Change pipeline to inject progress bar instance only once

lib/tty/progressbar.rb

@@ -39,7 +39,6 @@ class ProgressBar
 
     def_delegators :@meter, :rate, :mean_rate
 
-    def_delegator :@formatter, :use
 
     # Determine terminal width
     #
@@ -107,7 +106,7 @@ def initialize(format, options = {})
       @meter     = TTY::ProgressBar::Meter.new(interval)
       @callbacks = Hash.new { |h, k| h[k] = [] }
 
-      @formatter.load
+      @formatter.load(self)
       reset
 
       @first_render = true
@@ -143,6 +142,19 @@ def attach_to(multibar)
       @multibar = multibar
     end
 
+    # Use custom token formatter
+    #
+    # @param [Object] formatter_class
+    #   the formatter class to add to formatting pipeline
+    #
+    # @api public
+    def use(formatter_class)
+      unless formatter_class.is_a?(Class)
+        raise ArgumentError, "Formatter needs to be a class"
+      end
+      @formatter.use(formatter_class.new(self))
+    end
+
     # Start progression by drawing bar and setting time
     #
     # @api public
@@ -287,7 +299,7 @@ def render
         update(inset: self.class.display_columns(characters_in))
       end
 
-      formatted = @formatter.decorate(self, @format)
+      formatted = @formatter.decorate(@format)
       @tokens.each do |token, val|
         formatted = formatted.gsub(":#{token}", val)
       end

lib/tty/progressbar/formatter.rb

@@ -30,19 +30,19 @@ def initialize(pipeline = nil)
       # Prepare default pipeline formatters
       #
       # @api private
-      def load
-        @pipeline.use TTY::ProgressBar::CurrentFormatter
-        @pipeline.use TTY::ProgressBar::TotalFormatter
-        @pipeline.use TTY::ProgressBar::TotalByteFormatter
-        @pipeline.use TTY::ProgressBar::ElapsedFormatter
-        @pipeline.use TTY::ProgressBar::EstimatedFormatter
-        @pipeline.use TTY::ProgressBar::PercentFormatter
-        @pipeline.use TTY::ProgressBar::ByteFormatter
-        @pipeline.use TTY::ProgressBar::ByteRateFormatter
-        @pipeline.use TTY::ProgressBar::RateFormatter
-        @pipeline.use TTY::ProgressBar::MeanRateFormatter
-        @pipeline.use TTY::ProgressBar::MeanByteFormatter
-        @pipeline.use TTY::ProgressBar::BarFormatter
+      def load(progress)
+        @pipeline.use TTY::ProgressBar::CurrentFormatter.new(progress)
+        @pipeline.use TTY::ProgressBar::TotalFormatter.new(progress)
+        @pipeline.use TTY::ProgressBar::TotalByteFormatter.new(progress)
+        @pipeline.use TTY::ProgressBar::ElapsedFormatter.new(progress)
+        @pipeline.use TTY::ProgressBar::EstimatedFormatter.new(progress)
+        @pipeline.use TTY::ProgressBar::PercentFormatter.new(progress)
+        @pipeline.use TTY::ProgressBar::ByteFormatter.new(progress)
+        @pipeline.use TTY::ProgressBar::ByteRateFormatter.new(progress)
+        @pipeline.use TTY::ProgressBar::RateFormatter.new(progress)
+        @pipeline.use TTY::ProgressBar::MeanRateFormatter.new(progress)
+        @pipeline.use TTY::ProgressBar::MeanByteFormatter.new(progress)
+        @pipeline.use TTY::ProgressBar::BarFormatter.new(progress)
       end
     end # Formatter
   end # ProgressBar

lib/tty/progressbar/pipeline.rb

@@ -19,24 +19,29 @@ def initialize(formatters = [])
       # Add a new formatter
       #
       # @example
-      #   use(TTY::ProgressBar::TotalFormatter)
+      #   use(TTY::ProgressBar::TotalFormatter.new(progress_bar))
       #
       # @api public
       def use(formatter)
-        formatters << proc { |progress| formatter.new(progress) }
+        formatters << formatter
       end
 
       # Decorate the tokenized string with actual values
       #
+      # @example
+      #   decorate("[:bar] :current :elapsed")
+      #
+      # @param [String] tokenized
+      #   the string with tokens
+      #
       # @return [nil]
       #
       # @api private
-      def decorate(progress, tokenized)
+      def decorate(tokenized)
         base = tokenized.dup
         formatters.inject(base) do |formatted, formatter|
-          instance = formatter.call(progress)
-          if instance.respond_to?(:matches?) && instance.matches?(formatted)
-            instance.format(formatted)
+          if formatter.respond_to?(:matches?) && formatter.matches?(formatted)
+            formatter.format(formatted)
           else
             formatted
           end

spec/perf/render_spec.rb

@@ -28,14 +28,14 @@
     }.at_most(10).times
   end
 
-  it "performs bar rendering 2.3k i/s" do
+  it "performs bar rendering 2.4k i/s" do
     output = StringIO.new
     progress = described_class.new("[:bar]", output: output, total: 10,
                                              width: 10)
 
     expect {
       progress.advance
       progress.reset
-    }.to perform_at_least(2300).ips
+    }.to perform_at_least(2400).ips
   end
 end

spec/unit/custom_formatter_spec.rb

@@ -23,4 +23,14 @@ def format(value)
     output.rewind
     expect(output.read).to eq("\e[1GHello")
   end
+
+  it "enforces class formatter" do
+    progress = TTY::ProgressBar.new(":hi", output: output, total: 10)
+    stub_const("HiFormatter", Class.new)
+    formatter = HiFormatter.new
+
+    expect {
+      progress.use(formatter)
+    }.to raise_error(ArgumentError, "Formatter needs to be a class")
+  end
 end

spec/unit/pipeline_spec.rb

@@ -2,16 +2,17 @@
   subject(:pipeline) { described_class.new }
 
   it "decorates tokenized string with pipeline formatters" do
-    pipeline.use TTY::ProgressBar::CurrentFormatter
-    pipeline.use TTY::ProgressBar::TotalFormatter
     progress_bar = double(current: '3', total: '10')
+    pipeline.use TTY::ProgressBar::CurrentFormatter.new(progress_bar)
+    pipeline.use TTY::ProgressBar::TotalFormatter.new(progress_bar)
     tokenized = "[:current/:total]"
-    expect(pipeline.decorate(progress_bar, tokenized)).to eq("[3/10]")
+    expect(pipeline.decorate(tokenized)).to eq("[3/10]")
   end
 
   it "enumerates pipeline formatters" do
-    pipeline.use TTY::ProgressBar::CurrentFormatter
-    pipeline.use TTY::ProgressBar::TotalFormatter
+    progress_bar = double(current: '3', total: '10')
+    pipeline.use TTY::ProgressBar::CurrentFormatter.new(progress_bar)
+    pipeline.use TTY::ProgressBar::TotalFormatter.new(progress_bar)
     yielded = []
     pipeline.each { |formatter| yielded << formatter }
     expect(yielded.size).to eq(2)