From e622ef4f96090dee15adcd91eb5a2645e45cfc04 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jonatan=20K=C5=82osko?= <jonatanklosko@gmail.com>
Date: Fri, 3 Feb 2023 18:30:41 +0100
Subject: [PATCH] Fix dialyzer warnings (#1691)

---
 lib/livebook/application.ex              | 2 ++
 lib/livebook/config.ex                   | 2 +-
 lib/livebook/notebook/cell/code.ex       | 2 +-
 lib/livebook/notebook/cell/markdown.ex   | 2 +-
 lib/livebook/notebook/cell/smart.ex      | 6 +++---
 lib/livebook/settings/env_var.ex         | 4 ++--
 mix.exs                                  | 2 ++
 test/support/test_modules/bad_inspect.ex | 2 ++
 8 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/lib/livebook/application.ex b/lib/livebook/application.ex
index 87bacbd05..54a77cf12 100644
--- a/lib/livebook/application.ex
+++ b/lib/livebook/application.ex
@@ -254,6 +254,8 @@ defmodule Livebook.Application do
     end
   end
 
+  @dialyzer {:no_return, iframe_port_in_use: 1}
+
   defp iframe_port_in_use(port) do
     Livebook.Config.abort!(
       "Failed to start Livebook iframe server because port #{port} is already in use"
diff --git a/lib/livebook/config.ex b/lib/livebook/config.ex
index 5d2984510..beab92514 100644
--- a/lib/livebook/config.ex
+++ b/lib/livebook/config.ex
@@ -132,7 +132,7 @@ defmodule Livebook.Config do
   @doc """
   Returns an mfa if there's a way to shut down the system.
   """
-  @spec shutdown_callback() :: mfa() | nil
+  @spec shutdown_callback() :: {module(), atom(), list()} | nil
   def shutdown_callback() do
     Application.fetch_env!(:livebook, :shutdown_callback)
   end
diff --git a/lib/livebook/notebook/cell/code.ex b/lib/livebook/notebook/cell/code.ex
index 2efbd352b..238841158 100644
--- a/lib/livebook/notebook/cell/code.ex
+++ b/lib/livebook/notebook/cell/code.ex
@@ -13,7 +13,7 @@ defmodule Livebook.Notebook.Cell.Code do
 
   @type t :: %__MODULE__{
           id: Cell.id(),
-          source: String.t(),
+          source: String.t() | :__pruned__,
           outputs: list(Cell.indexed_output()),
           disable_formatting: boolean(),
           reevaluate_automatically: boolean()
diff --git a/lib/livebook/notebook/cell/markdown.ex b/lib/livebook/notebook/cell/markdown.ex
index baf25754e..9bac3d765 100644
--- a/lib/livebook/notebook/cell/markdown.ex
+++ b/lib/livebook/notebook/cell/markdown.ex
@@ -13,7 +13,7 @@ defmodule Livebook.Notebook.Cell.Markdown do
 
   @type t :: %__MODULE__{
           id: Cell.id(),
-          source: String.t()
+          source: String.t() | :__pruned__
         }
 
   @doc """
diff --git a/lib/livebook/notebook/cell/smart.ex b/lib/livebook/notebook/cell/smart.ex
index 87d398b1b..b5156e2be 100644
--- a/lib/livebook/notebook/cell/smart.ex
+++ b/lib/livebook/notebook/cell/smart.ex
@@ -10,11 +10,11 @@ defmodule Livebook.Notebook.Cell.Smart do
 
   @type t :: %__MODULE__{
           id: Cell.id(),
-          source: String.t(),
+          source: String.t() | :__pruned__,
           chunks: Livebook.Runtime.chunks() | nil,
           outputs: list(Cell.indexed_output()),
-          kind: String.t(),
-          attrs: attrs(),
+          kind: String.t() | nil,
+          attrs: attrs() | :__pruned__,
           js_view: Livebook.Runtime.js_view() | nil,
           editor: Livebook.Runtime.editor() | nil
         }
diff --git a/lib/livebook/settings/env_var.ex b/lib/livebook/settings/env_var.ex
index 9f6c8ee3d..321995c7f 100644
--- a/lib/livebook/settings/env_var.ex
+++ b/lib/livebook/settings/env_var.ex
@@ -4,8 +4,8 @@ defmodule Livebook.Settings.EnvVar do
   import Ecto.Changeset
 
   @type t :: %__MODULE__{
-          name: String.t(),
-          value: String.t()
+          name: String.t() | nil,
+          value: String.t() | nil
         }
 
   @primary_key {:name, :string, autogenerate: false}
diff --git a/mix.exs b/mix.exs
index d50068175..d46b0f4b2 100644
--- a/mix.exs
+++ b/mix.exs
@@ -153,6 +153,8 @@ defmodule Livebook.MixProject do
     release
   end
 
+  @compile {:no_warn_undefined, Standalone}
+
   defp standalone_erlang_elixir(release) do
     Code.require_file("rel/app/standalone.exs")
 
diff --git a/test/support/test_modules/bad_inspect.ex b/test/support/test_modules/bad_inspect.ex
index df89cd0e9..ddba8567b 100644
--- a/test/support/test_modules/bad_inspect.ex
+++ b/test/support/test_modules/bad_inspect.ex
@@ -2,6 +2,8 @@ defmodule Livebook.TestModules.BadInspect do
   defstruct []
 
   defimpl Inspect do
+    @dialyzer {:nowarn_function, inspect: 2}
+
     def inspect(%Livebook.TestModules.BadInspect{}, _opts) do
       :bad_return
     end