Add mutant-minitest integration and mutation coverage tests

Author: sferik

.mutant.yml

@@ -0,0 +1,21 @@
+usage: opensource
+
+environment_variables:
+  MUTANT: "true"
+
+integration:
+  name: minitest
+
+includes:
+  - lib
+  - test
+
+requires:
+  - http/form_data
+
+mutation:
+  timeout: 10.0
+
+matcher:
+  subjects:
+    - HTTP::FormData*

Gemfile

@@ -14,6 +14,8 @@ group :test do
 
   gem "simplecov", require: false
 
+  gem "mutant-minitest"
+
   gem "yardstick"
 end
 

Rakefile

@@ -23,4 +23,9 @@ Yardstick::Rake::Verify.new do |verify|
   verify.threshold = 100
 end
 
+desc "Run mutation testing with Mutant"
+task :mutant do
+  system("bundle exec mutant run") || abort("Mutant failed!")
+end
+
 task default: %i[test rubocop verify_measurements]

lib/http/form_data.rb

@@ -63,8 +63,7 @@ def create(data, encoder: nil)
       # @raise [Error] `obj` can't be coerced
       # @return [Hash]
       def ensure_hash(obj)
-        if    obj.nil?               then {}
-        elsif obj.is_a?(Hash)        then obj
+        if    obj.is_a?(Hash)        then obj
         elsif obj.respond_to?(:to_h) then obj.to_h
         else raise Error, "#{obj.inspect} is neither Hash nor responds to :to_h"
         end
@@ -95,9 +94,7 @@ def ensure_data(obj)
       # @return [Boolean]
       def multipart?(data)
         data.any? do |_, v|
-          next true if v.is_a? FormData::Part
-
-          v.respond_to?(:to_ary) && v.to_ary.any?(FormData::Part)
+          v.is_a?(Part) || (v.respond_to?(:to_ary) && v.to_ary.any?(Part))
         end
       end
     end

lib/http/form_data/composite_io.rb

@@ -13,10 +13,9 @@ class CompositeIO
       #
       # @api public
       # @param [Array<IO>] ios Array of IO objects
-      def initialize(ios) # rubocop:disable Metrics/MethodLength
-        @index  = 0
-        @buffer = "".b
-        @ios    = ios.map do |io|
+      def initialize(ios)
+        @index = 0
+        @ios   = ios.map do |io|
           if io.is_a?(String)
             StringIO.new(io)
           elsif io.respond_to?(:read)
@@ -76,7 +75,7 @@ def rewind
       #
       # @api private
       # @return [void]
-      def read_chunks(length = nil)
+      def read_chunks(length)
         while (chunk = readpartial(length))
           yield chunk.force_encoding(Encoding::BINARY)
 
@@ -92,24 +91,16 @@ def read_chunks(length = nil)
       #
       # @api private
       # @return [String, nil]
-      def readpartial(max_length = nil)
-        while current_io
-          chunk = current_io.read(max_length, @buffer)
+      def readpartial(max_length)
+        while (io = @ios.at(@index))
+          chunk = io.read(max_length)
 
           return chunk if chunk && !chunk.empty?
 
           advance_io
         end
       end
 
-      # Returns IO object under the cursor
-      #
-      # @api private
-      # @return [IO, nil]
-      def current_io
-        @ios[@index]
-      end
-
       # Advances cursor to the next IO object
       #
       # @api private

lib/http/form_data/file.rb

@@ -46,12 +46,12 @@ class File < Part
       # @option opts [#to_s] :filename
       #   When `path_or_io` is a String, Pathname or File, defaults to basename.
       #   When `path_or_io` is a IO, defaults to `"stream-{object_id}"`
-      def initialize(path_or_io, opts = {}) # rubocop:disable Lint/MissingSuper
+      def initialize(path_or_io, opts = nil) # rubocop:disable Lint/MissingSuper
         opts = FormData.ensure_hash(opts)
 
         if opts.key? :mime_type
           warn "[DEPRECATED] :mime_type option deprecated, use :content_type"
-          opts[:content_type] = opts[:mime_type]
+          opts[:content_type] = opts.fetch(:mime_type)
         end
 
         @io           = make_io(path_or_io)
@@ -68,8 +68,8 @@ def initialize(path_or_io, opts = {}) # rubocop:disable Lint/MissingSuper
       # @return [IO]
       def make_io(path_or_io)
         if path_or_io.is_a?(String)
-          ::File.open(path_or_io, binmode: true)
-        elsif defined?(Pathname) && path_or_io.is_a?(Pathname)
+          ::File.new(path_or_io, binmode: true)
+        elsif path_or_io.is_a?(Pathname)
           path_or_io.open(binmode: true)
         else
           path_or_io
@@ -83,7 +83,7 @@ def make_io(path_or_io)
       # @return [String]
       def filename_for(io)
         if io.respond_to?(:path)
-          ::File.basename io.path
+          io.path.split(::File::SEPARATOR).last
         else
           "stream-#{io.object_id}"
         end

lib/http/form_data/multipart/param.rb

@@ -33,10 +33,10 @@ def initialize(name, value)
           @name = name.to_s
 
           @part =
-            if value.is_a?(FormData::Part)
+            if value.is_a?(Part)
               value
             else
-              FormData::Part.new(value)
+              Part.new(value)
             end
 
           @io = CompositeIO.new [header, @part, footer]
@@ -49,11 +49,10 @@ def initialize(name, value)
         # @api private
         # @return [String]
         def header
-          header = "".b
-          header << "Content-Disposition: form-data; #{parameters}#{CRLF}"
-          header << "Content-Type: #{content_type}#{CRLF}" if content_type
-          header << CRLF
-          header
+          parts = ["Content-Disposition: form-data; #{parameters}#{CRLF}"]
+          parts << "Content-Type: #{content_type}#{CRLF}" if content_type
+          parts << CRLF
+          parts.join
         end
 
         # Builds Content-Disposition parameters string
@@ -87,7 +86,7 @@ def filename
         # @api private
         # @return [String]
         def footer
-          CRLF.dup
+          "\r\n"
         end
       end
     end

lib/http/form_data/urlencoded.rb

@@ -63,7 +63,7 @@ def encoder=(implementation)
         # @see .encoder=
         # @return [#call]
         def encoder
-          @encoder ||= DefaultEncoder.method(:encode)
+          @encoder || DefaultEncoder
         end
 
         # Default encoder for urlencoded form data
@@ -90,6 +90,8 @@ def encode(value, prefix = nil)
               end
             end
 
+            alias call encode
+
             private
 
             # Encodes an Array value