Prefer String#b over force_encoding and avoid mutating strings

bin/passenger-install-nginx-module

@@ -603,12 +603,7 @@ private
     # We do this instead of using #file, for Ruby 1.8.5 support.
     digest = Digest::SHA256.new
     File.open(path, "rb") do |f|
-      if Gem::Version.new(RUBY_VERSION) >= Gem::Version.new('2.3.0')
-        buf = String.new(encoding: Encoding::BINARY)
-      else
-        buf = ""
-        buf.force_encoding('binary') if buf.respond_to?(:force_encoding)
-      end
+      buf = ''.b
       while !f.eof?
         f.read(1024 * 16, buf)
         digest.update(buf)

dev/ruby_server.rb

@@ -135,12 +135,7 @@ def start_thread
   def handle_next_client(forward_connection)
     client = @server.accept
     begin
-      if Gem::Version.new(RUBY_VERSION) >= Gem::Version.new('2.3.0')
-        buffer = String.new(encoding: Encoding::BINARY)
-      else
-        buffer = ""
-        buffer.force_encoding('binary') if buffer.respond_to?(:force_encoding)
-      end
+      buffer = "".b
       while true
         begin
           read_header(client, buffer)

src/ruby_supportlib/phusion_passenger/admin_tools/memory_stats.rb

@@ -250,7 +250,7 @@ def list_processes(options)
           ps_output = `#{ps} -w -o pid,ppid,nlwp,vsz,rss,%cpu,command`
           threads_known = true
         end
-        list = force_binary(ps_output).split("\n")
+        list = ps_output.b.split("\n")
         list.shift
         list.each do |line|
           line.gsub!(/^ */, '')
@@ -297,16 +297,6 @@ def determine_private_dirty_rss(pid)
       rescue Errno::EACCES, Errno::ENOENT, Errno::ESRCH
         return nil
       end
-
-      if ''.respond_to?(:force_encoding)
-        def force_binary(str)
-          str.force_encoding('binary')
-        end
-      else
-        def force_binary(str)
-          str
-        end
-      end
     end
 
   end # module AdminTools

src/ruby_supportlib/phusion_passenger/request_handler/thread_handler.rb

@@ -101,12 +101,7 @@ def install
       def main_loop(finish_callback)
         socket_wrapper = Utils::UnseekableSocket.new
         channel        = MessageChannel.new
-        if Gem::Version.new(RUBY_VERSION) >= Gem::Version.new('2.3.0')
-          buffer = String.new(encoding: Encoding::BINARY)
-        else
-          buffer = ""
-          buffer.force_encoding('binary') if buffer.respond_to?(:force_encoding)
-        end
+        buffer         = ''.b
 
         begin
           finish_callback.call

src/ruby_supportlib/phusion_passenger/standalone/start_command/nginx_engine.rb

@@ -322,12 +322,8 @@ def default_group_for(username)
         end
 
         def serialize_strset(*items)
-          if "".respond_to?(:force_encoding)
-            items = items.map { |x| x.force_encoding('binary') }
-            null  = "\0".force_encoding('binary')
-          else
-            null  = "\0"
-          end
+          items = items.map(&:b)
+          null  = "\0".b
           return [items.join(null)].pack('m*').gsub("\n", "").strip
         end
 

src/ruby_supportlib/phusion_passenger/utils/unseekable_socket.rb

@@ -180,9 +180,9 @@ def gets
         if @simulate_eof
           length, buffer = args
           if buffer
-            buffer.replace(binary_string(""))
+            buffer.replace("".b)
           else
-            buffer = binary_string("")
+            buffer = "".b
           end
           if length
             return nil
@@ -292,16 +292,6 @@ def annotate(exception)
       def raise_error_because_activity_disallowed!
         raise IOError, "It is not possible to read or write from the client socket because the current."
       end
-
-      if ''.respond_to?(:force_encoding)
-        def binary_string(str)
-          return ''.force_encoding('binary')
-        end
-      else
-        def binary_string(str)
-          return ''
-        end
-      end
     end
 
   end # module Utils

test/integration_tests/native_packaging_spec.rb

@@ -135,9 +135,8 @@ module PhusionPassenger
 describe "A natively packaged Phusion Passenger" do
   def capture_output(command)
     output = `#{command}`.strip
-    if output.respond_to?(:force_encoding)
-      output.force_encoding('utf-8')
-    end
+    output.force_encoding(Encoding::UTF_8)
+
     if $?.exitstatus == 0
       return output
     else

test/integration_tests/shared/example_webapp_tests.rb

@@ -64,9 +64,9 @@
         io.read
       end
       response.should ==
-        binary_string("name 1 = Kotonoha\n") <<
-        binary_string("name 2 = Sekai\n") <<
-        binary_string("data = ") << static_file.read
+        "name 1 = Kotonoha\n".b <<
+        "name 2 = Sekai\n".b <<
+        "data = ".b << static_file.read
     ensure
       static_file.close
     end

test/integration_tests/standalone_tests.rb

@@ -32,9 +32,8 @@ def sh(*command)
 
   def capture_output(command)
     output = `#{command} 2>&1`.strip
-    if output.respond_to?(:force_encoding)
-      output.force_encoding('utf-8')
-    end
+    output.force_encoding(Encoding::UTF_8)
+
     if $?.exitstatus == 0
       output
     else

test/stub/rack/config.ru

@@ -50,8 +50,8 @@ app = lambda do |env|
     text_response("This is the uncached version of /cached")
   when '/upload_with_params'
     req = Rack::Request.new(env)
-    name1 = binary_string(req.params["name1"])
-    name2 = binary_string(req.params["name2"])
+    name1 = req.params["name1"].b
+    name2 = req.params["name2"].b
     file = req.params["data"][:tempfile]
     file.binmode
     text_response(

test/stub/rack/library.rb

@@ -1,16 +1,6 @@
 # encoding: binary
 
 def text_response(body)
-  body = binary_string(body.to_s)
+  body = body.to_s.b
   return [200, { "Content-Type" => "text/plain", "Content-Length" => body.size.to_s }, [body]]
 end
-
-if "".respond_to?(:force_encoding)
-  def binary_string(str)
-    return str.force_encoding("binary")
-  end
-else
-  def binary_string(str)
-    return str
-  end
-end

test/support/test_helper.rb

@@ -350,16 +350,6 @@ def inspect_server(name)
       return instance
     end
   end
-
-  if "".respond_to?(:force_encoding)
-    def binary_string(str)
-      return str.force_encoding("binary")
-    end
-  else
-    def binary_string(str)
-      return str
-    end
-  end
 end
 
 File.class_eval do