From baead4ea4b84ab1190b87a2dc73cdc4afaa6ebc6 Mon Sep 17 00:00:00 2001
From: Maksim Pechnikov <parallel588@gmail.com>
Date: Fri, 14 Dec 2018 12:41:55 +0300
Subject: [PATCH] fix markdown formatting

---
 lib/pleroma/formatter.ex                           | 14 ++++++++++++++
 lib/pleroma/html.ex                                | 10 ++--------
 lib/pleroma/web/common_api/utils.ex                | 10 ++++++++++
 lib/pleroma/web/twitter_api/views/activity_view.ex |  3 ++-
 mix.exs                                            |  2 +-
 mix.lock                                           |  2 +-
 test/formatter_test.exs                            | 19 +++++++++++++++++++
 7 files changed, 49 insertions(+), 11 deletions(-)

diff --git a/lib/pleroma/formatter.ex b/lib/pleroma/formatter.ex
index 133683794..b6079551c 100644
--- a/lib/pleroma/formatter.ex
+++ b/lib/pleroma/formatter.ex
@@ -5,6 +5,8 @@ defmodule Pleroma.Formatter do
   alias Pleroma.Emoji
 
   @tag_regex ~r/\#\w+/u
+  @mardown_characters_regex ~r/(`|\*|_|{|}|[|]|\(|\)|#|\+|-|\.|!)/
+
   def parse_tags(text, data \\ %{}) do
     Regex.scan(@tag_regex, text)
     |> Enum.map(fn ["#" <> tag = full_tag] -> {full_tag, String.downcase(tag)} end)
@@ -76,6 +78,18 @@ defmodule Pleroma.Formatter do
     |> Enum.join("")
   end
 
+  @doc """
+  Escapes a special characters in mention names.
+  """
+  @spec mentions_escape(String.t(), list({String.t(), any()})) :: String.t()
+  def mentions_escape(text, mentions) do
+    mentions
+    |> Enum.reduce(text, fn {name, _}, acc ->
+      escape_name = String.replace(name, @mardown_characters_regex, "\\\\\\1")
+      String.replace(acc, name, escape_name)
+    end)
+  end
+
   @doc "changes scheme:... urls to html links"
   def add_links({subs, text}) do
     links =
diff --git a/lib/pleroma/html.ex b/lib/pleroma/html.ex
index 8a0333461..583f05aeb 100644
--- a/lib/pleroma/html.ex
+++ b/lib/pleroma/html.ex
@@ -17,15 +17,9 @@ defmodule Pleroma.HTML do
     end)
   end
 
-  def filter_tags(html, scrubber) do
-    html |> Scrubber.scrub(scrubber)
-  end
-
+  def filter_tags(html, scrubber), do: Scrubber.scrub(html, scrubber)
   def filter_tags(html), do: filter_tags(html, nil)
-
-  def strip_tags(html) do
-    html |> Scrubber.scrub(Scrubber.StripTags)
-  end
+  def strip_tags(html), do: Scrubber.scrub(html, Scrubber.StripTags)
 end
 
 defmodule Pleroma.HTML.Scrubber.TwitterText do
diff --git a/lib/pleroma/web/common_api/utils.ex b/lib/pleroma/web/common_api/utils.ex
index ce0926b99..142283684 100644
--- a/lib/pleroma/web/common_api/utils.ex
+++ b/lib/pleroma/web/common_api/utils.ex
@@ -112,6 +112,9 @@ defmodule Pleroma.Web.CommonAPI.Utils do
     Enum.join([text | attachment_text], "<br>")
   end
 
+  @doc """
+  Formatting text to plain text.
+  """
   def format_input(text, mentions, tags, "text/plain") do
     text
     |> Formatter.html_escape("text/plain")
@@ -123,6 +126,9 @@ defmodule Pleroma.Web.CommonAPI.Utils do
     |> Formatter.finalize()
   end
 
+  @doc """
+  Formatting text to html.
+  """
   def format_input(text, mentions, _tags, "text/html") do
     text
     |> Formatter.html_escape("text/html")
@@ -132,8 +138,12 @@ defmodule Pleroma.Web.CommonAPI.Utils do
     |> Formatter.finalize()
   end
 
+  @doc """
+  Formatting text to markdown.
+  """
   def format_input(text, mentions, tags, "text/markdown") do
     text
+    |> Formatter.mentions_escape(mentions)
     |> Earmark.as_html!()
     |> Formatter.html_escape("text/html")
     |> String.replace(~r/\r?\n/, "")
diff --git a/lib/pleroma/web/twitter_api/views/activity_view.ex b/lib/pleroma/web/twitter_api/views/activity_view.ex
index e5caed28f..433c3b141 100644
--- a/lib/pleroma/web/twitter_api/views/activity_view.ex
+++ b/lib/pleroma/web/twitter_api/views/activity_view.ex
@@ -239,7 +239,8 @@ defmodule Pleroma.Web.TwitterAPI.ActivityView do
     {summary, content} = render_content(object)
 
     html =
-      HTML.filter_tags(content, User.html_filter_policy(opts[:for]))
+      content
+      |> HTML.filter_tags(User.html_filter_policy(opts[:for]))
       |> Formatter.emojify(object["emoji"])
 
