Various GitHub Onebox improvements (#13163)

* FIX: Improve GitHub folder regexp in Onebox

It used to match any GitHub URL that was not matched by the other GitHub
Oneboxes and it did not do a good job at handling those. With this
change, the generic Onebox will handle the remaining URLs.

* FEATURE: Add Onebox for GitHub Actions

* FEATURE: Add Onebox for PR check runs

* FIX: Remove image from GitHub folder Oneboxes

It is a generic, auto-generated image which does not provide any value.

* DEV: Add tests

* FIX: Strip HTML comments from PR body

lib/onebox/engine/github_actions_onebox.rb

@@ -0,0 +1,87 @@
+# frozen_string_literal: true
+
+require_relative '../mixins/github_body'
+
+module Onebox
+  module Engine
+    class GithubActionsOnebox
+      include Engine
+      include LayoutSupport
+      include JSON
+
+      matches_regexp(/^https?:\/\/(?:www\.)?(?:(?:\w)+\.)?github\.com\/(?<org>.+)\/(?<repo>.+)\/(actions\/runs\/[[:digit:]]+|pull\/[[:digit:]]*\/checks\?check_run_id=[[:digit:]]+)/)
+      always_https
+
+      def url
+        if type == :actions_run
+          "https://api.github.com/repos/#{match[:org]}/#{match[:repo]}/actions/runs/#{match[:run_id]}"
+        elsif type == :pr_run
+          "https://api.github.com/repos/#{match[:org]}/#{match[:repo]}/check-runs/#{match[:check_run_id]}"
+        end
+      end
+
+      def self.priority
+        90 # overlaps with GithubPullRequestOnebox
+      end
+
+      private
+
+      def match_url
+        return if defined?(@match) && defined?(@type)
+
+        if match = @url.match(/^https?:\/\/(?:www\.)?(?:(?:\w)+\.)?github\.com\/(?<org>.+)\/(?<repo>.+)\/actions\/runs\/(?<run_id>[[:digit:]]+)/)
+          @match = match
+          @type = :actions_run
+        end
+
+        if match = @url.match(/^https?:\/\/(?:www\.)?(?:(?:\w)+\.)?github\.com\/(?<org>.+)\/(?<repo>.+)\/pull\/(?<pr_id>[[:digit:]]*)\/checks\?check_run_id=(?<check_run_id>[[:digit:]]+)/)
+          @match = match
+          @type = :pr_run
+        end
+      end
+
+      def match
+        return @match if defined?(@match)
+
+        match_url
+        @match
+      end
+
+      def type
+        return @type if defined?(@type)
+
+        match_url
+        @type
+      end
+
+      def data
+        status = "unknown"
+        if raw["status"] == "completed"
+          if raw["conclusion"] == "success"
+            status = "success"
+          elsif raw["conclusion"] == "failure"
+            status = "failure"
+          elsif raw["conclusion"] == "cancelled"
+          end
+        elsif raw["status"] == "in_progress"
+          status = "pending"
+        end
+
+        title = if type == :actions_run
+          raw["head_commit"]["message"].lines.first
+        elsif type == :pr_run
+          pr_url = "https://api.github.com/repos/#{match[:org]}/#{match[:repo]}/pulls/#{match[:pr_id]}"
+          ::MultiJson.load(URI.open(pr_url, read_timeout: timeout))["title"]
+        end
+
+        {
+          link: @url,
+          title: title,
+          name: raw["name"],
+          run_number: raw["run_number"],
+          status => true,
+        }
+      end
+    end
+  end
+end

lib/onebox/engine/github_folder_onebox.rb

@@ -7,14 +7,9 @@ module Onebox
       include StandardEmbed
       include LayoutSupport
 
-      matches_regexp(/^https?:\/\/(?:www\.)?(?:(?:\w)+\.)?(github)\.com[\:\d]*(\/[^\/]+){2}/)
+      matches_regexp(/^https?:\/\/(?:www\.)?(?:(?:\w)+\.)?(github)\.com[\:\d]*(\/[^\/]+){2}\/tree/)
       always_https
 
-      def self.priority
-        # This engine should have lower priority than the other Github engines
-        150
-      end
-
       private
 
       def data
@@ -46,7 +41,6 @@ module Onebox
 
         {
           link: url,
-          image: og.image,
           title: Onebox::Helpers.truncate(title, 250),
           path: display_path,
           description: display_description,