mappings.lua b/lua/mason-lspconfig/filetype_mappings.lua
new file mode 100644
index 0000000..1db0de6
--- /dev/null
+++ b/lua/mason-lspconfig/filetype_mappings.lua
@@ -0,0 +1,249 @@
+-- THIS FILE IS GENERATED. DO NOT EDIT MANUALLY.
+-- stylua: ignore start
+return {
+  ["BUILD.bazel"] = { "starlark_rust" },
+  OpenFOAM = { "foam_ls" },
+  PKGBUILD = { "pkgbuild_language_server" },
+  antlers = { "antlersls" },
+  arduino = { "arduino_language_server" },
+  asm = { "asm_lsp" },
+  aspnetcorerazor = { "tailwindcss", "htmx" },
+  astro = { "astro", "stylelint_lsp", "tailwindcss", "unocss", "biome", "emmet_ls", "eslint", "htmx" },
+  ["astro-markdown"] = { "tailwindcss", "htmx" },
+  automake = { "autotools_ls" },
+  awk = { "awk_ls" },
+  bash = { "bashls" },
+  bazelrc = { "bazelrc_lsp" },
+  bean = { "beancount" },
+  beancount = { "beancount" },
+  bib = { "ltex_plus", "ltex", "texlab" },
+  bicep = { "bicep" },
+  blade = { "stimulus_ls", "tailwindcss", "htmx" },
+  brs = { "bright_script" },
+  bsl = { "bsl_ls" },
+  bzl = { "bzl", "starlark_rust", "starpls" },
+  c = { "ast_grep", "clangd", "harper_ls" },
+  cairo = { "cairo_ls" },
+  clar = { "clarity_lsp" },
+  clarity = { "clarity_lsp" },
+  clojure = { "tailwindcss", "clojure_lsp", "htmx" },
+  cmake = { "cmake", "neocmake", "harper_ls" },
+  cobol = { "cobol_ls" },
+  comp = { "glsl_analyzer", "glslls" },
+  config = { "autotools_ls" },
+  context = { "ltex_plus", "ltex" },
+  coq = { "coq_lsp" },
+  cpp = { "ast_grep", "clangd", "harper_ls" },
+  crystal = { "crystalline" },
+  cs = { "harper_ls", "csharp_ls", "omnisharp_mono", "omnisharp" },
+  css = { "ast_grep", "stylelint_lsp", "tailwindcss", "unocss", "biome", "emmet_language_server", "emmet_ls", "cssls", "css_variables" },
+  cucumber = { "cucumber_language_server" },
+  cuda = { "clangd" },
+  cue = { "dagger" },
+  cypher = { "cypher_ls" },
+  d = { "serve_d" },
+  dart = { "ast_grep", "harper_ls" },
+  dhall = { "dhall_lsp_server" },
+  ["django-html"] = { "tailwindcss", "htmx" },
+  dockerfile = { "dockerls" },
+  dot = { "dotls" },
+  dts = { "ginko_ls" },
+  dune = { "ocamllsp" },
+  earthfile = { "earthlyls" },
+  edge = { "tailwindcss", "htmx" },
+  edn = { "clojure_lsp" },
+  eelixir = { "tailwindcss", "elixirls", "nextls", "lexical", "htmx" },
+  ejs = { "tailwindcss", "unocss", "htmx" },
+  elixir = { "tailwindcss", "elixirls", "nextls", "lexical", "htmx" },
+  elm = { "elmls" },
+  erb = { "tailwindcss", "unocss", "htmx" },
+  erg = { "erg_language_server" },
+  erlang = { "elp", "erlangls" },
+  eruby = { "stimulus_ls", "tailwindcss", "emmet_language_server", "emmet_ls", "ruby_lsp", "steep", "htmx" },
+  fennel = { "fennel_language_server", "fennel_ls" },
+  flux = { "flux_lsp" },
+  foam = { "foam_ls" },
+  fortran = { "fortls" },
+  frag = { "glsl_analyzer", "glslls" },
+  fsd = { "facility_language_server" },
+  fsharp = { "fsautocomplete" },
+  genie = { "vala_ls" },
