Add "mix " to Mix tasks

lib/ex_doc/formatter/html/templates.ex

@@ -49,7 +49,7 @@ defmodule ExDoc.Formatter.HTML.Templates do
   Returns the HTML formatted title for the module page.
   """
   def module_title(%{type: :task, title: title}),
-    do: "mix " <> title
+    do: title
 
   def module_title(%{type: :module, title: title}),
     do: title

lib/ex_doc/retriever.ex

@@ -547,7 +547,7 @@ defmodule ExDoc.Retriever do
   end
 
   defp module_title_and_id(%{name: module, type: :task}) do
-    {task_name(module), module_id(module)}
+    {"mix " <> task_name(module), module_id(module)}
   end
 
   defp module_title_and_id(%{name: module}) do

test/ex_doc/formatter/html_test.exs

@@ -191,7 +191,7 @@ defmodule ExDoc.Formatter.HTMLTest do
     assert content =~ ~r{"id":"CustomBehaviourTwo","title":"CustomBehaviourTwo"}ms
     assert content =~ ~r{"id":"RandomError","title":"RandomError"}ms
     assert content =~ ~r{"id":"CustomProtocol","title":"CustomProtocol"}ms
-    assert content =~ ~r{"id":"Mix\.Tasks\.TaskWithDocs","title":"task_with_docs"}ms
+    assert content =~ ~r{"id":"Mix\.Tasks\.TaskWithDocs","title":"mix task_with_docs"}ms
   end
 
   test "generates the api reference file" do
@@ -201,7 +201,7 @@ defmodule ExDoc.Formatter.HTMLTest do
     assert content =~ ~r{<a href="CompiledWithDocs.html">CompiledWithDocs</a>}
     assert content =~ ~r{<p>moduledoc</p>}
     assert content =~ ~r{<a href="CompiledWithDocs.Nested.html">CompiledWithDocs.Nested</a>}
-    assert content =~ ~r{<a href="Mix.Tasks.TaskWithDocs.html">task_with_docs</a>}
+    assert content =~ ~r{<a href="Mix.Tasks.TaskWithDocs.html">mix task_with_docs</a>}
   end
 
   test "groups modules by nesting" do

test/ex_doc/retriever_test.exs

@@ -237,7 +237,7 @@ defmodule ExDoc.RetrieverTest do
       [module_node] = docs_from_files(["Mix.Tasks.TaskWithDocs"])
       assert module_node.type == :task
       assert module_node.id == "Mix.Tasks.TaskWithDocs"
-      assert module_node.title == "task_with_docs"
+      assert module_node.title == "mix task_with_docs"
     end
   end