From 48da3fe58adbf350c95f8b7d0077d56e3c916d95 Mon Sep 17 00:00:00 2001
From: Milton Mazzarri <milmazz@gmail.com>
Date: Sat, 23 Jun 2018 02:31:48 -0500
Subject: [PATCH] Autolink Kernel and Kernel functions and special forms with
 shorthands

With this change, now we can create the following links:

* [`for`](`for/1`)
* [`is_boolean`](`is_boolean/1`)

Refs: #679
---
 lib/ex_doc/formatter/html/autolink.ex        | 11 ++++++++++-
 test/ex_doc/formatter/html/autolink_test.exs | 12 ++++++++++++
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/lib/ex_doc/formatter/html/autolink.ex b/lib/ex_doc/formatter/html/autolink.ex
index b27a4bac9..3a9b8c84e 100644
--- a/lib/ex_doc/formatter/html/autolink.ex
+++ b/lib/ex_doc/formatter/html/autolink.ex
@@ -419,7 +419,7 @@ defmodule ExDoc.Formatter.HTML.Autolink do
   end
 
   module_re = Regex.source(~r{(([A-Z][A-Za-z_\d]+)\.)+})
-  fun_re = Regex.source(~r{([ct]:)?(#{module_re}(([a-z_]+[A-Za-z_\d]*[\\?\\!]?)|[\{\}=&\\|\\.<>~*^@\\+\\%\\!-\/]+)/\d+)})
+  fun_re = Regex.source(~r{([ct]:)?((#{module_re})?(([a-z_]+[A-Za-z_\d]*[\\?\\!]?)|[\{\}=&\\|\\.<>~*^@\\+\\%\\!-\/]+)/\d+)})
   @custom_re ~r{\[(.*?)\]\(`(#{fun_re})`\)}
   @normal_re ~r{(?<!\[)`\s*(#{fun_re})\s*`(?!\])}
 
@@ -439,10 +439,19 @@ defmodule ExDoc.Formatter.HTML.Autolink do
     {prefix, module, function, arity} = split_function(match)
     text = text || "`#{module}.#{function}/#{arity}`"
 
+    aliases = []
+    elixir_docs = get_elixir_docs(aliases, lib_dirs)
+
     cond do
       match in project_funs ->
         "[#{text}](#{module}#{extension}##{prefix}#{enc_h function}/#{arity})"
 
+      match in @kernel_function_strings ->
+        "[#{text}](#{elixir_docs}Kernel#{extension}##{prefix}#{enc_h function}/#{arity})"
+
+      match in @special_form_strings ->
+        "[#{text}](#{elixir_docs}Kernel.SpecialForms#{extension}##{prefix}#{enc_h function}/#{arity})"
+
       doc = lib_dirs_to_doc("Elixir." <> module, lib_dirs) ->
         "[#{text}](#{doc}#{module}.html##{prefix}#{enc_h function}/#{arity})"
 
diff --git a/test/ex_doc/formatter/html/autolink_test.exs b/test/ex_doc/formatter/html/autolink_test.exs
index 6c902f32f..dde6eb384 100644
--- a/test/ex_doc/formatter/html/autolink_test.exs
+++ b/test/ex_doc/formatter/html/autolink_test.exs
@@ -147,6 +147,18 @@ defmodule ExDoc.Formatter.HTML.AutolinkTest do
 
     assert Autolink.elixir_functions("[`foo`](`Foo.//2`)", ["Foo.//2"]) ==
            "[`foo`](Foo.html#//2)"
+
+    assert Autolink.elixir_functions("[`for`](`Kernel.SpecialForms.for/1`)", []) ==
+      "[`for`](#{@elixir_docs}elixir/Kernel.SpecialForms.html#for/1)"
+
+    assert Autolink.elixir_functions("[`for`](`for/1`)", []) ==
+      "[`for`](#{@elixir_docs}elixir/Kernel.SpecialForms.html#for/1)"
+
+    assert Autolink.elixir_functions("[`is_boolean`](`Kernel.is_boolean/1`)", []) ==
+      "[`is_boolean`](#{@elixir_docs}elixir/Kernel.html#is_boolean/1)"
+
+    assert Autolink.elixir_functions("[`is_boolean`](`is_boolean/1`)", []) ==
+      "[`is_boolean`](#{@elixir_docs}elixir/Kernel.html#is_boolean/1)"
   end
 
   test "autolink functions to types in the project" do