diff --git a/lib/linguist/memory_blob.rb b/lib/linguist/memory_blob.rb
new file mode 100644
index 00000000..c17cf3e2
--- /dev/null
+++ b/lib/linguist/memory_blob.rb
@@ -0,0 +1,73 @@
+require 'linguist/blob_helper'
+
+module Linguist
+  # A MemoryBlob is a wrapper around the content of a file to make it quack
+  # like a Grit::Blob. It provides the basic interface: `name`,
+  # `data`, `path` and `size`.
+  class MemoryBlob
+    include BlobHelper
+
+    # Public: Initialize a new MemoryBlob.
+    #
+    # path    - A path String (does not necessarily exists on the file system).
+    # content - Content of the file.
+    #
+    # Returns a FileBlob.
+    def initialize(path, content)
+      @path = path
+      @content = content
+    end
+
+    # Public: Filename
+    #
+    # Examples
+    #
+    #   MemoryBlob.new("/path/to/linguist/lib/linguist.rb", "").path
+    #   # =>  "/path/to/linguist/lib/linguist.rb"
+    #
+    # Returns a String
+    attr_reader :path
+
+    # Public: File name
+    #
+    # Returns a String
+    def name
+      File.basename(@path)
+    end
+
+    # Public: File contents.
+    #
+    # Returns a String.
+    def data
+      @content
+    end
+
+    # Public: Get byte size
+    #
+    # Returns an Integer.
+    def size
+      @content.bytesize
+    end
+
+    # Public: Get file extension.
+    #
+    # Returns a String.
+    def extension
+      extensions.last || ""
+    end
+
+    # Public: Return an array of the file extensions
+    #
+    #     >> Linguist::FileBlob.new("app/views/things/index.html.erb").extensions
+    #     => [".html.erb", ".erb"]
+    #
+    # Returns an Array
+    def extensions
+      basename, *segments = name.downcase.split(".")
+
+      segments.map.with_index do |segment, index|
+        "." + segments[index..-1].join(".")
+      end
+    end
+  end
+end
diff --git a/test/helper.rb b/test/helper.rb
index ab3cc8fa..71594416 100644
--- a/test/helper.rb
+++ b/test/helper.rb
@@ -3,14 +3,21 @@ require "minitest/autorun"
 require "mocha/setup"
 require "linguist"
 require 'color-proximity'
+require "linguist/memory_blob"
 
 def fixtures_path
   File.expand_path("../fixtures", __FILE__)
 end
 
 def fixture_blob(name)
-  name = File.join(fixtures_path, name) unless name =~ /^\//
-  Linguist::FileBlob.new(name, fixtures_path)
+  filepath = (name =~ /^\//)? name : File.join(fixtures_path, name)
+  Linguist::FileBlob.new(filepath, fixtures_path)
+end
+
+def fixture_blob_memory(name)
+  filepath = (name =~ /^\//)? name : File.join(fixtures_path, name)
+  content = File.read(filepath)
+  Linguist::MemoryBlob.new(name, content)
 end
 
 def samples_path
@@ -18,6 +25,12 @@ def samples_path
 end
 
 def sample_blob(name)
-  name = File.join(samples_path, name) unless name =~ /^\//
-  Linguist::FileBlob.new(name, samples_path)
+  filepath = (name =~ /^\//)? name : File.join(samples_path, name)
+  Linguist::FileBlob.new(filepath, samples_path)
+end
+
+def sample_blob_memory(name)
+  filepath = (name =~ /^\//)? name : File.join(samples_path, name)
+  content = File.read(filepath)
+  Linguist::MemoryBlob.new(name, content)
 end
diff --git a/test/test_memory_blob.rb b/test/test_memory_blob.rb
new file mode 100644
index 00000000..1ba856de
--- /dev/null
+++ b/test/test_memory_blob.rb
@@ -0,0 +1,290 @@
+require_relative "./helper"
+
+class TestBlob < Minitest::Test
+  include Linguist
+
+  def setup
+    # git blobs are normally loaded as ASCII-8BIT since they may contain data
+    # with arbitrary encoding not known ahead of time
+    @original_external = Encoding.default_external
+    Encoding.default_external = Encoding.find("ASCII-8BIT")
+  end
+
+  def teardown
+    Encoding.default_external = @original_external
+  end
+
+  def script_blob(name)
+    blob = sample_blob_memory(name)
