Elixir LSP Fails to Start

I’m seeing the following error using the latest version of coc-elixir:

12:28:30.454 [error] GenServer ElixirLS.LanguageServer.Server terminating
** (Mix.Error) Unknown dependency :ecto given to :import_deps in the formatter configuration. The dependency is not listed in your mix.exs for environment :prod
    (mix 1.10.4) lib/mix.ex:392: Mix.raise/1
    (mix 1.10.4) lib/mix/tasks/format.ex:246: anonymous fn/3 in Mix.Tasks.Format.eval_deps_opts/2
    (elixir 1.10.4) lib/enum.ex:2111: Enum."-reduce/3-lists^foldl/2-0-"/3
    (mix 1.10.4) lib/mix/tasks/format.ex:245: Mix.Tasks.Format.eval_deps_opts/2
    (mix 1.10.4) lib/mix/tasks/format.ex:201: anonymous fn/5 in Mix.Tasks.Format.eval_deps_and_subdirectories/4
    (mix 1.10.4) lib/mix/tasks/format.ex:210: Mix.Tasks.Format.maybe_cache_in_manifest/3
    (mix 1.10.4) lib/mix/tasks/format.ex:160: Mix.Tasks.Format.formatter_opts_for_file/2
    (language_server 0.5.0) lib/language_server/server.ex:487: ElixirLS.LanguageServer.Server.handle_request/2
Last message: {:"$gen_cast", {:receive_packet, %{"id" => 132, "jsonrpc" => "2.0", "method" => "textDocument/completion", "params" => %{"context" => %{"triggerKind" => 3}, "position" => %{"character" => 11, "line" => 183}, "textDocument" => %{"uri" => "file:///Users/james/Projects/rovr_api/test/rovr_api_web/controllers/read_receipt_controller_test.exs"}}}}}
State: %ElixirLS.LanguageServer.Server{analysis_ready?: false, awaiting_contracts: [], build_diagnostics: [], build_ref: #Reference<0.1375640648.712245250.125063>, build_running?: true, client_capabilities: %{"textDocument" => %{"codeAction" => %{"codeActionLiteralSupport" => %{"codeActionKind" => %{"valueSet" => ["", "quickfix", "refactor", "refactor.extract", "refactor.inline", "refactor.rewrite", "source", "source.organizeImports"]}}, "dynamicRegistration" => true, "isPreferredSupport" => true}, "codeLens" => %{"dynamicRegistration" => true}, "colorProvider" => %{"dynamicRegistration" => true}, "completion" => %{"completionItem" => %{"commitCharactersSupport" => true, "deprecatedSupport" => true, "documentationFormat" => ["markdown", "plaintext"], "preselectSupport" => true, "snippetSupport" => true}, "completionItemKind" => %{"valueSet" => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25]}, "contextSupport" => true, "dynamicRegistration" => true}, "declaration" => %{"dynamicRegistration" => true}, "definition" => %{"dynamicRegistration" => true}, "documentHighlight" => %{"dynamicRegistration" => true}, "documentLink" => %{"dynamicRegistration" => true, "tooltipSupport" => true}, "documentSymbol" => %{"dynamicRegistration" => true, "hierarchicalDocumentSymbolSupport" => true, "symbolKind" => %{"valueSet" => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26]}, "tagSupport" => %{"valueSet" => [1]}}, "foldingRange" => %{"dynamicRegistration" => true, "lineFoldingOnly" => true, "rangeLimit" => 5000}, "formatting" => %{"dynamicRegistration" => true}, "hover" => %{"contentFormat" => ["markdown", "plaintext"], "dynamicRegistration" => true}, "implementation" => %{"dynamicRegistration" => true}, "onTypeFormatting" => %{"dynamicRegistration" => true}, "publishDiagnostics" => %{"relatedInformation" => true, "tagSupport" => %{"valueSet" => [1, 