+  geom = { "glsl_analyzer", "glslls" },
+  gitcommit = { "ltex_plus", "ltex", "harper_ls" },
+  glsl = { "glsl_analyzer", "glslls" },
+  go = { "ast_grep", "snyk_ls", "harper_ls", "gopls", "golangci_lint_ls" },
+  gohtml = { "tailwindcss", "htmx" },
+  gohtmltmpl = { "tailwindcss", "htmx" },
+  gomod = { "snyk_ls", "gopls", "golangci_lint_ls" },
+  gotmpl = { "gopls" },
+  gowork = { "gopls" },
+  graphql = { "biome", "dprint", "graphql" },
+  groovy = { "groovyls", "gradle_ls" },
+  haml = { "tailwindcss", "unocss", "htmx" },
+  handlebars = { "tailwindcss", "ember", "htmx" },
+  haskell = { "harper_ls", "hls" },
+  hbs = { "tailwindcss", "unocss", "htmx" },
+  heex = { "tailwindcss", "elixirls", "nextls", "lexical", "htmx" },
+  helm = { "snyk_ls", "helm_ls" },
+  hlsl = { "slangd" },
+  hoon = { "hoon_ls" },
+  html = { "ast_grep", "stimulus_ls", "stylelint_lsp", "tailwindcss", "unocss", "emmet_language_server", "emmet_ls", "ltex_plus", "ltex", "lwc_ls", "html", "harper_ls", "angularls", "antlersls", "superhtml", "htmx" },
+  ["html-eex"] = { "tailwindcss", "htmx" },
+  htmlangular = { "tailwindcss", "emmet_language_server", "emmet_ls", "angularls", "htmx" },
+  htmldjango = { "tailwindcss", "emmet_language_server", "emmet_ls", "htmx" },
+  hyprlang = { "hyprls" },
+  jade = { "tailwindcss", "htmx" },
+  java = { "java_language_server", "ast_grep", "jdtls", "harper_ls" },
+  javascript = { "oxlint", "ast_grep", "vtsls", "denols", "tailwindcss", "ts_ls", "unocss", "quick_lint_js", "biome", "ember", "rome", "snyk_ls", "lwc_ls", "harper_ls", "eslint", "dprint", "cssmodules_ls", "htmx" },
+  ["javascript.glimmer"] = { "ember" },
+  ["javascript.jsx"] = { "oxlint", "ast_grep", "vtsls", "denols", "ts_ls", "eslint" },
+  javascriptreact = { "oxlint", "ast_grep", "vtsls", "denols", "tailwindcss", "ts_ls", "unocss", "biome", "emmet_language_server", "emmet_ls", "rome", "eslint", "dprint", "cssmodules_ls", "graphql", "htmx" },
+  jinja = { "jinja_lsp" },
+  jq = { "jqls" },
+  json = { "biome", "rome", "snyk_ls", "jsonls", "spectral", "dprint" },
+  ["json.openapi"] = { "vacuum" },
+  jsonc = { "biome", "jsonls", "dprint" },
+  julia = { "julials" },
+  just = { "just" },
+  kcl = { "kcl" },
+  kotlin = { "ast_grep", "kotlin_language_server" },
+  leaf = { "tailwindcss", "htmx" },
+  less = { "stylelint_lsp", "tailwindcss", "unocss", "emmet_language_server", "emmet_ls", "cssls", "css_variables" },
+  lhaskell = { "hls" },
+  liquid = { "tailwindcss", "shopify_theme_ls", "theme_check", "htmx" },
+  llw = { "lelwel_ls" },
+  lua = { "ast_grep", "emmylua_ls", "lua_ls", "harper_ls" },
+  luau = { "luau_lsp" },
+  mail = { "ltex_plus", "ltex" },
+  make = { "autotools_ls" },
+  markdown = { "tailwindcss", "unocss", "vale_ls", "remark_ls", "zk", "ltex_plus", "ltex", "markdown_oxide", "marksman", "harper_ls", "prosemd_lsp", "dprint", "grammarly", "htmx" },
+  ["markdown.mdx"] = { "marksman" },
