Add color setting to control when colors are applied

lib/tty/markdown.rb

@@ -108,15 +108,18 @@ module Markdown
     #   the color names for markdown elements
     # @param [Integer] :width
     #   the width at which to wrap content
+    # @param [Boolean] :color
+    #   when to enable coloring out of always, never or auto
     # @param [Hash] :doc_opts
     #   the markdown document parser options
     #
     # @api public
     def parse(source, width: TTY::Screen.width, theme: THEME, indent: 2,
-                      colors: TTY::Color.mode, symbols: {}, **doc_opts)
+                      colors: TTY::Color.mode, symbols: {}, color: :auto,
+                      **doc_opts)
       convert_options = { width: width, indent: indent, theme: theme,
                           colors: colors, symbols: build_symbols(symbols),
-                          input: "KramdownExt" }
+                          input: "KramdownExt", enabled: color_enabled(color) }
       doc = Kramdown::Document.new(source, convert_options.merge(doc_opts))
       Converter.convert(doc.root, doc.options).join
     end
@@ -130,6 +133,19 @@ def parse_file(path, **options)
     end
     module_function :parse_file
 
+    # Convert color setting to Pastel setting
+    #
+    # @api private
+    def color_enabled(color)
+      case color.to_s
+      when "always" then true
+      when "never"  then false
+      else nil
+      end
+    end
+    module_function :color_enabled
+    private_class_method :color_enabled
+
     # Extract and build symbols
     #
     # @api private

lib/tty/markdown/converter.rb

@@ -19,10 +19,10 @@ def initialize(root, options = {})
         super
         @current_indent = 0
         @indent = options[:indent]
-        mode = options[:colors]
-        pastel_opts = mode <= 0 ? { enabled: false } : {}
-        @pastel = Pastel.new(**pastel_opts)
-        @color_opts = { mode: mode, color: @pastel.yellow.detach }
+        @pastel = Pastel.new(enabled: options[:enabled])
+        @color_opts = { mode: options[:colors],
+                        color: @pastel.yellow.detach,
+                        enabled: options[:enabled] }
         @width = options[:width]
         @theme = options[:theme].each_with_object({}) do |(key, val), acc|
                    acc[key] = Array(val)

lib/tty/markdown/syntax_highlighter.rb

@@ -45,15 +45,18 @@ def guess_lang(code)
       #   the color mode supported by the terminal
       # @param [String] lang
       #   the code snippet language
+      # @param [Boolean] enabled
+      #   whether or not coloring is enabled
       # @param [Proc] color
       #   the fallback coloring
       #
       # @api public
-      def highlight(code, mode: 256, lang: nil, color: ->(line) { line })
+      def highlight(code, mode: 256, lang: nil, enabled: nil,
+                    color: ->(line) { line })
         lang = guess_lang(code) if lang.nil?
         lexer = Rouge::Lexer.find_fancy(lang, code) || Rouge::Lexers::PlainText
 
-        if mode <= 0
+        if enabled == false
           code
         elsif 256 <= mode
           formatter = Rouge::Formatters::Terminal256.new

spec/unit/codeblock_spec.rb

@@ -157,7 +157,7 @@ def say
 end
 ```
     TEXT
-    parsed = TTY::Markdown.parse(markdown, colors: 0)
+    parsed = TTY::Markdown.parse(markdown, color: :never)
     expect(parsed).to eq([
      "class Greeter",
      "  def say",

spec/unit/color_spec.rb

@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+RSpec.describe TTY::Markdown, "color" do
+  it "switches off coloring for all elements" do
+    markdown =<<-TEXT
+# Header
+
+**bold**
+
+```
+class Greeter
+  def say
+  end
+end
+```
+    TEXT
+    parsed = TTY::Markdown.parse(markdown, color: :never)
+
+    expect(parsed).to eq([
+      "Header",
+      "",
+      "bold",
+      "",
+      "class Greeter",
+      "  def say",
+      "  end",
+      "end"
+    ].join("\n"))
+  end
+end

spec/unit/header_spec.rb

@@ -8,7 +8,7 @@
   end
 
   it "disables top level header coloring" do
-    parsed = TTY::Markdown.parse("Header1\n======", colors: 0)
+    parsed = TTY::Markdown.parse("Header1\n======", color: :never)
 
     expect(parsed).to eq("Header1\n")
   end