2]}, "versionSupport" => false}, "rangeFormatting" => %{"dynamicRegistration" => true}, "references" => %{"dynamicRegistration" => true}, "rename" => %{"dynamicRegistration" => true, "prepareSupport" => true}, "selectionRange" => %{"dynamicRegistration" => true}, "signatureHelp" => %{"dynamicRegistration" => true, "signatureInformation" => %{"documentationFormat" => ["markdown", "plaintext"], "parameterInformation" => %{"labelOffsetSupport" => true}}}, "synchronization" => %{"didSave" => true, "dynamicRegistration" => true, "willSave" => true, "willSaveWaitUntil" => true}, "typeDefinition" => %{"dynamicRegistration" => true}}, "window" => %{"workDoneProgress" => true}, "workspace" => %{"applyEdit" => true, "configuration" => true, "didChangeConfiguration" => %{"dynamicRegistration" => true}, "didChangeWatchedFiles" => %{"dynamicRegistration" => true}, "executeCommand" => %{"dynamicRegistration" => true}, "symbol" => %{"dynamicRegistration" => true, "symbolKind" => %{"valueSet" => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26]}, "tagSupport" => %{"valueSet" => [1]}}, "workspaceEdit" => %{"documentChanges" => true, "failureHandling" => "textOnlyTransactional", "resourceOperations" => ["create", "rename", "delete"]}, "workspaceFolders" => true}}, dialyzer_diagnostics: [], dialyzer_sup: #PID<0.124.0>, load_all_modules?: false, needs_build?: false, project_dir: "/Users/james/Projects/rovr_api", received_shutdown?: false, requests: %{}, root_uri: "file:///Users/james/Projects/rovr_api", server_instance_id: "OVfDHNaNPl1v2L2pm7StSX_IPTWne1P2", settings: %{"dialyzerEnabled" => true, "dialyzerFormat" => "dialyzer", "dialyzerWarnOpts" => [], "fetchDeps" => true, "mixEnv" => "test", "suggestSpecs" => true}, source_files: %{"file:///Users/james/Projects/rovr_api/lib/rovr_api/accounts/user.ex" => %ElixirLS.LanguageServer.SourceFile{dirty?: false, text: "defmodule RovrApi.Accounts.User do\n  @moduledoc \"\"\"\n  User data\n  \"\"\"\n\n  use Ecto.Schema\n  import Ecto.Changeset\n\n  alias RovrApi.Subscriptions.Subscription\n\n  @type t :: %__MODULE__{\n          id: String.t() | nil,\n          email: String.t() | nil,\n          confirmed_at: NaiveDateTime.t() | nil,\n          hashed_password: String.t() | nil,\n          inserted_at: NaiveDateTime.t() | nil,\n          updated_at: NaiveDateTime.t() | nil\n        }\n\n  @derive {Inspect, except: [:password]}\n  @primary_key {:id, :binary_id, autogenerate: true}\n  @foreign_key_type :binary_id\n  schema \"users\" do\n    field :email, :string\n    field :password, :string, virtual: true\n    field :hashed_password, :string\n    field :confirmed_at, :naive_datetime\n\n    has_many :subscriptions, Subscription\n\n    has_many :feeds, through: [:subscriptions, :feeds]\n\n    timestamps()\n  end\n\n  @doc \"\"\"\n  A user changeset for registration.\n\n  It is important to validate the length of both e-mail and password.\n  Otherwise databases may truncate the e-mail without warnings, which\n  could lead to unpredictable or insecure behaviour. Long passwords may\n  also be very expensive to hash for certain algorithms.\n  \"\"\"\n  @spec registration_changeset(t(), map()) :: Ecto.Changeset.t()\n  def registration_changeset(%__MODULE__{} = user, attrs) do\n    user\n    |> cast(attrs, [:email, :password])\n    |> validate_email()\n    |> validate_password()\n  end\n\n  defp validate_email(changeset) do\n    changeset\n    |> validate_required([:email])\n    |> validate_format(:email, ~r/^[^\\s]+@[^\\s]+$/, message: \"must have the @ sign and no spaces\")\n    |> validate_length(:email, max: 160)\n    |> unsafe_validate_unique(:email, RovrApi.Repo)\n    |> unique_constraint(:email)\n  end\n\n  defp validate_password(changeset) do\n    changeset\n    |> validate_required([:password])\n    |> validate_length(:password, min: 12, max: 80)\n    # |> validate_format(:password, ~r/[a-z]/, message: \"at least one lower case character\")\n    # |> validate_format(:password, ~r/[A-Z]/, message: \"at least one upper case character\")\n    # |> validate_format(:password, ~r/[!?