Support for umbrella projects via CLI

README.md

@@ -114,6 +114,14 @@ You can use ExDoc via the command line.
    GITHUB_REPO     => ecto
    ```
 
+It is also possible to specify multiple `ebin` directories in the case of _umbrella_ projects:
+
+   ```bash
+   $ ex_doc "PROJECT_NAME" "PROJECT_VERSION" _build/dev/lib/app1/ebin _build/dev/lib/app2/ebin -m "PROJECT_MODULE" -u "https://github.com/GITHUB_USER/GITHUB_REPO" -l path/to/logo.png
+   ```
+
+If multiple `ebin` directories are specified, modules are grouped by application by default. It is possible to override this behaviour by providing a custom `groups_per_modules` option.
+
 You can specify a config file via the `--config` option, both Elixir and Erlang formats are supported. Invoke `ex_doc` without arguments to learn more.
 
 <!-- tabs-close -->

lib/ex_doc/cli.ex

@@ -69,9 +69,9 @@ defmodule ExDoc.CLI do
   end
 
   defp generate(args, opts, generator) do
-    [project, version, source_beam] = parse_args(args)
+    [project, version | source_beams] = parse_args(args)
 
-    Code.prepend_path(source_beam)
+    Code.prepend_paths(source_beams)
 
     for path <- Keyword.get_values(opts, :paths),
         path <- Path.wildcard(path) do
@@ -80,8 +80,8 @@ defmodule ExDoc.CLI do
 
     opts =
       opts
-      |> Keyword.put(:source_beam, source_beam)
-      |> Keyword.put(:apps, [app(source_beam)])
+      |> Keyword.put(:source_beam, source_beams)
+      |> Keyword.put(:apps, Enum.map(source_beams, &app/1))
       |> merge_config()
       |> normalize_formatters()
 
@@ -166,13 +166,7 @@ defmodule ExDoc.CLI do
     end
   end
 
-  defp parse_args([_project, _version, _source_beam] = args), do: args
-
-  defp parse_args([_, _, _ | _]) do
-    IO.puts("Too many arguments.\n")
-    print_usage()
-    exit({:shutdown, 1})
-  end
+  defp parse_args([_project, _version | _source_beams] = args), do: args
 
   defp parse_args(_) do
     IO.puts("Too few arguments.\n")

lib/ex_doc/config.ex

@@ -115,7 +115,10 @@ defmodule ExDoc.Config do
 
     {groups_for_docs, options} = Keyword.pop(options, :groups_for_docs, [])
     {groups_for_extras, options} = Keyword.pop(options, :groups_for_extras, [])
-    {groups_for_modules, options} = Keyword.pop(options, :groups_for_modules, [])
+    apps = Keyword.get(options, :apps, [])
+
+    {groups_for_modules, options} =
+      Keyword.pop(options, :groups_for_modules, default_groups_for_modules(apps))
 
     {skip_undefined_reference_warnings_on, options} =
       Keyword.pop(
@@ -278,4 +281,15 @@ defmodule ExDoc.Config do
   defp append_slash(url) do
     if :binary.last(url) == ?/, do: url, else: url <> "/"
   end
+
+  defp default_groups_for_modules([_app]) do
+    []
+  end
+
+  defp default_groups_for_modules(apps) do
+    Enum.map(apps, fn app ->
+      Application.load(app)
+      {app, Application.spec(app, :modules)}
+    end)
+  end
 end

test/ex_doc/cli_test.exs

@@ -3,6 +3,7 @@ defmodule ExDoc.CLITest do
   import ExUnit.CaptureIO
 
   @ebin "_build/test/lib/ex_doc/ebin"
+  @ebin2 "_build/test/lib/makeup/ebin"
 
   defp run(args) do
     with_io(fn -> ExDoc.CLI.main(args, &{&1, &2, &3}) end)
@@ -17,7 +18,7 @@ defmodule ExDoc.CLITest do
                 formatter: "html",
                 formatters: ["html", "epub"],
                 apps: [:ex_doc],
-                source_beam: @ebin
+                source_beam: [@ebin]
               ]}
 
     assert epub ==
@@ -26,7 +27,7 @@ defmodule ExDoc.CLITest do
                 formatter: "epub",
                 formatters: ["html", "epub"],
                 apps: [:ex_doc],
-                source_beam: @ebin
+                source_beam: [@ebin]
               ]}
   end
 
