1 files changed, 81 insertions, 0 deletions
diff --git a/Library/Homebrew/readall.rb b/Library/Homebrew/readall.rb
new file mode 100644
index 000000000..4d09226f5
--- /dev/null
+++ b/Library/Homebrew/readall.rb
@@ -0,0 +1,81 @@
+require "formula"
+require "tap"
+require "thread"
+require "readall"
+
+module Readall
+  class << self
+    def valid_ruby_syntax?(ruby_files)
+      ruby_files_queue = Queue.new
+      ruby_files.each { |f| ruby_files_queue << f }
+      failed = false
+      workers = (0...Hardware::CPU.cores).map do
+        Thread.new do
+          begin
+            while rb = ruby_files_queue.pop(true)
+              # As a side effect, print syntax errors/warnings to `$stderr`.
+              failed = true if syntax_errors_or_warnings?(rb)
+            end
+          rescue ThreadError # ignore empty queue error
+          end
+        end
+      end
+      workers.each(&:join)
+      !failed
+    end
+
+    def valid_aliases?(alias_dirs)
+      failed = false
+      alias_dirs.each do |alias_dir|
+        next unless alias_dir.directory?
+        alias_dir.children.each do |f|
+          next unless f.symlink?
+          next if f.file?
+          onoe "Broken alias: #{f}"
+          failed = true
+        end
+      end
+      !failed
+    end
+
+    def valid_formulae?(formulae)
+      failed = false
+      formulae.each do |file|
+        begin
+          Formulary.factory(file)
+        rescue Interrupt
+          raise
+        rescue Exception => e
+          onoe "Invalid formula: #{file}"
+          puts e
+          failed = true
+        end
+      end
+      !failed
+    end
+
+    def valid_tap?(tap, options = {})
+      failed = false
+      if options[:aliases]
+        valid_aliases = valid_aliases?([tap.alias_dir])
+        failed = true unless valid_aliases
+      end
+      valid_formulae = valid_formulae?(tap.formula_files)
+      failed = true unless valid_formulae
+      !failed
+    end
+
+    private
+
+    def syntax_errors_or_warnings?(rb)
+      # Retrieve messages about syntax errors/warnings printed to `$stderr`, but
+      # discard a `Syntax OK` printed to `$stdout` (in absence of syntax errors).
+      messages = Utils.popen_read("#{RUBY_PATH} -c -w #{rb} 2>&1 >/dev/null")
+      $stderr.print messages
+
+      # Only syntax errors result in a non-zero status code. To detect syntax
+      # warnings we also need to inspect the output to `$stderr`.
+      !$?.success? || !messages.chomp.empty?
+    end
+  end
+end