+  mdx = { "tailwindcss", "ltex_plus", "mdx_analyzer", "htmx" },
+  menhir = { "ocamllsp" },
+  meson = { "swift_mesonls", "mesonlsp" },
+  ["metamath-zero"] = { "mm0_ls" },
+  motoko = { "motoko_lsp" },
+  move = { "move_analyzer" },
+  mustache = { "tailwindcss", "htmx" },
+  muttrc = { "mutt_ls" },
+  mysql = { "sqlls", "sqls" },
+  ncl = { "nickel_ls" },
+  neomuttrc = { "mutt_ls" },
+  nextflow = { "nextflow_ls" },
+  nginx = { "nginx_language_server" },
+  nickel = { "nickel_ls" },
+  nim = { "nim_langserver", "nimls" },
+  nix = { "nil_ls", "rnix", "harper_ls" },
+  njk = { "tailwindcss", "htmx" },
+  nunjucks = { "tailwindcss", "htmx" },
+  objc = { "clangd" },
+  objcpp = { "clangd" },
+  ocaml = { "ocamllsp" },
+  ocamlinterface = { "ocamllsp" },
+  ocamllex = { "ocamllsp" },
+  odin = { "ols" },
+  opencl = { "opencl_ls" },
+  openscad = { "openscad_lsp" },
+  org = { "ltex_plus", "ltex", "textlsp" },
+  os = { "bsl_ls" },
+  p8 = { "pico8_ls" },
+  pandoc = { "ltex_plus", "ltex" },
+  perl = { "perlnavigator" },
+  pest = { "pest_ls" },
+  php = { "intelephense", "phpactor", "stimulus_ls", "tailwindcss", "unocss", "harper_ls", "psalm", "htmx" },
+  plaintex = { "ltex_plus", "ltex", "texlab" },
+  postcss = { "tailwindcss", "unocss" },
+  prisma = { "prismals" },
+  proto = { "buf_ls", "clangd", "pbls", "protols" },
+  ps1 = { "powershell_es" },
+  pug = { "emmet_language_server", "emmet_ls" },
+  puppet = { "puppet" },
+  purescript = { "purescriptls" },
+  python = { "ast_grep", "basedpyright", "pyre", "pyright", "pylsp", "snyk_ls", "jedi_language_server", "ruff", "harper_ls", "pylyzer", "dprint" },
+  quarto = { "r_language_server", "ltex_plus", "ltex" },
+  query = { "ts_query_ls" },
+  r = { "r_language_server", "air" },
+  raku = { "raku_navigator" },
+  razor = { "tailwindcss", "htmx" },
+  reason = { "tailwindcss", "reason_ls", "ocamllsp", "htmx" },
+  rego = { "regal", "regols" },
+  requirements = { "snyk_ls" },
+  rescript = { "tailwindcss", "unocss", "rescriptls", "htmx" },
+  rmd = { "r_language_server", "ltex_plus", "ltex" },
+  rnoweb = { "ltex_plus", "ltex" },
+  robot = { "robotframework_ls" },
+  roslyn = { "dprint" },
+  rst = { "vale_ls", "ltex_plus", "ltex", "esbonio" },
+  ruby = { "standardrb", "stimulus_ls", "rubocop", "ruby_lsp", "solargraph", "steep", "harper_ls", "sorbet" },
+  rust = { "ast_grep", "unocss", "rust_analyzer", "harper_ls", "dprint" },
+  sass = { "tailwindcss", "unocss", "emmet_language_server", "emmet_ls", "somesass_ls" },
+  scss = { "stylelint_lsp", "tailwindcss", "unocss", "emmet_language_server", "emmet_ls", "somesass_ls", "cssls", "css_variables" },
+  sh = { "bashls" },
+  shaderslang = { "slangd" },
+  slim = { "tailwindcss", "htmx" },
+  slint = { "slint_lsp" },
+  sls = { "salt_ls" },
+  smithy = { "smithy_ls" },
+  sml = { "millet" },
+  solidity = { "solidity_ls", "solang", "solidity", "solidity_ls_nomicfoundation", "solc" },
+  sql = { "sqlls", "sqls", "postgres_lsp" },