+    blob.instance_variable_set(:@name, 'script')
+    blob
+  end
+
+  def test_name
+    assert_equal "foo.rb", sample_blob_memory("Ruby/foo.rb").name
+  end
+
+  def test_mime_type
+    assert_equal "application/postscript", fixture_blob_memory("Binary/octocat.ai").mime_type
+    assert_equal "application/x-ruby", sample_blob_memory("Ruby/grit.rb").mime_type
+    assert_equal "application/x-sh", sample_blob_memory("Shell/script.sh").mime_type
+    assert_equal "text/plain", fixture_blob_memory("Data/README").mime_type
+  end
+
+  def test_content_type
+    assert_equal "application/pdf", fixture_blob_memory("Binary/foo.pdf").content_type
+    assert_equal "image/png", fixture_blob_memory("Binary/foo.png").content_type
+    assert_equal "text/plain; charset=iso-8859-2", fixture_blob_memory("Data/README").content_type
+  end
+
+  def test_disposition
+    assert_equal "attachment; filename=foo+bar.jar", fixture_blob_memory("Binary/foo bar.jar").disposition
+    assert_equal "attachment; filename=foo.bin", fixture_blob_memory("Binary/foo.bin").disposition
+    assert_equal "attachment; filename=linguist.gem", fixture_blob_memory("Binary/linguist.gem").disposition
+    assert_equal "attachment; filename=octocat.ai", fixture_blob_memory("Binary/octocat.ai").disposition
+    assert_equal "inline", fixture_blob_memory("Data/README").disposition
+    assert_equal "inline", sample_blob_memory("Text/foo.txt").disposition
+    assert_equal "inline", sample_blob_memory("Ruby/grit.rb").disposition
+    assert_equal "inline", fixture_blob_memory("Binary/octocat.png").disposition
+  end
+
+  def test_data
+    assert_equal "module Foo\nend\n", sample_blob_memory("Ruby/foo.rb").data
+  end
+
+  def test_lines
+    assert_equal ["module Foo", "end", ""], sample_blob_memory("Ruby/foo.rb").lines
+    assert_equal ["line 1", "line 2", ""], sample_blob_memory("Text/mac.txt").lines
+    assert_equal 475, sample_blob_memory("Emacs Lisp/ess-julia.el").lines.length
+  end
+
+  def test_lines_maintains_original_encoding
+    # Even if the file's encoding is detected as something like UTF-16LE,
+    # earlier versions of the gem made implicit guarantees that the encoding of
+    # each `line` is in the same encoding as the file was originally read (in
+    # practice, UTF-8 or ASCII-8BIT)
+    assert_equal Encoding.default_external, fixture_blob_memory("Data/utf16le").lines.first.encoding
+  end
+
+  def test_size
+    assert_equal 15, sample_blob_memory("Ruby/foo.rb").size
+  end
+
+  def test_loc
+    assert_equal 3, sample_blob_memory("Ruby/foo.rb").loc
+  end
+
+  def test_sloc
+    assert_equal 2, sample_blob_memory("Ruby/foo.rb").sloc
+    assert_equal 3, fixture_blob_memory("Data/utf16le-windows").sloc
+    assert_equal 1, fixture_blob_memory("Data/iso8859-8-i").sloc
+  end
+
+  def test_encoding
+    assert_equal "ISO-8859-2", fixture_blob_memory("Data/README").encoding
+    assert_equal "ISO-8859-2", fixture_blob_memory("Data/README").ruby_encoding
+    assert_equal "UTF-8", sample_blob_memory("Text/foo.txt").encoding
+    assert_equal "UTF-8", sample_blob_memory("Text/foo.txt").ruby_encoding
+    assert_equal "UTF-16LE", fixture_blob_memory("Data/utf16le").encoding
+    assert_equal "UTF-16LE", fixture_blob_memory("Data/utf16le").ruby_encoding
+    assert_equal "UTF-16LE", fixture_blob_memory("Data/utf16le-windows").encoding
+    assert_equal "UTF-16LE", fixture_blob_memory("Data/utf16le-windows").ruby_encoding
+    assert_equal "ISO-2022-KR", sample_blob_memory("Text/ISO-2022-KR.txt").encoding
+    assert_equal "binary", sample_blob_memory("Text/ISO-2022-KR.txt").ruby_encoding
+    assert_nil fixture_blob_memory("Binary/dog.o").encoding
+  end
+
+  def test_binary
+    assert fixture_blob_memory("Binary/git.deb").binary?