@@ -39,7 +40,7 @@ defmodule ExDoc.CLITest do
                 formatter: "epub",
                 formatters: ["epub", "html"],
                 apps: [:ex_doc],
-                source_beam: @ebin
+                source_beam: [@ebin]
               ]}
 
     assert html ==
@@ -48,7 +49,7 @@ defmodule ExDoc.CLITest do
                 formatter: "html",
                 formatters: ["epub", "html"],
                 apps: [:ex_doc],
-                source_beam: @ebin
+                source_beam: [@ebin]
               ]}
   end
 
@@ -60,14 +61,18 @@ defmodule ExDoc.CLITest do
     assert io == "ExDoc v#{ExDoc.version()}\n"
   end
 
-  test "too many arguments" do
-    assert catch_exit(run(["ExDoc", "1.2.3", "/", "kaboom"])) == {:shutdown, 1}
-  end
-
   test "too few arguments" do
     assert catch_exit(run(["ExDoc"])) == {:shutdown, 1}
   end
 
+  test "multiple apps" do
+    {[{"ExDoc", "1.2.3", html}, {"ExDoc", "1.2.3", epub}], _io} =
+      run(["ExDoc", "1.2.3", @ebin, @ebin2])
+
+    assert [:ex_doc, :makeup] = Enum.sort(Keyword.get(html, :apps))
+    assert [:ex_doc, :makeup] = Enum.sort(Keyword.get(epub, :apps))
+  end
+
   test "arguments that are not aliased" do
     File.write!("not_aliased.exs", ~s([key: "val"]))
 
@@ -98,7 +103,7 @@ defmodule ExDoc.CLITest do
              logo: "logo.png",
              main: "Main",
              output: "html",
-             source_beam: "#{@ebin}",
+             source_beam: ["#{@ebin}"],
              source_ref: "abcdefg",
              source_url: "http://example.com/username/project"
            ]
@@ -127,7 +132,7 @@ defmodule ExDoc.CLITest do
                extras: ["README.md"],
                formatter: "html",
                formatters: ["html"],
-               source_beam: @ebin
+               source_beam: [@ebin]
              ]
     after
       File.rm!("test.exs")
@@ -155,7 +160,7 @@ defmodule ExDoc.CLITest do
                formatter: "html",
                formatters: ["html"],
                logo: "opts_logo.png",
-               source_beam: @ebin
+               source_beam: [@ebin]
              ]
     after
       File.rm!("test.exs")
@@ -192,7 +197,7 @@ defmodule ExDoc.CLITest do
                extras: ["README.md"],
                formatter: "html",
                formatters: ["html"],
-               source_beam: @ebin
+               source_beam: [@ebin]
              ]
     after
       File.rm!("test.config")

test/ex_doc/config_test.exs

@@ -113,5 +113,43 @@ defmodule ExDoc.ConfigTest do
       config = build(source_url_pattern: "a%{line}b%{path}c")
       assert config.source_url_pattern.("foo.ex", 123) == "a123bfoo.exc"
     end
+
+    test "groups_for_modules" do
+      # Using real applications, since we load them to extract the corresponding list of modules
+      stdlib = :stdlib
+      kernel = :kernel
+      custom_group = :custom_group
+
+      groups_for_modules = fn config, key ->
+        List.keyfind(config.groups_for_modules, to_string(key), 0)
+      end
+
+      # Single app, no custom grouping
+      config = build(apps: [stdlib])
+      assert groups_for_modules.(config, stdlib) == nil
+      assert groups_for_modules.(config, custom_group) == nil
+
+      # Single app, custom grouping
+      config = build(apps: [stdlib], groups_for_modules: [{"custom_group", ["module_1"]}])
+      assert groups_for_modules.(config, stdlib) == nil
+      assert groups_for_modules.(config, custom_group) == {"custom_group", ["module_1"]}
+
+      # Multiple apps, no custom grouping
+      config = build(apps: [stdlib, kernel])
+      stdlib_groups = groups_for_modules.(config, stdlib)
+      kernel_groups = groups_for_modules.(config, kernel)
+      assert match?({"stdlib", _}, stdlib_groups)
+      assert match?({"kernel", _}, kernel_groups)
+      {"stdlib", stdlib_modules} = stdlib_groups
+      {"kernel", kernel_modules} = kernel_groups
+      assert Enum.member?(stdlib_modules, :gen_server)
+      assert Enum.member?(kernel_modules, :file)
+
+      # Multiple apps, custom grouping
+      config = build(apps: [stdlib, kernel], groups_for_modules: [{"custom_group", ["module_1"]}])
+      assert groups_for_modules.(config, stdlib) == nil
+      assert groups_for_modules.(config, kernel) == nil
+      assert groups_for_modules.(config, custom_group) == {"custom_group", ["module_1"]}
+    end
   end
 end