lib/metaheader.rb in metaheader-1.1.1 vs lib/metaheader.rb in metaheader-1.2

@@ -26,14 +26,15 @@
     def parse(raw_input)
       raise NotImplementedError
     end
   end
 
-  REQUIRED = Object.new.freeze
+  BOOLEAN = Object.new.freeze
   OPTIONAL = Object.new.freeze
-  VALUE = Object.new.freeze
+  REQUIRED = Object.new.freeze
   SINGLELINE = Object.new.freeze
+  VALUE = Object.new.freeze
 
   # Whether to fail validation if unknown tags are encoutered.
   # @see #validate
   # @return [Boolean]
   attr_accessor :strict
@@ -69,19 +70,27 @@
       parser.parse input
     }
   end
 
   # Returns the value of a tag by its name, or nil if not found.
+  # @param key [Symbol] tag name
+  # @param default [Object] value to return if key doesn't exist
   # @return [Object, nil]
-  def [](key)
-    tag = @data[key] and tag.value
+  def [](key, default = nil)
+    if tag = @data[key]
+      tag.value
+    else
+      default
+    end
   end
 
   # Replaces the value of a tag.
   # @param value the new value
   # @return value
   def []=(key, value)
+    raise ArgumentError, 'value cannot be nil' if value.nil?
+
     @data[key] ||= Tag.new key
     @data[key].value = value
   end
 
   # Returns how many tags were found in the input.
@@ -94,14 +103,27 @@
   # @return [Boolean]
   def empty?
     @data.empty?
   end
 
+  # Whether a tag was found in the input.
+  # @param tag [Symbol] the tag to lookup
+  # @return [Boolean]
+  def has?(tag)
+    @data.has_key? tag.to_sym
+  end
+
+  # Removes a given tag from the list.
+  # @param tag [Symbol] the tag to remove
+  def delete(tag)
+    @data.delete tag
+  end
+
   # Make a hash from the parsed data
   # @return [Hash]
   def to_h
-    Hash[@data.map {|v| [v.first, v.last.value] }]
+    Hash[@data.map {|name, tag| [name, tag.value] }]
   end
 
   # Makes a human-readable representation of the current instance.
   # @return [String]
   def inspect
@@ -114,14 +136,15 @@
   #   mh.validate \
   #     hello: [MetaHeader::REQUIRED, MetaHeader::SINGLELINE, /\d/],
   #     chunky: proc {|value| 'not bacon' unless value == 'bacon' }
   # @param rules [Hash] tag_name => rule or array_of_rules
   # @return [Array, nil] error list or nil
-  # @see REQUIRED
+  # @see BOOLEAN
   # @see OPTIONAL
-  # @see VALUE
+  # @see REQUIRED
   # @see SINGLELINE
+  # @see VALUE
   def validate(rules)
     errors = Array.new
 
     if @strict
       @data.each_key {|key|
@@ -146,10 +169,12 @@
     (?:@(?<key>\w+)|(?<key>[\w][\w\s]*?)\s*:)
     (?:\s+(?<value>[^\n]+))?
     \Z/x.freeze
 
   def parse(line)
+    line.rstrip!
+
     # multiline value must have the same prefix
     if @last_key && line.index(@last_prefix) == 0
       # remove the line prefix
       mline = line[@last_prefix.size..-1]
       stripped = mline.strip
@@ -157,16 +182,12 @@
       indent_level = mline.index stripped
 
       if indent_level > 0
         tag = @data[@last_key]
 
-        if tag.value.is_a? String
-          tag.value += "\n"
-        else
-          tag.value = String.new
-        end
-
+        tag.value = @raw_value.to_s unless tag.value.is_a? String
+        tag.value += "\n" unless tag.value.empty?
         tag.value += stripped
 
         return
       else
         @last_key = nil
@@ -175,17 +196,34 @@
 
     return unless match = REGEX.match(line)
 
     # single line
     @last_prefix = match[:prefix]
-    @last_key = match[:key].downcase.gsub(/[^\w]/, '_').to_sym
+    key = match[:key].downcase.gsub(/[^\w]/, '_')
 
-    value = match[:value] || true
+    @raw_value = match[:value]
+    key, value = parse_value key, @raw_value
+
+    @last_key = key.to_sym
     @data[@last_key] = Tag.new match[:key].freeze, value
   end
 
+  def parse_value(key, value)
+    value ||= true
 
+    case value
+    when 'true'
+      value = true
+    when 'false'
+      value = false
+    when String
+      value = nil if value.empty?
+    end
+
+    [key, value]
+  end
+
   def validate_key(key, rules)
     rules = Array(rules)
     return if rules.empty?
 
     unless @data.has_key? key
@@ -210,19 +248,23 @@
         end
       when VALUE
         if str_value.empty?
           return "missing value for tag '%s'" % tag.name
         end
+      when BOOLEAN
+        unless [TrueClass, FalseClass].include? tag.value.class
+          return "tag '%s' cannot have a value" % tag.name
+        end
       when Regexp
         unless rule.match str_value
           return "invalid value for tag '%s'" % tag.name
         end
       when Proc, Method
         if error = rule.call(tag.value)
           return "invalid value for tag '%s': %s" % [tag.name, error]
         end
       else
-        raise ArgumentError
+        raise ArgumentError, "unsupported validator #{rule}"
       end
     }
 
     nil
   end