+    assert fixture_blob_memory("Binary/hello.pbc").binary?
+    assert fixture_blob_memory("Binary/linguist.gem").binary?
+    assert fixture_blob_memory("Binary/octocat.ai").binary?
+    assert fixture_blob_memory("Binary/octocat.png").binary?
+    assert fixture_blob_memory("Binary/zip").binary?
+    assert !fixture_blob_memory("Data/README").binary?
+    assert !sample_blob_memory("Ruby/foo.rb").binary?
+    assert !sample_blob_memory("Perl/script.pl").binary?
+  end
+
+  def test_all_binary
+    Samples.each do |sample|
+      blob = sample_blob_memory(sample[:path])
+      assert ! (blob.likely_binary? || blob.binary?), "#{sample[:path]} is a binary file"
+    end
+  end
+
+  def test_text
+    assert fixture_blob_memory("Data/README").text?
+    assert fixture_blob_memory("Data/md").text?
+    assert sample_blob_memory("Shell/script.sh").text?
+    assert fixture_blob_memory("Data/txt").text?
+  end
+
+  def test_image
+    assert fixture_blob_memory("Binary/octocat.png").image?
+    assert !fixture_blob_memory("Binary/octocat.ai").image?
+    assert !fixture_blob_memory("Binary/octocat.psd").image?
+  end
+
+  def test_solid
+    assert fixture_blob_memory("Binary/cube.stl").solid?
+    assert fixture_blob_memory("Data/cube.stl").solid?
+  end
+
+  def test_csv
+    assert fixture_blob_memory("Data/cars.csv").csv?
+  end
+
+  def test_pdf
+    assert fixture_blob_memory("Binary/foo.pdf").pdf?
+  end
+
+  def test_viewable
+    assert fixture_blob_memory("Data/README").viewable?
+    assert sample_blob_memory("Ruby/foo.rb").viewable?
+    assert sample_blob_memory("Perl/script.pl").viewable?
+    assert !fixture_blob_memory("Binary/linguist.gem").viewable?
+    assert !fixture_blob_memory("Binary/octocat.ai").viewable?
+    assert !fixture_blob_memory("Binary/octocat.png").viewable?
+  end
+
+  def test_generated
+    assert !fixture_blob_memory("Data/README").generated?
+
+    # Generated .NET Docfiles
+    assert sample_blob_memory("XML/net_docfile.xml").generated?
+
+    # Long line
+    assert !sample_blob_memory("JavaScript/uglify.js").generated?
+
+    # Inlined JS, but mostly code
+    assert !sample_blob_memory("JavaScript/json2_backbone.js").generated?
+
+    # Minified JS
+    assert !sample_blob_memory("JavaScript/jquery-1.6.1.js").generated?
+    assert sample_blob_memory("JavaScript/jquery-1.6.1.min.js").generated?
+    assert sample_blob_memory("JavaScript/jquery-1.4.2.min.js").generated?
+
+    # Composer generated composer.lock file
+    assert sample_blob_memory("JSON/composer.lock").generated?
+
+    # PEG.js-generated parsers
+    assert sample_blob_memory("JavaScript/parser.js").generated?
+
+    # Generated PostScript
+    assert !sample_blob_memory("PostScript/sierpinski.ps").generated?
+
+    # These examples are too basic to tell
+    assert !sample_blob_memory("JavaScript/hello.js").generated?
+
+    assert sample_blob_memory("JavaScript/intro-old.js").generated?
+    assert sample_blob_memory("JavaScript/classes-old.js").generated?
+
+    assert sample_blob_memory("JavaScript/intro.js").generated?
+    assert sample_blob_memory("JavaScript/classes.js").generated?
+
+    # Protocol Buffer generated code
+    assert sample_blob_memory("C++/protocol-buffer.pb.h").generated?
+    assert sample_blob_memory("C++/protocol-buffer.pb.cc").generated?
