Add Version::NULL singleton

1 files changed, 38 insertions, 0 deletions

diff --git a/Library/Homebrew/version/null.rb b/Library/Homebrew/version/null.rb
new file mode 100644
index 000000000..77106bcce
--- /dev/null
+++ b/Library/Homebrew/version/null.rb
@@ -0,0 +1,38 @@
+class Version
+  NULL = Class.new do
+    include Comparable
+
+    def <=>(_other)
+      -1
+    end
+
+    def eql?(_other)
+      # Makes sure that the same instance of Version::NULL
+      # will never equal itself; normally Comparable#==
+      # will return true for this regardless of the return
+      # value of #<=>
+      false
+    end
+
+    def detected_from_url?
+      false
+    end
+
+    def head?
+      false
+    end
+
+    def null?
+      true
+    end
+
+    def to_f
+      Float::NAN
+    end
+
+    def to_s
+      ""
+    end
+    alias_method :to_str, :to_s
+  end.new
+end