Change undecorate to recognise nested colors and assign correct attri…

…butes (closes #24)

lib/pastel/color_parser.rb

@@ -41,14 +41,13 @@ def self.parse(text)
         char = scanner.getch
         # match control
         if char == ESC && (delim = scanner.getch) == CSI
-          if scanner.scan(/^0m/)
+          if scanner.scan(/^0?m/) # reset
             unpack_ansi(ansi_stack) { |attr, name| state[attr] = name }
             ansi_stack = []
           elsif scanner.scan(/^([1-9;:]+)m/)
             # ansi codes separated by text
             if !text_chunk.empty? && !ansi_stack.empty?
               unpack_ansi(ansi_stack) { |attr, name| state[attr] = name }
-              ansi_stack = []
             end
             scanner[1].split(/:|;/).each do |code|
               ansi_stack << code
@@ -74,7 +73,7 @@ def self.parse(text)
       if !ansi_stack.empty?
         unpack_ansi(ansi_stack) { |attr, name| state[attr] = name}
       end
-      if state.values.any? { |val| !val.empty? }
+      if !state[:text].to_s.empty?
         result.push(state)
       end
       result
@@ -89,10 +88,8 @@ def self.parse(text)
     #
     # @api private
     def self.unpack_ansi(ansi_stack)
-      ansi_stack.each do |ansi|
-        name = ansi_for(ansi)
-        attr = attribute_for(ansi)
-        yield attr, name
+      ansi_stack.each do |code|
+        yield(attribute_name(code), color_name(code))
       end
     end
 
@@ -104,7 +101,7 @@ def self.unpack_ansi(ansi_stack)
     # @return [Symbol]
     #
     # @api private
-    def self.attribute_for(ansi)
+    def self.attribute_name(ansi)
       if ANSI.foreground?(ansi)
         :foreground
       elsif ANSI.background?(ansi)
@@ -114,9 +111,13 @@ def self.attribute_for(ansi)
       end
     end
 
+    # Convert ANSI code to color name
+    #
+    # @return [String]
+    #
     # @api private
-    def self.ansi_for(ansi)
-      ATTRIBUTES.key(ansi.to_i)
+    def self.color_name(ansi_code)
+      ATTRIBUTES.key(ansi_code.to_i)
     end
   end # Parser
 end # Pastel

spec/unit/color_parser_spec.rb

@@ -64,4 +64,44 @@
       {text: "\eA foo bar ESC\e"}
     ])
   end
+
+  it "parses styles from parent text in nested text" do
+    pastel = Pastel.new
+    colored = pastel.bold.on_yellow("foo" + pastel.blue("bar") + "baz")
+    parsed = parser.parse(colored)
+
+    expect(parsed).to eq([
+      {text: "foo", style: :bold, background: :on_yellow},
+      {text: "bar", foreground: :blue, style: :bold, background: :on_yellow},
+      {text: "baz", style: :bold, background: :on_yellow}
+    ])
+  end
+
+  it "parses color when overriden in nested text" do
+    pastel = Pastel.new
+    colored = pastel.yellow.on_red("foo" + pastel.green.bold.on_cyan("bar") + "baz")
+    parsed = parser.parse(colored)
+
+    expect(parsed).to eq([
+      {text: "foo", foreground: :yellow, background: :on_red},
+      {text: "bar", foreground: :green, style: :bold, background: :on_cyan},
+      {text: "baz", foreground: :yellow, background: :on_red}
+    ])
+  end
+
+  it "parses colors nested with blocks" do
+   pastel = Pastel.new
+   colored = pastel.red.on_green("foo") do
+               green.on_red("bar ", "baz") do
+                 yellow("qux")
+               end
+             end
+
+    parsed = parser.parse(colored)
+    expect(parsed).to eq([
+      {text: "foo", foreground: :red, background: :on_green},
+      {text: "bar baz", foreground: :green, background: :on_red},
+      {text: "qux", foreground: :yellow, background: :on_red}
+    ])
+  end
 end