improvement: show warning when adding dependencies by default

lib/deps.ex

@@ -4,13 +4,21 @@ defmodule Igniter.Deps do
   alias Igniter.Code.Common
   alias Sourceror.Zipper
 
-  def add_dependency(igniter, name, version, yes? \\ false) do
+  @doc """
+  Adds a dependency to the mix.exs file.
+
+  # Options
+
+  - `:yes?` - Automatically answer yes to any prompts.
+  - `:error?` - Returns an error instead of a notice on failure.
+  """
+  def add_dependency(igniter, name, version, opts \\ []) do
     if name in List.wrap(igniter.assigns[:manually_installed]) do
       igniter
     else
       case get_dependency_declaration(igniter, name) do
         nil ->
-          do_add_dependency(igniter, name, version)
+          do_add_dependency(igniter, name, version, opts)
 
         current ->
           desired = "`{#{inspect(name)}, #{inspect(version)}}`"
@@ -19,7 +27,7 @@ defmodule Igniter.Deps do
           if desired == current do
             igniter
           else
-            if yes? ||
+            if opts[:yes?] ||
                  Mix.shell().yes?("""
                  Dependency #{name} is already in mix.exs. Should we replace it?
 
@@ -28,7 +36,7 @@ defmodule Igniter.Deps do
                  """) do
               igniter
               |> remove_dependency(name)
-              |> do_add_dependency(name, version)
+              |> do_add_dependency(name, version, opts)
             else
               igniter
             end
@@ -97,7 +105,7 @@ defmodule Igniter.Deps do
     end)
   end
 
-  defp do_add_dependency(igniter, name, version) do
+  defp do_add_dependency(igniter, name, version, opts) do
     igniter
     |> Igniter.update_elixir_file("mix.exs", fn zipper ->
       with {:ok, zipper} <- Igniter.Code.Module.move_to_module_using(zipper, Mix.Project),
@@ -111,7 +119,26 @@ defmodule Igniter.Deps do
         Igniter.Code.List.prepend_to_list(zipper, quoted)
       else
         _ ->
-          {:error, "Failed to add dependency #{inspect({inspect(name), inspect(version)})}"}
+          if opts[:error?] do
+            {:error,
+             """
+             Could not add dependency #{inspect({inspect(name), inspect(version)})}
+
+             `mix.exs` file does not contain a simple list of dependencies in a `deps/0` function.
+             Please add it manually and run the installer again.
+             """}
+          else
+            {:warning,
+             [
+               """
+               Could not add dependency #{inspect({inspect(name), inspect(version)})}
+
+               `mix.exs` file does not contain a simple list of dependencies in a `deps/0` function.
+
+               Please add it manually.
+               """
+             ]}
+          end
       end
     end)
   end

lib/igniter.ex

@@ -80,14 +80,15 @@ defmodule Igniter do
   end
 
   @doc "Adds an issue to the issues list. Any issues will prevent writing and be displayed to the user."
-  @spec add_issue(t, term) :: t()
+  @spec add_issue(t, term | list(term)) :: t()
   def add_issue(igniter, issue) do
-    %{igniter | issues: [issue | igniter.issues]}
+    %{igniter | issues: List.wrap(issue) ++ igniter.issues}
   end
 
   @doc "Adds a warning to the warnings list. Warnings will not prevent writing, but will be displayed to the user."
+  @spec add_warning(t, term | list(term)) :: t()
   def add_warning(igniter, warning) do
-    %{igniter | issues: [warning | igniter.warnings]}
+    %{igniter | warnings: List.wrap(warning) ++ igniter.warnings}
   end
 
   @doc "Adds a task to the tasks list. Tasks will be run after all changes have been commited"
@@ -134,13 +135,10 @@ defmodule Igniter do
   @spec update_elixir_file(t(), Path.t(), zipper_updater()) :: Igniter.t()
   def update_elixir_file(igniter, path, func) do
     if Rewrite.has_source?(igniter.rewrite, path) do
-      %{
+      source = Rewrite.source!(igniter.rewrite, path)
-        igniter
+
-        | rewrite:
+      igniter
-            Rewrite.update!(igniter.rewrite, path, fn source ->
+      |> apply_func_with_zipper(source, func)
-              apply_func_with_zipper(source, func)
-            end)
-      }
       |> format(path)
     else
       if File.exists?(path) do
@@ -148,11 +146,7 @@ defmodule Igniter do
 