@#$%^&*_0-9]/, message: \"at least one digit or punctuation character\")\n    |> prepare_changes(&hash_password/1)\n  end\n\n  defp hash_password(changeset) do\n    password = get_change(changeset, :password)\n\n    changeset\n    |> put_change(:hashed_password, Bcrypt.hash_pwd_salt(password))\n    |> delete_change(:password)\n  end\n\n  @doc \"\"\"\n  A user changeset for changing the e-mail.\n\n  It requires the e-mail to change otherwise an error is added.\n  \"\"\"\n  @spec email_changeset(t(), map()) :: Ecto.Changeset.t()\n  def email_changeset(%__MODULE__{} = user, attrs) do\n    user\n    |> cast(attrs, [:email])\n    |> validate_email()\n    |> case do\n      %{changes: %{email: _}} = changeset -> changeset\n      %{} = changeset -> (truncated)
[Warn  - 12:28:30 p.m.] ** (exit) exited in: GenServer.call(ElixirLS.LanguageServer.JsonRpc, {:packet, %{"jsonrpc" => "2.0", "method" => "textDocument/didChange", "params" => %{"contentChanges" => [%{"range" => %{"end" => %{"character" => 11, "line" => 183}, "start" => %{"character" => 11, "line" => 183}}, "rangeLength" => 0, "text" => "t"}], "textDocument" => %{"uri" => "file:///Users/james/Projects/rovr_api/test/rovr_api_web/controllers/read_receipt_controller_test.exs", "version" => 308}}}}, 5000)
    ** (EXIT) no process: the process is not alive or there's no process currently associated with the given name, possibly because its application isn't started
    (elixir 1.10.4) lib/gen_server.ex:1013: GenServer.call/3
    (elixir 1.10.4) lib/stream.ex:441: anonymous fn/4 in Stream.each/2
    (elixir 1.10.4) lib/stream.ex:1449: Stream.do_element_resource/6
    (elixir 1.10.4) lib/stream.ex:1609: Enumerable.Stream.do_each/4
    (elixir 1.10.4) lib/stream.ex:649: Stream.run/1
    (stdlib 3.13) erl_eval.erl:680: :erl_eval.do_apply/6
[Error  - 12:28:33 p.m.] /Users/james/dotfiles/config/coc/extensions/node_modules/coc-elixir/els-release/language_server.sh exited with code: 1
[Info  - 12:28:33 p.m.] Connection to server got closed. Server will restart.
[Error  - 12:28:33 p.m.] Request textDocument/completion failed.
Error: Connection got disposed.
    at Object.dispose (/Users/james/.vim/plugged/coc.nvim/build/index.js:17340:25)
    at Object.dispose (/Users/james/.vim/plugged/coc.nvim/build/index.js:58035:35)
    at LanguageClient.handleConnectionClosed (/Users/james/.vim/plugged/coc.nvim/build/index.js:60344:42)
    at LanguageClient.handleConnectionClosed (/Users/james/.vim/plugged/coc.nvim/build/index.js:57647:15)
    at closeHandler (/Users/james/.vim/plugged/coc.nvim/build/index.js:60330:18)
    at CallbackList.invoke (/Users/james/.vim/plugged/coc.nvim/build/index.js:17980:39)
    at Emitter.fire (/Users/james/.vim/plugged/coc.nvim/build/index.js:18039:36)
    at closeHandler (/Users/james/.vim/plugged/coc.nvim/build/index.js:16676:26)
    at CallbackList.invoke (/Users/james/.vim/plugged/coc.nvim/build/index.js:17980:39)
    at Emitter.fire (/Users/james/.vim/plugged/coc.nvim/build/index.js:18039:36)
[Error  - 12:28:33 p.m.] Request textDocument/completion failed.
Error: Connection got disposed.
    at Object.dispose (/Users/james/.vim/plugged/coc.nvim/build/index.js:17340:25)
    at Object.dispose (/Users/james/.vim/plugged/coc.nvim/build/index.js:58035:35)
