Inject help commands and flags into the CLI spec (#22)

* bump versions

* wip

* feat: help flags

* fix

Author: zoedsoupe

examples/escript/example.ex

@@ -13,9 +13,9 @@ defmodule Escript.Example do
   from the `main/1` escript funciton, as can seen below.
   """
 
-  use Nexus.CLI
+  use Nexus.CLI, otp_app: :nexus_cli
 
-  defcommand :foo do
+  defcommand :echo do
     description "Command that receives a string as argument and prints it."
 
     value :string, required: true
@@ -24,7 +24,7 @@ defmodule Escript.Example do
   defcommand :fizzbuzz do
     description "Fizz bUZZ"
 
-    value {:enum, ~w(fizz buzz)a}, required: true
+    value :integer, required: true
   end
 
   defcommand :foo_bar do
@@ -47,27 +47,28 @@ defmodule Escript.Example do
   def version, do: "0.1.0"
 
   @impl true
-  def handle_input(:foo, input) do
-    IO.puts(inspect(input))
+  def handle_input(:echo, %{value: value}) do
+    IO.puts(value)
   end
 
-  def handle_input(:fizzbuzz, %{value: :fizz}) do
-    IO.puts("buzz")
-  end
-
-  def handle_input(:fizzbuzz, %{value: :buzz}) do
-    IO.puts("fizz")
+  def handle_input(:fizzbuzz, %{value: value}) when is_integer(value) do
+    cond do
+      rem(value, 3) == 0 and rem(value, 5) == 0 -> IO.puts("fizzbuzz")
+      rem(value, 3) == 0 -> IO.puts("fizz")
+      rem(value, 5) == 0 -> IO.puts("buzz")
+      true -> IO.puts value
+    end
   end
 
-  def handle_input(:foo_bar, %{value: _, subcommand: :foo}) do
-    # do something wth "foo" value
+  def handle_input([:foo_bar, :foo], %{value: _}) do
+    IO.puts("Issued foo")
     :ok
   end
 
-  def handle_input(:foo_bar, %{value: _, subcommand: :bar}) do
-    # do something wth "bar" value
+  def handle_input([:foo_bar, :bar], %{value: _}) do
+    IO.puts("Issued bar")
     :ok
   end
 
-  # defdelegate main(args), to: __MODULE__, as: :run
+  defdelegate main(args), to: __MODULE__, as: :execute
 end

examples/file_management.ex

@@ -5,6 +5,32 @@ defmodule MyCLI do
 
   use Nexus.CLI, otp_app: :nexus_cli
 
+  defcommand :version do
+    description "Shows the version of the CLI"
+  end
+
+  defcommand :folder do
+    description "Performs folder operations like merging"
+
+    subcommand :merge do
+      description "Merges two or more directories"
+
+      value {:list, :string}, required: true, as: :targets
+
+      flag :level do
+        description "The level of the folder that will be merged"
+        value :integer, required: false
+        short :l
+      end
+
+      flag :recursive do
+        description "IF the merge should operate recursively"
+        value :boolean, required: false, default: false
+        short :rc
+      end
+    end
+  end
+
   defcommand :file do
     description "Performs file operations such as copy, move, and delete."
 
@@ -69,6 +95,28 @@ defmodule MyCLI do
   end
 
   @impl Nexus.CLI
+  def handle_input(:version, _) do
+    # `version/0` comes from Nexus.CLI or the callback this module defined
+    vsn = version()
+    IO.puts(vsn)
+  end
+
+  def handle_input([:folder, :merge], %{args: args, flags: flags}) do
+    if flags.recursive do
+      IO.puts("Recursive merging enabled")
+    end
+
+    if level = flags.level do
+      IO.puts("Set level of merging to #{level}")
+    end
+
+    Enum.each(args.targets, fn target ->
+      IO.puts("Merged #{target}")
+    end)
+
+    :ok
+  end
+
   def handle_input([:file, :copy], %{args: args, flags: flags}) do
     if flags.verbose do
       IO.puts("Copying from #{args.source} to #{args.dest}")
@@ -117,11 +165,4 @@ defmodule MyCLI do
 
     :ok
   end
-
-  def handle_input(command, input) do
-    IO.puts("Unknown command or invalid parameters")
-    IO.inspect(command, label: "CMD")
-    IO.inspect(input, label: "INPUT")
-    :error
-  end
 end

examples/mix/tasks/example.ex

@@ -1,12 +1,10 @@
 defmodule Mix.Tasks.Example do
   @moduledoc """
   This is a Mix Task example using Nexus.
-  Basically, you can `use` both `Mix.Task` and `Nexus`
+  Basically, you can `use` both `Mix.Task` and `Nexus.CLI`
   modules, define your commands as usual with `defcommand/2`
   and implement others callbacks.
 
-  Then you need to call `Nexus.parse/0`, that will inject
-  both `parse/1` and `run/1` functions into your module.
   In a `Mix.Task` module, the `run/1` function will supply
   the behaviour, so you don't need to define it yourself.
 
@@ -16,9 +14,12 @@ defmodule Mix.Tasks.Example do
   """
 
   use Mix.Task
-  use Nexus
+  use Nexus.CLI, otp_app: :nexus_cli
 
-  defcommand :foo, type: :string, required: false, default: "bar", doc: "This is a foo command"
+  defcommand :foo do
+    description "This is a foo command"
+    value :string, required: false, default: "bar"
+  end
 
   @impl Nexus.CLI
   def version, do: "0.1.0"
@@ -31,6 +32,6 @@ defmodule Mix.Tasks.Example do
     IO.puts("Running :foo command...")
   end
 
-  Nexus.help()
-  Nexus.parse()
+  @impl Mix.Task
+  defdelegate run(argv), to: __MODULE__, as: :execute
 end

flake.nix

@@ -29,7 +29,7 @@
           mkShell {
             name = "nexus";
             packages = with pkgs;
-              [beam.elixir_1_17]
+              [beam.elixir_1_17 erlang_27]
               ++ lib.optional stdenv.isLinux [inotify-tools]
               ++ lib.optional stdenv.isDarwin [
                 darwin.apple_sdk.frameworks.CoreServices