first post

lib/fakefs.rb

@@ -0,0 +1,163 @@
+module FakeFS
+  module FileUtils
+    extend self
+
+    def mkdir_p(path)
+      FileSystem.add(path, MockDir.new)
+    end
+
+    def rm(path)
+      FileSystem.delete(path)
+    end
+    alias_method :rm_rf, :rm
+
+    def ln_s(target, path)
+      FileSystem.add(path, MockSymlink.new(target))
+    end
+
+    def cp_r(src, dest)
+      if dir = FileSystem.find(src)
+        FileSystem.add(dest, dir.entry)
+      end
+    end
+
+    def mv(src, dest)
+      if target = FileSystem.find(src)
+        FileSystem.add(dest, target.entry)
+        FileSystem.delete(src)
+      end
+    end
+  end
+
+  class File
+    PATH_SEPARATOR = '/'
+
+    def self.join(*parts)
+      parts * PATH_SEPARATOR
+    end
+
+    def self.exists?(path)
+      FileSystem.find(path)
+    end
+
+    def self.expand_path(path)
+      ::File.expand_path(path)
+    end
+
+    def self.readlink(path)
+      symlink = FileSystem.find(path)
+      FileSystem.find(symlink.target).to_s
+    end
+  end
+
+  class Dir
+    def self.glob(pattern)
+      FileSystem.find(pattern).map { |entry| entry.to_s}
+    end
+
+    def self.[](pattern)
+      glob(pattern)
+    end
+  end
+
+  module FileSystem
+    extend self
+
+    def fs
+      @fs ||= MockDir.new('.')
+    end
+
+    def clear
+      @fs = nil
+    end
+
+    def find(path)
+      parts = path_parts(path)
+
+      target = parts[0...-1].inject(fs) do |dir, part|
+        dir[part] || {}
+      end
+
+      case parts.last
+      when '*'
+        target.values
+      else
+        target[parts.last]
+      end
+    end
+
+    def add(path, object)
+      parts = path_parts(path)
+
+      d = parts[0...-1].inject(fs) do |dir, part|
+        dir[part] ||= MockDir.new(part, dir)
+      end
+
+      object.name = parts.last
+      object.parent = d
+      d[parts.last] = object
+    end
+
+    def delete(path)
+      if dir = FileSystem.find(path)
+        dir.parent.delete(dir.name)
+      end
+    end
+
+    def path_parts(path)
+      path.split(File::PATH_SEPARATOR)
+    end
+  end
+
+  class MockDir < Hash
+    attr_accessor :name, :parent
+
+    def initialize(name = nil, parent = nil)
+      @name = name
+      @parent = parent
+    end
+
+    def entry
+      self
+    end
+
+    def to_s
+      if parent && parent.to_s != '.'
+        parent.to_s + '/' + name
+      else
+        name
+      end
+    end
+  end
+
+  class MockSymlink
+    attr_accessor :name, :target
+    alias_method  :to_s, :name
+
+    def initialize(target)
+      @target = target
+    end
+
+    def inspect
+      "symlink(#{target.split('/').last})"
+    end
+
+    def entry
+      FileSystem.find(target)
+    end
+
+    def method_missing(*args, &block)
+      entry.send(*args, &block)
+    end
+  end
+end
+
+Object.class_eval do
+  remove_const(:Dir)
+  remove_const(:File)
+  remove_const(:FileUtils)
+end
+
+File = FakeFS::File
+FileUtils = FakeFS::FileUtils
+Dir = FakeFS::Dir