Consider distance to previous comment in comment metadata, closes #14375

Author: josevalim

lib/elixir/lib/code.ex

@@ -1376,7 +1376,7 @@ defmodule Code do
     comment = %{
       line: line,
       column: column,
-      previous_eol_count: previous_eol_count(tokens),
+      previous_eol_count: min(previous_eol_count(tokens), last_comment_distance(comments, line)),
       next_eol_count: next_eol_count(rest, 0),
       text: List.to_string(comment)
     }
@@ -1390,6 +1390,9 @@ defmodule Code do
   defp next_eol_count([?\r, ?\n | rest], count), do: next_eol_count(rest, count + 1)
   defp next_eol_count(_, count), do: count
 
+  defp last_comment_distance([%{line: last_line} | _], line), do: line - last_line
+  defp last_comment_distance([], _line), do: :infinity
+
   defp previous_eol_count([{token, {_, _, count}} | _])
        when token in [:eol, :",", :";"] and count > 0 do
     count

lib/elixir/test/elixir/code_test.exs

@@ -443,6 +443,77 @@ defmodule CodeTest do
     assert meta[:end_column] == 3
   end
 
+  test "string_to_quoted with comments" do
+    assert Code.string_to_quoted_with_comments("""
+           # top
+           [
+             # before
+
+             # right-before
+             expr, # middle
+             # right-after
+
+             # after
+           ]
+           # bottom
+           """) ==
+             {
+               :ok,
+               [{:expr, [line: 6], nil}],
+               [
+                 %{
+                   column: 1,
+                   line: 1,
+                   next_eol_count: 1,
+                   previous_eol_count: 1,
+                   text: "# top"
+                 },
+                 %{
+                   column: 3,
+                   line: 3,
+                   next_eol_count: 2,
+                   previous_eol_count: 1,
+                   text: "# before"
+                 },
+                 %{
+                   column: 3,
+                   line: 5,
+                   next_eol_count: 1,
+                   previous_eol_count: 2,
+                   text: "# right-before"
+                 },
+                 %{
+                   column: 9,
+                   line: 6,
+                   next_eol_count: 1,
+                   previous_eol_count: 0,
+                   text: "# middle"
+                 },
+                 %{
+                   column: 3,
+                   line: 7,
+                   next_eol_count: 2,
+                   previous_eol_count: 1,
+                   text: "# right-after"
+                 },
+                 %{
+                   column: 3,
+                   line: 9,
+                   next_eol_count: 1,
+                   previous_eol_count: 2,
+                   text: "# after"
+                 },
+                 %{
+                   column: 1,
+                   line: 11,
+                   next_eol_count: 1,
+                   previous_eol_count: 1,
+                   text: "# bottom"
+                 }
+               ]
+             }
+  end
+
   @tag :requires_source
   test "compile source" do
     assert __MODULE__.__info__(:compile)[:source] == String.to_charlist(__ENV__.file)