         %{igniter | rewrite: Rewrite.put!(igniter.rewrite, source)}
         |> format(path)
-        |> Map.update!(:rewrite, fn rewrite ->
+        |> apply_func_with_zipper(source, func)
-          Rewrite.update!(rewrite, path, fn source ->
-            apply_func_with_zipper(source, func)
-          end)
-        end)
       else
         add_issue(igniter, "Required #{path} but it did not exist")
       end
@@ -368,6 +362,20 @@ defmodule Igniter do
                   :dry_run_with_changes
               end
 
+            if igniter.warnings != [] do
+              Mix.shell().info("\n#{title} - #{IO.ANSI.yellow()}Notices:#{IO.ANSI.reset()}\n")
+
+              igniter.warnings
+              |> Enum.map_join("\n --- \n", fn error ->
+                if is_binary(error) do
+                  "* #{IO.ANSI.yellow()}#{error}#{IO.ANSI.reset()}"
+                else
+                  "* #{IO.ANSI.yellow()}#{Exception.format(:error, error)}#{IO.ANSI.reset()}"
+                end
+              end)
+              |> Mix.shell().info()
+            end
+
             if igniter.tasks != [] do
               message =
                 if result_of_dry_run == :dry_run_with_no_changes do
@@ -455,7 +463,7 @@ defmodule Igniter do
           "* #{Exception.format(:error, error)}"
         end
       end)
-      |> Mix.shell().info()
+      |> Mix.shell().error()
     end)
   end
 
@@ -655,29 +663,44 @@ defmodule Igniter do
     opts
   end
 
-  defp apply_func_with_zipper(source, func) do
+  defp apply_func_with_zipper(igniter, source, func) do
     quoted = Rewrite.Source.get(source, :quoted)
     zipper = Sourceror.Zipper.zip(quoted)
 
     case func.(zipper) do
       {:ok, %Sourceror.Zipper{} = zipper} ->
-        Rewrite.Source.update(
+        Rewrite.update!(
-          source,
+          igniter.rewrite,
-          :configure,
+          Rewrite.Source.update(
-          :quoted,
+            source,
-          Sourceror.Zipper.root(zipper)
+            :configure,
+            :quoted,
+            Sourceror.Zipper.root(zipper)
+          )
         )
+        |> then(&Map.put(igniter, :rewrite, &1))
 
       %Sourceror.Zipper{} = zipper ->
-        Rewrite.Source.update(
+        Rewrite.update!(
-          source,
+          igniter.rewrite,
-          :configure,
+          Rewrite.Source.update(
-          :quoted,
+            source,
-          Sourceror.Zipper.root(zipper)
+            :configure,
+            :quoted,
+            Sourceror.Zipper.root(zipper)
+          )
         )
+        |> then(&Map.put(igniter, :rewrite, &1))
 
       {:error, error} ->
-        Rewrite.Source.add_issues(source, List.wrap(error))
+        Rewrite.update!(
+          igniter.rewrite,
+          Rewrite.Source.add_issues(source, List.wrap(error))
+        )
+        |> then(&Map.put(igniter, :rewrite, &1))
+
+      {:warning, warning} ->
+        Igniter.add_warning(igniter, warning)
     end
   end
 

lib/install.ex

@@ -43,8 +43,10 @@ defmodule Igniter.Install do
 
               {igniter, [install | install_list]}
             else
-              {Igniter.Deps.add_dependency(igniter, install, requirement, "--yes" in argv),
+              {Igniter.Deps.add_dependency(igniter, install, requirement,
-               [install | install_list]}
+                 error?: true,
+                 yes?: "--yes" in argv
+               ), [install | install_list]}
             end
 
           :error ->