     reply_parent = Activity.get_in_reply_to_activity(activity)
diff --git a/mix.exs b/mix.exs
index 0fb40e07b..a8a171eb9 100644
--- a/mix.exs
+++ b/mix.exs
@@ -67,7 +67,7 @@ defmodule Pleroma.Mixfile do
       {:mogrify, "~> 0.6.1"},
       {:ex_aws, "~> 2.0"},
       {:ex_aws_s3, "~> 2.0"},
-      {:earmark, "~> 1.2"},
+      {:earmark, "~> 1.3"},
       {:ex_machina, "~> 2.2", only: :test},
       {:credo, "~> 0.9.3", only: [:dev, :test]},
       {:mock, "~> 0.3.1", only: :test},
diff --git a/mix.lock b/mix.lock
index d9ae9a83b..6f8ca5bb0 100644
--- a/mix.lock
+++ b/mix.lock
@@ -13,7 +13,7 @@
   "crypt": {:git, "https://github.com/msantos/crypt", "1f2b58927ab57e72910191a7ebaeff984382a1d3", [ref: "1f2b58927ab57e72910191a7ebaeff984382a1d3"]},
   "db_connection": {:hex, :db_connection, "1.1.3", "89b30ca1ef0a3b469b1c779579590688561d586694a3ce8792985d4d7e575a61", [:mix], [{:connection, "~> 1.0.2", [hex: :connection, repo: "hexpm", optional: false]}, {:poolboy, "~> 1.5", [hex: :poolboy, repo: "hexpm", optional: true]}, {:sbroker, "~> 1.0", [hex: :sbroker, repo: "hexpm", optional: true]}], "hexpm"},
   "decimal": {:hex, :decimal, "1.5.0", "b0433a36d0e2430e3d50291b1c65f53c37d56f83665b43d79963684865beab68", [:mix], [], "hexpm"},
-  "earmark": {:hex, :earmark, "1.2.6", "b6da42b3831458d3ecc57314dff3051b080b9b2be88c2e5aa41cd642a5b044ed", [:mix], [], "hexpm"},
+  "earmark": {:hex, :earmark, "1.3.0", "17f0c38eaafb4800f746b457313af4b2442a8c2405b49c645768680f900be603", [:mix], [], "hexpm"},
   "ecto": {:hex, :ecto, "2.2.10", "e7366dc82f48f8dd78fcbf3ab50985ceeb11cb3dc93435147c6e13f2cda0992e", [:mix], [{:db_connection, "~> 1.1", [hex: :db_connection, repo: "hexpm", optional: true]}, {:decimal, "~> 1.2", [hex: :decimal, repo: "hexpm", optional: false]}, {:mariaex, "~> 0.8.0", [hex: :mariaex, repo: "hexpm", optional: true]}, {:poison, "~> 2.2 or ~> 3.0", [hex: :poison, repo: "hexpm", optional: true]}, {:poolboy, "~> 1.5", [hex: :poolboy, repo: "hexpm", optional: false]}, {:postgrex, "~> 0.13.0", [hex: :postgrex, repo: "hexpm", optional: true]}, {:sbroker, "~> 1.0", [hex: :sbroker, repo: "hexpm", optional: true]}], "hexpm"},
   "eternal": {:hex, :eternal, "1.2.0", "e2a6b6ce3b8c248f7dc31451aefca57e3bdf0e48d73ae5043229380a67614c41", [:mix], [], "hexpm"},
   "ex_aws": {:hex, :ex_aws, "2.1.0", "b92651527d6c09c479f9013caa9c7331f19cba38a650590d82ebf2c6c16a1d8a", [:mix], [{:configparser_ex, "~> 2.0", [hex: :configparser_ex, repo: "hexpm", optional: true]}, {:hackney, "1.6.3 or 1.6.5 or 1.7.1 or 1.8.6 or ~> 1.9", [hex: :hackney, repo: "hexpm", optional: true]}, {:jsx, "~> 2.8", [hex: :jsx, repo: "hexpm", optional: true]}, {:poison, ">= 1.2.0", [hex: :poison, repo: "hexpm", optional: true]}, {:sweet_xml, "~> 0.6", [hex: :sweet_xml, repo: "hexpm", optional: true]}, {:xml_builder, "~> 0.1.0", [hex: :xml_builder, repo: "hexpm", optional: true]}], "hexpm"},
diff --git a/test/formatter_test.exs b/test/formatter_test.exs
index 428227d78..bb318b7d5 100644
--- a/test/formatter_test.exs
+++ b/test/formatter_test.exs
@@ -257,4 +257,23 @@ defmodule Pleroma.FormatterTest do
     text = nil
     assert Formatter.get_emoji(text) == []
   end
+
+  describe "/mentions_escape" do
+    test "it returns text with escaped mention names" do
+      text = """
+      @a_breakin_glass@cybre.space
+      (also, little voice inside my head thinking "maybe this will encourage people
+      pronouncing it properly instead of saying _raKEWdo_ ")
+      """
+
+      escape_text = """
+      @a\\_breakin\\_glass@cybre\\.space
+      (also, little voice inside my head thinking \"maybe this will encourage people
+      pronouncing it properly instead of saying _raKEWdo_ \")
+      """
+
+      mentions = [{"@a_breakin_glass@cybre.space", %{}}]
+      assert Formatter.mentions_escape(text, mentions) == escape_text
+    end
+  end
 end