Disable color for formatter file output

CHANGELOG.md

@@ -13,6 +13,7 @@ Please visit [cucumber/CONTRIBUTING.md](https://github.com/cucumber/cucumber/blo
 - Show failed step error details in the summary formatter output
 - Fixed up JRuby examples which weren't running due to anglicisation issues (Pivoted to use English step definitions to help JRuby testing)
 - Fixed up Arabic example which had some incorrect logic for step definition matching (Due to RTL nature of the language)
+- Disable ANSI color by default for console formatter output written with `--out`.
 
 ## [11.1.0] - 2026-06-02
 ### Added

lib/cucumber/cli/options.rb

@@ -435,7 +435,7 @@ def add_tag_limit(tag_limits, tag_name, limit)
       end
 
       def color(color)
-        Cucumber::Term::ANSIColor.coloring = color
+        Cucumber::Term::ANSIColor.coloring = (@options[:color] = color)
       end
 
       def initialize_project

lib/cucumber/formatter/console.rb

@@ -31,27 +31,31 @@ module Console
       include Duration
 
       def format_step(keyword, step_match, status, source_indent)
-        comment = if source_indent
-                    c = indent("# #{step_match.location}", source_indent)
-                    format_string(c, :comment)
-                  else
-                    ''
-                  end
-
-        format = format_for(status, :param)
-        line = keyword + step_match.format_args(format) + comment
-        format_string(line, status)
+        with_formatter_coloring do
+          comment = if source_indent
+                      c = indent("# #{step_match.location}", source_indent)
+                      format_string(c, :comment)
+                    else
+                      ''
+                    end
+
+          format = format_for(status, :param)
+          line = keyword + step_match.format_args(format) + comment
+          format_string(line, status)
+        end
       end
 
       def format_string(input, status)
-        fmt = format_for(status)
-        input.to_s.split("\n").map do |line|
-          if fmt.instance_of?(Proc)
-            fmt.call(line)
-          else
-            fmt % line
-          end
-        end.join("\n")
+        with_formatter_coloring do
+          fmt = format_for(status)
+          input.to_s.split("\n").map do |line|
+            if fmt.instance_of?(Proc)
+              fmt.call(line)
+            else
+              fmt % line
+            end
+          end.join("\n")
+        end
       end
 
       def print_elements(elements, status, kind)
@@ -229,6 +233,35 @@ def indent(string, padding)
 
       FORMATS = Hash.new { |hash, format| hash[format] = method(format).to_proc }
 
+      def with_formatter_coloring
+        original_coloring = Cucumber::Term::ANSIColor.coloring?
+        Cucumber::Term::ANSIColor.coloring = formatter_coloring?
+        yield
+      ensure
+        Cucumber::Term::ANSIColor.coloring = original_coloring
+      end
+
+      def formatter_coloring?
+        options = if instance_variable_defined?(:@options) && @options
+                    @options
+                  elsif instance_variable_defined?(:@config) && @config.respond_to?(:to_hash)
+                    @config.to_hash
+                  else
+                    {}
+                  end
+        return options[:color] if options.key?(:color)
+
+        io = if instance_variable_defined?(:@io)
+               @io
+             elsif instance_variable_defined?(:@config) && @config.respond_to?(:out_stream)
+               @config.out_stream
+             end
+        return Cucumber::Term::ANSIColor.coloring? if io.nil?
+        return false unless io.respond_to?(:tty?)
+
+        io.tty?
+      end
+
       def format_for(*keys)
         key = keys.join('_').to_sym
         fmt = FORMATS[key]

lib/cucumber/formatter/console_counts.rb

@@ -8,6 +8,7 @@ class ConsoleCounts
       include Console
 
       def initialize(config)
+        @config = config
         @summary = Core::Report::Summary.new(config.event_bus)
       end
 

spec/cucumber/formatter/console_spec.rb

@@ -2,6 +2,7 @@
 
 require 'cucumber/configuration'
 require 'cucumber/formatter/console'
+require 'cucumber/step_match'
 
 module Cucumber
   module Formatter
@@ -21,6 +22,53 @@ module Formatter
         res = indent('  a line', -10)
         expect(res).to eq 'a line'
       end
+
+      context 'when coloring console output' do
+        around do |example|
+          original_coloring = Cucumber::Term::ANSIColor.coloring?
+          Cucumber::Term::ANSIColor.coloring = true
+          example.run
+        ensure
+          Cucumber::Term::ANSIColor.coloring = original_coloring
+        end
+
+        it 'uses color by default when the formatter output is a tty' do
+          @io = instance_double(IO, tty?: true)
+          @options = {}
+
+          expect(format_string('undefined', :undefined)).to include("\e[33m")
+        end
+
+        it 'disables color by default when the formatter output is a file' do
+          @io = instance_double(File, tty?: false)
+          @options = {}
+
+          expect(format_string('undefined', :undefined)).to eq 'undefined'
+        end
+
+        it 'allows explicit color to override the formatter output destination' do
+          @io = instance_double(File, tty?: false)
+          @options = { color: true }
+
+          expect(format_string('undefined', :undefined)).to include("\e[33m")
+        end
+
+        it 'allows explicit no-color to override a tty output destination' do
+          @io = instance_double(IO, tty?: true)
+          @options = { color: false }
+
+          expect(format_string('undefined', :undefined)).to eq 'undefined'
+        end
+
+        it 'disables step argument color by default when the formatter output is a file' do
+          @io = instance_double(File, tty?: false)
+          @options = {}
+          step_match = instance_double(Cucumber::StepMatch)
+          allow(step_match).to receive(:format_args) { |format| "I have #{format.call('3')} cukes" }
+
+          expect(format_step('Given ', step_match, :passed, nil)).to eq 'Given I have 3 cukes'
+        end
+      end
     end
   end
 end