    at LanguageClient.handleConnectionClosed (/Users/james/.vim/plugged/coc.nvim/build/index.js:60344:42)
    at LanguageClient.handleConnectionClosed (/Users/james/.vim/plugged/coc.nvim/build/index.js:57647:15)
    at closeHandler (/Users/james/.vim/plugged/coc.nvim/build/index.js:60330:18)
    at CallbackList.invoke (/Users/james/.vim/plugged/coc.nvim/build/index.js:17980:39)
    at Emitter.fire (/Users/james/.vim/plugged/coc.nvim/build/index.js:18039:36)
    at closeHandler (/Users/james/.vim/plugged/coc.nvim/build/index.js:16676:26)
    at CallbackList.invoke (/Users/james/.vim/plugged/coc.nvim/build/index.js:17980:39)
    at Emitter.fire (/Users/james/.vim/plugged/coc.nvim/build/index.js:18039:36)
[Error  - 12:28:33 p.m.] Request textDocument/completion failed.
Error: Connection got disposed.
    at Object.dispose (/Users/james/.vim/plugged/coc.nvim/build/index.js:17340:25)
    at Object.dispose (/Users/james/.vim/plugged/coc.nvim/build/index.js:58035:35)
    at LanguageClient.handleConnectionClosed (/Users/james/.vim/plugged/coc.nvim/build/index.js:60344:42)
    at LanguageClient.handleConnectionClosed (/Users/james/.vim/plugged/coc.nvim/build/index.js:57647:15)
    at closeHandler (/Users/james/.vim/plugged/coc.nvim/build/index.js:60330:18)
    at CallbackList.invoke (/Users/james/.vim/plugged/coc.nvim/build/index.js:17980:39)
    at Emitter.fire (/Users/james/.vim/plugged/coc.nvim/build/index.js:18039:36)
    at closeHandler (/Users/james/.vim/plugged/coc.nvim/build/index.js:16676:26)
    at CallbackList.invoke (/Users/james/.vim/plugged/coc.nvim/build/index.js:17980:39)
    at Emitter.fire (/Users/james/.vim/plugged/coc.nvim/build/index.js:18039:36)
Started ElixirLS v0.5.0
Elixir version: "1.10.4 (compiled with Erlang/OTP 23)"
Erlang version: "23"
ElixirLS compiled with Elixir 1.10.3 and erlang 23
MIX_ENV: test
MIX_TARGET: host
Resolving Hex dependencies...
Dependency resolution completed:
Unchanged:
  bcrypt_elixir 2.2.0
  bodyguard 2.4.0
  bunt 0.2.0
  castore 0.1.6
  certifi 2.5.1
  combine 0.10.0
  comeonin 5.3.1
  connection 1.0.4
  cors_plug 2.0.2
  cowboy 2.8.0
  cowlib 2.9.1
  credo 1.4.0
  db_connection 2.2.2
  decimal 1.8.1
  dialyxir 1.0.0
  ecto 3.4.4
  ecto_sql 3.4.4
  elixir_make 0.6.0
  erlex 0.2.6
  feeder 2.3.2
  feeder_ex 1.1.0
  floki 0.26.0
  gettext 0.18.0
  hackney 1.15.2
  html_entities 0.5.1
  idna 6.0.0
  jason 1.2.1
  jsonapi 1.3.0
  metrics 1.0.1
  mime 1.3.1
  mimerl 1.2.0
  mint 1.1.0
  oban 2.0.0-rc.3
  parse_trans 3.3.0
  phoenix 1.5.3
  phoenix_ecto 4.1.0
  phoenix_html 2.14.2
  phoenix_live_dashboard 0.2.6
  phoenix_live_view 0.13.3
  phoenix_pubsub 2.0.0
  phx_gen_auth 0.4.0
  plug 1.10.3
  plug_cowboy 2.3.0
  plug_crypto 1.1.2
  postgrex 0.15.5
  ranch 1.7.1
  sentry 7.2.4
  sobelow 0.10.3
  ssl_verify_fun 1.1.5
  telemetry 0.4.1
  telemetry_metrics 0.5.0
  telemetry_poller 0.5.0
  tesla 1.3.3
  timex 3.6.2
  tzdata 1.0.3
  unicode_util_compat 0.4.1
All dependencies are up to date
==> ecto_sql
Compiling 26 files (.ex)
Generated ecto_sql app
==> oban
Compiling 20 files (.ex)
Generated oban app
==> plug_crypto
Compiling 5 files (.ex)
Generated plug_crypto app
==> plug
Compiling 1 file (.erl)
Compiling 40 files (.ex)
[Warn  - 12:28:45 p.m.] warning: System.stacktrace/0 outside of rescue/catch clauses is deprecated. If you want to support only Elixir v1.7+, you must access __STACKTRACE__ inside a rescue/catch. If you want to support earlier Elixir versions, move System.stacktrace/0 inside a rescue/catch
  lib/plug/conn/wrapper_error.ex:23

