Add simple shell lexer (#1380)

README.md

@@ -94,22 +94,22 @@ You can ExDoc via the command line as follows:
 
 1. Install ExDoc as an escript:
 
-    ```bash
-    $ mix escript.install hex ex_doc
-    ```
+   ```bash
+   $ mix escript.install hex ex_doc
+   ```
 
 2. Then you are ready to use it in your projects. First, move into your project directory and make sure it is already compiled:
 
-    ```bash
-    $ cd PATH_TO_YOUR_PROJECT
-    $ mix compile
-    ```
+   ```bash
+   $ cd PATH_TO_YOUR_PROJECT
+   $ mix compile
+   ```
 
-3. Next invoke the ex_doc executable from your project:
+3. Next invoke the `ex_doc` executable from your project:
 
-    ```bash
-    $ ex_doc "PROJECT_NAME" "PROJECT_VERSION" path/to/project/ebin -m "PROJECT_MODULE" -u "https://github.com/GITHUB_USER/GITHUB_REPO" -l path/to/logo.png
-    ```
+   ```bash
+   $ ex_doc "PROJECT_NAME" "PROJECT_VERSION" path/to/project/ebin -m "PROJECT_MODULE" -u "https://github.com/GITHUB_USER/GITHUB_REPO" -l path/to/logo.png
+   ```
 
 For example, here are some acceptable values:
 

lib/ex_doc/application.ex

@@ -3,6 +3,12 @@ defmodule ExDoc.Application do
   use Application
 
   def start(_type, _args) do
+    Makeup.Registry.register_lexer(ExDoc.ShellLexer,
+      options: [],
+      names: ["shell", "sh", "bash", "zsh"],
+      extensions: []
+    )
+
     Enum.each([:eex, :ex_unit, :iex, :logger, :mix], &Application.load/1)
     Supervisor.start_link([ExDoc.Refs], strategy: :one_for_one)
   end

lib/ex_doc/shell_lexer.ex

@@ -0,0 +1,43 @@
+defmodule ExDoc.ShellLexer do
+  # Makeup lexer for sh, bash, etc commands.
+  # The only thing it does is making the `$ ` prompt not selectable.
+  @moduledoc false
+
+  @behaviour Makeup.Lexer
+
+  @impl true
+  def lex(text, _opts) do
+    text
+    |> String.split("\n")
+    |> Enum.flat_map(fn
+      "$ " <> rest ->
+        [
+          {:generic_prompt, %{selectable: false}, "$ "},
+          {:text, %{}, rest <> "\n"}
+        ]
+
+      text ->
+        [{:text, %{}, text <> "\n"}]
+    end)
+  end
+
+  @impl true
+  def match_groups(_arg0, _arg1) do
+    raise "not implemented yet"
+  end
+
+  @impl true
+  def postprocess(_arg0, _arg1) do
+    raise "not implemented yet"
+  end
+
+  @impl true
+  def root(_arg0) do
+    raise "not implemented yet"
+  end
+
+  @impl true
+  def root_element(_arg0) do
+    raise "not implemented yet"
+  end
+end