Fix issue #6614: Support spaces in @mentions using quotes

lib/rich_text.rb

@@ -4,6 +4,7 @@ module RichText
   DESCRIPTION_MAX_LENGTH = 500
   DESCRIPTION_WORD_BREAK_THRESHOLD_LENGTH = 450
   URL_UNSAFE_CHARS = "[^\\w!#$%&'*+,./:;=?@_~^\\-]"
+  LINK_ATTRIBUTES = 'rel="nofollow noopener noreferrer" dir="auto"'
 
   def self.new(format, text)
     case format
@@ -89,6 +90,7 @@ def sanitize(text)
 
     def linkify(text, mode = :urls)
       ERB::Util.html_escape(text)
+               .then { |html| linkify_users(html) }
                .then { |html| expand_link_shorthands(html) }
                .then { |html| expand_host_shorthands(html) }
                .then { |html| auto_link(html, mode) }
@@ -97,6 +99,22 @@ def linkify(text, mode = :urls)
 
     private
 
+    def linkify_users(text)
+      regex = /(?<!\w)@(?:“([^”]+?)”|”([^”]+?)”|‘([^’]+?)’|’([^’]+?)’|"([^"]+?)"|'([^']+?)'|(\w+))/
+
+      text.gsub(regex) do |match|
+        name = ::Regexp.last_match.captures.compact.first
+        next match unless name
+
+        slug_name = name.tr("“”‘’", %q(""''
+))
+        slug = ERB::Util.url_encode(slug_name)
+
+        safe_match = match.sub("@", "&#64;")
+        "<a href=\"/user/#{slug}\" #{LINK_ATTRIBUTES}>#{safe_match}</a>"
+      end
+    end
+
     def gsub_pairs_for_linkify_detection
       Array
         .wrap(Settings.linkify&.detection_rules)
@@ -128,8 +146,7 @@ def expand_host_shorthands(text)
     end
 
     def auto_link(text, mode)
-      link_attr = 'rel="nofollow noopener noreferrer" dir="auto"'
-      Rinku.auto_link(text, mode, link_attr) { |url| format_link_text(url) }
+      Rinku.auto_link(text, mode, LINK_ATTRIBUTES) { |url| format_link_text(url) }
     end
 
     def format_link_text(url)

test/lib/rich_text_test.rb

@@ -193,7 +193,6 @@ def test_markdown_to_html
   end
 
   def test_markdown_table_alignment
-    # Ensure that kramdown table alignment styles are converted to bootstrap classes
     markdown_table = <<~MARKDOWN
       | foo  | bar |
       |:----:|----:|
@@ -225,6 +224,14 @@ def test_text_to_html_linkify
     end
   end
 
+  def test_linkify_username_with_space
+    with_settings(:linkify => { :detection_rules => [{ :patterns => ["@(?<username>\\w+)"], :path_template => "user/\\k<username>" }] }) do
+      text = 'Hello @"Open Mapper"'
+      html = RichText.new("markdown", text).to_html
+      assert_match %r{<a href="/user/Open%20Mapper" #{RichText::LINK_ATTRIBUTES}>&#64;[“”]Open Mapper[“”]</a>}o, html
+    end
+  end
+
   def test_text_to_html_linkify_replace
     with_settings(:linkify_hosts => ["replace-me.example.com"], :linkify_hosts_replacement => "repl.example.com") do
       r = RichText.new("text", "foo https://replace-me.example.com/some/path?query=te<st&limit=20>10#result12 bar")
@@ -237,6 +244,18 @@ def test_text_to_html_linkify_replace
     end
   end
 
+  def test_linkify_username_with_quotes
+    text = "Hello @'\"Yo\"'"
+    html = RichText.new("markdown", text).to_html
+    assert_match %r{<a href="/user/%22Yo%22" #{RichText::LINK_ATTRIBUTES}>&#64;[‘'’]“Yo”[‘'’]</a>}o, html
+  end
+
+  def test_linkify_short_username
+    text = "Hello @Yo"
+    html = RichText.new("markdown", text).to_html
+    assert_match %r{<a href="/user/Yo" #{RichText::LINK_ATTRIBUTES}>&#64;Yo</a>}o, html
+  end
+
   def test_text_to_html_linkify_recognize
     with_settings(:linkify_hosts => ["replace-me.example.com"], :linkify_hosts_replacement => "repl.example.com") do
       r = RichText.new("text", "foo repl.example.com/some/path?query=te<st&limit=20>10#result12 bar")
@@ -356,8 +375,10 @@ def test_text_to_html_linkify_recognize_path
     with_settings(:linkify => { :detection_rules => [{ :patterns => ["@(?<username>\\w+)"], :path_template => "user/\\k<username>" }] }) do
       r = RichText.new("text", "foo @example bar")
       assert_html r do
-        assert_dom "a", :count => 1, :text => "http://test.host/user/example" do
-          assert_dom "> @href", "http://test.host/user/example"
+        # We now expect the visible text to be "@example", not the full URL
+        assert_dom "a", :count => 1, :text => "@example" do
+          # We now expect a standard relative URL
+          assert_dom "> @href", "/user/example"
           assert_dom "> @rel", "nofollow noopener noreferrer"
         end
       end