+  ss = { "snakeskin_ls" },
+  star = { "starlark_rust" },
+  stylus = { "tailwindcss", "unocss" },
+  sugarss = { "stylelint_lsp", "tailwindcss" },
+  superhtml = { "superhtml" },
+  surface = { "elixirls", "nextls", "lexical" },
+  svelte = { "svelte", "tailwindcss", "unocss", "biome", "emmet_ls", "eslint", "htmx" },
+  svg = { "lemminx" },
+  swift = { "harper_ls" },
+  systemd = { "systemd_ls" },
+  systemverilog = { "svlangserver", "svls", "verible", "hdl_checker" },
+  teal = { "teal_ls" },
+  templ = { "tailwindcss", "html", "htmx", "templ" },
+  terraform = { "terraformls", "snyk_ls", "tflint" },
+  ["terraform-vars"] = { "terraformls", "snyk_ls" },
+  tesc = { "glsl_analyzer", "glslls" },
+  tese = { "glsl_analyzer", "glslls" },
+  tex = { "vale_ls", "ltex_plus", "ltex", "texlab", "textlsp" },
+  text = { "vale_ls", "ltex_plus", "ltex", "textlsp" },
+  thrift = { "thriftls" },
+  toml = { "taplo", "harper_ls", "dprint" },
+  twig = { "tailwindcss", "twiggy_language_server", "htmx" },
+  typescript = { "oxlint", "ast_grep", "vtsls", "denols", "tailwindcss", "ts_ls", "unocss", "quick_lint_js", "biome", "ember", "rome", "snyk_ls", "harper_ls", "eslint", "dprint", "cssmodules_ls", "angularls", "htmx" },
+  ["typescript.glimmer"] = { "ember" },
+  ["typescript.tsx"] = { "oxlint", "ast_grep", "vtsls", "denols", "ts_ls", "biome", "rome", "eslint", "angularls" },
+  typescriptreact = { "oxlint", "ast_grep", "vtsls", "denols", "tailwindcss", "ts_ls", "unocss", "biome", "emmet_language_server", "emmet_ls", "rome", "harper_ls", "eslint", "dprint", "cssmodules_ls", "graphql", "angularls", "htmx" },
+  typespec = { "tsp_server" },
+  typst = { "ltex_plus", "tinymist", "harper_ls" },
+  v = { "v_analyzer", "vls" },
+  vala = { "vala_ls" },
+  vb = { "omnisharp_mono", "omnisharp" },
+  verilog = { "svlangserver", "svls", "verible", "hdl_checker" },
+  vert = { "glsl_analyzer", "glslls" },
+  veryl = { "veryl_ls" },
+  vhd = { "vhdl_ls" },
+  vhdl = { "vhdl_ls", "hdl_checker" },
+  vim = { "vimls" },
+  visualforce = { "visualforce_ls" },
+  vlang = { "vls" },
+  vmasm = { "asm_lsp" },
+  vsh = { "v_analyzer" },
+  vue = { "vuels", "volar", "stylelint_lsp", "tailwindcss", "unocss", "biome", "emmet_ls", "eslint", "htmx" },
+  ["vue-html"] = { "unocss" },
+  vv = { "v_analyzer" },
+  wgsl = { "wgsl_analyzer" },
+  wxss = { "stylelint_lsp" },
+  xhtml = { "ltex_plus", "ltex" },
+  xml = { "lemminx" },
+  xsd = { "lemminx" },
+  xsl = { "lemminx" },
+  xslt = { "lemminx" },
+  yaml = { "azure_pipelines_ls", "gh_actions_ls", "yamlls", "snyk_ls", "spectral", "hydra_lsp" },
+  ["yaml.ansible"] = { "ansiblels" },
+  ["yaml.docker-compose"] = { "docker_compose_language_service", "yamlls" },
+  ["yaml.gitlab"] = { "gitlab_ci_ls", "yamlls" },
+  ["yaml.openapi"] = { "vacuum" },
+  yml = { "spectral" },
+  zig = { "zls" },
+  zir = { "zls" }
+}
\ No newline at end of file