+    assert sample_blob_memory("Java/ProtocolBuffer.java").generated?
+    assert sample_blob_memory("Python/protocol_buffer_pb2.py").generated?
+    assert sample_blob_memory("Go/api.pb.go").generated?
+    assert sample_blob_memory("Go/embedded.go").generated?
+
+    # Apache Thrift generated code
+    assert sample_blob_memory("Python/gen-py-linguist-thrift.py").generated?
+    assert sample_blob_memory("Go/gen-go-linguist-thrift.go").generated?
+    assert sample_blob_memory("Java/gen-java-linguist-thrift.java").generated?
+    assert sample_blob_memory("JavaScript/gen-js-linguist-thrift.js").generated?
+    assert sample_blob_memory("Ruby/gen-rb-linguist-thrift.rb").generated?
+    assert sample_blob_memory("Objective-C/gen-cocoa-linguist-thrift.m").generated?
+
+    # Generated JNI
+    assert sample_blob_memory("C/jni_layer.h").generated?
+
+    # Minified CSS
+    assert !sample_blob_memory("CSS/bootstrap.css").generated?
+    assert sample_blob_memory("CSS/bootstrap.min.css").generated?
+
+    # Generated VCR
+    assert sample_blob_memory("YAML/vcr_cassette.yml").generated?
+
+    # Generated by Zephir
+    assert !sample_blob_memory("Zephir/Router.zep").generated?
+
+    # Cython-generated C/C++
+    assert sample_blob_memory("C/sgd_fast.c").generated?
+    assert sample_blob_memory("C++/wrapper_inner.cpp").generated?
+
+    # Unity3D-generated metadata
+    assert sample_blob_memory("Unity3D Asset/Tiles.meta").generated?
+  end
+
+  def test_vendored
+    assert !fixture_blob_memory("Data/README").vendored?
+  end
+
+  def test_language
+    Samples.each do |sample|
+      blob = sample_blob_memory(sample[:path])
+      assert blob.language, "No language for #{sample[:path]}"
+      assert_equal sample[:language], blob.language.name, blob.name
+    end
+
+    # Test language detection for files which shouldn't be used as samples
+    root = File.expand_path('../fixtures', __FILE__)
+    Dir.entries(root).each do |language|
+      next if language == '.' || language == '..' || language == 'Binary' ||
+              File.basename(language) == 'ace_modes.json'
+
+      # Each directory contains test files of a language
+      dirname = File.join(root, language)
+      Dir.entries(dirname).each do |filename|
+        # By default blob search the file in the samples;
+        # thus, we need to give it the absolute path
+        filepath = File.join(dirname, filename)
+        next unless File.file?(filepath)
+
+        blob = fixture_blob_memory(filepath)
+        if language == 'Data'
+          assert blob.language.nil?, "A language was found for #{filepath}"
+        elsif language == 'Generated'
+          assert blob.generated?, "#{filepath} is not a generated file"
+        else
+          assert blob.language, "No language for #{filepath}"
+          assert_equal language, blob.language.name, blob.name
+        end
+      end
+    end
+  end
+
+  def test_minified_files_not_safe_to_highlight
+    assert !sample_blob_memory("JavaScript/jquery-1.6.1.min.js").safe_to_colorize?
+  end
+
+  def test_empty
+    blob = Struct.new(:data) { include Linguist::BlobHelper }
+
+    assert blob.new("").empty?
+    assert blob.new(nil).empty?
+    refute blob.new(" ").empty?
+    refute blob.new("nope").empty?
+  end
+
+  def test_include_in_language_stats
+    generated = sample_blob_memory("CSS/bootstrap.min.css")
+    assert_predicate generated, :generated?
+    refute_predicate generated, :include_in_language_stats?
+
+    data = sample_blob_memory("Ant Build System/filenames/ant.xml")
+    assert_equal :data, data.language.type
+    refute_predicate data, :include_in_language_stats?
+
+    prose = sample_blob_memory("Markdown/tender.md")
+    assert_equal :prose, prose.language.type
+    refute_predicate prose, :include_in_language_stats?
+
+    included = sample_blob_memory("HTML/pages.html")
+    assert_predicate included, :include_in_language_stats?
+  end
+end