Merge pull request #5740 from reitermarkus/automerge

Add `brew cask automerge` command.

Library/Homebrew/cask/cmd.rb

@@ -9,6 +9,7 @@ require "cask/cmd/options"
 
 require "cask/cmd/abstract_command"
 require "cask/cmd/audit"
+require "cask/cmd/automerge"
 require "cask/cmd/cat"
 require "cask/cmd/create"
 require "cask/cmd/doctor"

Library/Homebrew/cask/cmd/automerge.rb

@@ -0,0 +1,124 @@
+# frozen_string_literal: true
+
+require "cask/cmd/abstract_internal_command"
+require "tap"
+require "utils/formatter"
+require "utils/github"
+
+module Cask
+  class Cmd
+    class Automerge < AbstractInternalCommand
+      OFFICIAL_CASK_TAPS = [
+        "homebrew/cask",
+        "homebrew/cask-drivers",
+        "homebrew/cask-eid",
+        "homebrew/cask-fonts",
+        "homebrew/cask-versions",
+      ].freeze
+
+      def run
+        taps = OFFICIAL_CASK_TAPS.map(&Tap.public_method(:fetch))
+
+        access = taps.all? { |tap| GitHub.write_access?(tap.full_name) }
+        raise "This command may only be run by Homebrew maintainers." unless access
+
+        Homebrew.install_gem! "git_diff"
+        require "git_diff"
+
+        failed = []
+
+        taps.each do |tap|
+          open_pull_requests = GitHub.pull_requests(tap.full_name, state: :open, base: "master")
+
+          open_pull_requests.each do |pr|
+            next unless passed_ci(pr)
+            next unless check_diff(pr)
+
+            number = pr["number"]
+            sha = pr.dig("head", "sha")
+
+            print "#{Formatter.url(pr["html_url"])} "
+
+            retried = false
+
+            begin
+              GitHub.merge_pull_request(
+                tap.full_name,
+                number: number, sha: sha,
+                merge_method: :squash,
+                commit_message: "Squashed and auto-merged via `brew cask automerge`."
+              )
+              puts "#{Tty.bold}#{Formatter.success("✔")}#{Tty.reset}"
+            rescue
+              unless retried
+                retried = true
+                sleep 5
+                retry
+              end
+
+              puts "#{Tty.bold}#{Formatter.error("✘")}#{Tty.reset}"
+              failed << pr["html_url"]
+            end
+          end
+        end
+
+        return if failed.empty?
+        $stderr.puts
+        raise CaskError, "Failed merging the following PRs:\n#{failed.join("\n")}"
+      end
+
+      def passed_ci(pr)
+        statuses = GitHub.open_api(pr["statuses_url"])
+
+        latest_pr_status = statuses.select { |status| status["context"] == "continuous-integration/travis-ci/pr" }
+                                   .max_by { |status| Time.parse(status["updated_at"]) }
+
+        latest_pr_status&.fetch("state") == "success"
+      end
+
+      def check_diff(pr)
+        diff_url = pr["diff_url"]
+
+        output, _, status = curl_output("--location", diff_url)
+
+        return false unless status.success?
+
+        diff = GitDiff.from_string(output)
+
+        diff_is_single_cask(diff) && diff_only_version_or_checksum_changed(diff)
+      end
+
+      def diff_is_single_cask(diff)
+        return false unless diff.files.count == 1
+        file = diff.files.first
+        return false unless file.a_path == file.b_path
+        file.a_path.match?(%r{\ACasks/[^/]+\.rb\Z})
+      end
+
+      def diff_only_version_or_checksum_changed(diff)
+        lines = diff.files.flat_map(&:hunks).flat_map(&:lines)
+
+        additions = lines.select(&:addition?)
+        deletions = lines.select(&:deletion?)
+        changed_lines = deletions + additions
+
+        return false if additions.count != deletions.count
+        return false if additions.count > 2
+
+        changed_lines.all? { |line| diff_line_is_version(line.to_s) || diff_line_is_sha256(line.to_s) }
+      end
+
+      def diff_line_is_sha256(line)
+        line.match?(/\A[+-]\s*sha256 '[0-9a-f]{64}'\Z/)
+      end
+
+      def diff_line_is_version(line)
+        line.match?(/\A[+-]\s*version '[^']+'\Z/)
+      end
+
+      def self.help
+        "automatically merge “simple” Cask pull requests"
+      end
+    end
+  end
+end

Library/Homebrew/utils/github.rb

@@ -124,9 +124,9 @@ module GitHub
     @api_credentials_error_message ||= begin
       unauthorized = (response_headers["http/1.1"] == "401 Unauthorized")
       scopes = response_headers["x-accepted-oauth-scopes"].to_s.split(", ")
-      needed_human_scopes = needed_scopes.join(", ")
-      needed_human_scopes = "none" if needed_human_scopes.empty?
-      if !unauthorized && scopes.empty?
+      if unauthorized && scopes.empty?
+        needed_human_scopes = needed_scopes.join(", ")
+        needed_human_scopes = "none" if needed_human_scopes.empty?
         credentials_scopes = response_headers["x-oauth-scopes"]
 
         case GitHub.api_credentials_type
@@ -154,7 +154,7 @@ module GitHub
     end
   end
 
-  def open_api(url, data: nil, scopes: [].freeze)
+  def open_api(url, data: nil, request_method: nil, scopes: [].freeze)
     # This is a no-op if the user is opting out of using the GitHub API.
     return block_given? ? yield({}) : {} if ENV["HOMEBREW_NO_GITHUB_API"]
 
@@ -184,6 +184,10 @@ module GitHub
         data_tmpfile.write data
         data_tmpfile.close
         args += ["--data", "@#{data_tmpfile.path}"]
+
+        if request_method
+          args += ["--request", request_method.to_s]
+        end
       end
 
       args += ["--dump-header", headers_tmpfile.path]
@@ -270,6 +274,31 @@ module GitHub
     search_issues(name, state: "open", repo: "#{tap.user}/homebrew-#{tap.repo}", in: "title")
   end
 
+  def user
+    @user ||= open_api("#{API_URL}/user")
+  end
+
+  def permission(repo, user)
+    open_api("#{API_URL}/repos/#{repo}/collaborators/#{user}/permission")
+  end
+
+  def write_access?(repo, user = nil)
+    user ||= self.user["login"]
+    ["admin", "write"].include?(permission(repo, user)["permission"])
+  end
+
+  def pull_requests(repo, base:, state: :open, **_options)
+    url = "#{API_URL}/repos/#{repo}/pulls?#{URI.encode_www_form(base: base, state: state)}"
+    open_api(url)
+  end
+
+  def merge_pull_request(repo, number:, sha:, merge_method:, commit_message: nil)
+    url = "#{API_URL}/repos/#{repo}/pulls/#{number}/merge"
+    data = { sha: sha, merge_method: merge_method }
+    data[:commit_message] = commit_message if commit_message
+    open_api(url, data: data, request_method: :PUT, scopes: CREATE_ISSUE_FORK_OR_PR_SCOPES)
+  end
+
   def print_pull_requests_matching(query)
     open_or_closed_prs = search_issues(query, type: "pr", user: "Homebrew")