diff --git a/lua/mason-lspconfig/mappings.lua b/lua/mason-lspconfig/mappings.lua
index 2523aed..c40853f 100644
--- a/lua/mason-lspconfig/mappings.lua
+++ b/lua/mason-lspconfig/mappings.lua
@@ -20,22 +20,7 @@ function M.get_mason_map()
 end
 
 function M.get_filetype_map()
-    local server_names = vim.tbl_keys(M.get_mason_map().lspconfig_to_package)
-
-    ---@type table<string, string[]>
-    local filetype_map = {}
-    for _, server_name in ipairs(server_names) do
-        local filetypes = vim.tbl_get(vim.lsp.config, server_name, "filetypes")
-        if filetypes then
-            for _, filetype in ipairs(filetypes) do
-                if not filetype_map[filetype] then
-                    filetype_map[filetype] = {}
-                end
-                table.insert(filetype_map[filetype], server_name)
-            end
-        end
-    end
-    return filetype_map
+    return require "mason-lspconfig.filetype_mappings"
 end
 
 function M.get_all()
diff --git a/scripts/lua/mason-scripts/mason-lspconfig/generate.lua b/scripts/lua/mason-scripts/mason-lspconfig/generate.lua
new file mode 100644
index 0000000..75584aa
--- /dev/null
+++ b/scripts/lua/mason-scripts/mason-lspconfig/generate.lua
@@ -0,0 +1,42 @@
+local Optional = require "mason-core.optional"
+
+local _ = require "mason-core.functional"
+local a = require "mason-core.async"
+local path = require "mason-core.path"
+local script_utils = require "mason-scripts.utils"
+
+local MASON_LSPCONFIG_DIR = path.concat { "lua", "mason-lspconfig" }
+
+require("mason").setup()
+local registry = require "mason-registry"
+registry.refresh()
+
+---@async
+local function create_lspconfig_filetype_map()
+    local lspconfig_servers =
+        _.filter_map(_.compose(Optional.of_nilable, _.path { "neovim", "lspconfig" }), registry.get_all_package_specs())
+    ---@type table<string, string[]>
+    local filetype_map = {}
+
+    for _, server_name in ipairs(lspconfig_servers) do
+        local filetypes = vim.tbl_get(vim.lsp.config, server_name, "filetypes")
+        if filetypes then
+            for _, filetype in ipairs(filetypes) do
+                if not filetype_map[filetype] then
+                    filetype_map[filetype] = {}
+                end
+                table.insert(filetype_map[filetype], server_name)
+            end
+        end
+    end
+
+    script_utils.write_file(
+        path.concat { MASON_LSPCONFIG_DIR, "filetype_mappings.lua" },
+        "return " .. vim.inspect(filetype_map),
+        "w"
+    )
+end
+
+a.run_blocking(function()
+    create_lspconfig_filetype_map()
+end)
diff --git a/scripts/lua/mason-scripts/utils.lua b/scripts/lua/mason-scripts/utils.lua
new file mode 100644
index 0000000..ee6ab10
--- /dev/null
+++ b/scripts/lua/mason-scripts/utils.lua
@@ -0,0 +1,40 @@
+local _ = require "mason-core.functional"
+local fs = require "mason-core.fs"
+
+local M = {}
+
+---@async
+---@param path string
+---@param contents string
+---@param flags string?