Generated plug app
==> bodyguard
Compiling 9 files (.ex)
[Warn  - 12:28:49 p.m.] warning: function actions/1 required by protocol Plug.Exception is not implemented (in module Plug.Exception.Bodyguard.NotAuthorizedError)
  lib/bodyguard/not_authorized_error.ex:8: Plug.Exception.Bodyguard.NotAuthorizedError (module)

Generated bodyguard app
==> cors_plug
Compiling 1 file (.ex)
Generated cors_plug app
==> jsonapi
Compiling 21 files (.ex)
Generated jsonapi app
==> plug_cowboy
Compiling 6 files (.ex)
Generated plug_cowboy app
==> phoenix_html
Compiling 8 files (.ex)
Generated phoenix_html app
==> phoenix
Compiling 66 files (.ex)
Generated phoenix app
==> sentry
Compiling 14 files (.ex)
Generated sentry app
==> phoenix_live_view
Compiling 18 files (.ex)
Generated phoenix_live_view app
==> phoenix_live_dashboard
Compiling 33 files (.ex)
Generated phoenix_live_dashboard app
==> phoenix_ecto
Compiling 7 files (.ex)

In a previous session the :ecto dependency was something else entirely.

[heimann]

@heimann i solved it by building from source

here’s the coc-elixir guide but i guess it might work for vscode too https://github.com/elixir-lsp/coc-elixir#troubleshooting

so i’m guessing coc-elixir might need to be built with a newer version of elixir/otp. i would be careful of otp 23 though, as it breaks a few libraries

Worked for me by upgrading to OTP 23 but yes, OTP 23 does break a lot of libs so I had to do some cascading updates across the board (because of deprecating of SSL 3.0 which tbh is a very good idea anyway 😃 ).

[dylan-chong]

@heimann i solved it by building from source

here’s the coc-elixir guide but i guess it might work for vscode too https://github.com/elixir-lsp/coc-elixir#troubleshooting

so i’m guessing coc-elixir might need to be built with a newer version of elixir/otp. i would be careful of otp 23 though, as it breaks a few libraries