+function M.write_file(path, contents, flags)
+    local header = _.cond({
+        {
+            _.matches "%.lua$",
+            _.always {
+                "-- THIS FILE IS GENERATED. DO NOT EDIT MANUALLY.",
+                "-- stylua: ignore start",
+            },
+        },
+        {
+            _.matches "%.md$",
+            _.always {
+                "<!--- THIS FILE IS GENERATED. DO NOT EDIT MANUALLY. -->",
+            },
+        },
+        {
+            _.matches "doc/.+%.txt$",
+            _.always {},
+        },
+        {
+            _.T,
+            _.always {
+                "# THIS FILE IS GENERATED. DO NOT EDIT MANUALLY.",
+            },
+        },
+    }, path)
+
+    fs.async.write_file(path, table.concat(_.concat(header, { contents }), "\n"), flags)
+end
+
+return M
diff --git a/scripts/nvim.sh b/scripts/nvim.sh
new file mode 100755
index 0000000..c2dcb6b
--- /dev/null
+++ b/scripts/nvim.sh
@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+
+set -exuo pipefail
+
+declare -x DEPENDENCIES="${PWD}/dependencies"
+declare -x MASON_DIR="$PWD"
+declare -x MASON_SCRIPT_DIR="${PWD}/scripts"
+
+nvim -u NONE -E -R --headless \
+  --cmd "set rtp^=${MASON_SCRIPT_DIR},${MASON_DIR}" \
+  --cmd "set packpath^=${DEPENDENCIES}" \
+  --cmd "packloadall" \
+  --cmd "luafile $1" \
+  --cmd "q"
diff --git a/tests/mason-lspconfig/api/api_spec.lua b/tests/mason-lspconfig/api/api_spec.lua
index 53b3a27..e0a189e 100644
--- a/tests/mason-lspconfig/api/api_spec.lua
+++ b/tests/mason-lspconfig/api/api_spec.lua
@@ -1,4 +1,7 @@
+local stub = require "luassert.stub"
+
 local _ = require "mason-core.functional"
+local mappings = require "mason-lspconfig.mappings"
 local mason_lspconfig = require "mason-lspconfig"
 
 describe("mason-lspconfig API", function()
@@ -16,6 +19,10 @@ describe("mason-lspconfig API", function()
     end)
 
     it("should return all available servers for given filetype", function()
+        stub(mappings, "get_filetype_map", {
+            ["dummylang"] = { "dummylsp" },
+        })
+
         assert.same(
             { "dummylsp" },
             _.sort_by(
@@ -28,11 +35,9 @@ describe("mason-lspconfig API", function()
     end)
 
     it("should return all available servers for given filetypes", function()
-        vim.lsp.config("dummylsp", {
-            filetypes = { "dummylang" },
-        })
-        vim.lsp.config("dummy2lsp", {
-            filetypes = { "madeuplang" },
+        stub(mappings, "get_filetype_map", {
+            ["dummylang"] = { "dummylsp" },
+            ["madeuplang"] = { "dummy2lsp" },
         })
         assert.same(
             { "dummy2lsp", "dummylsp" },
diff --git a/tests/mason-lspconfig/api/command_spec.lua b/tests/mason-lspconfig/api/command_spec.lua
index 3cd6679..7b39c59 100644
--- a/tests/mason-lspconfig/api/command_spec.lua
+++ b/tests/mason-lspconfig/api/command_spec.lua
@@ -4,6 +4,7 @@ local stub = require "luassert.stub"
 
 local Pkg = require "mason-core.package"
 local api = require "mason-lspconfig.api.command"
+local mappings = require "mason-lspconfig.mappings"
 local registry = require "mason-registry"
 
 describe(":LspInstall", function()
@@ -23,6 +24,9 @@ describe(":LspInstall", function()
             local dummy = registry.get_package "dummy"
             spy.on(Pkg, "install")
             stub(vim.ui, "select")
+            stub(mappings, "get_filetype_map", {
+                ["dummylang"] = { "dummylsp" },
+            })
             vim.ui.select.invokes(function(items, opts, callback)
                 callback "dummylsp"
             end)