1 files changed, 39 insertions, 0 deletions
diff --git a/spec/mspec/lib/mspec/guards/version.rb b/spec/mspec/lib/mspec/guards/version.rb
new file mode 100644
index 0000000000..110853e082
--- /dev/null
+++ b/spec/mspec/lib/mspec/guards/version.rb
@@ -0,0 +1,39 @@
+require 'mspec/utils/deprecate'
+require 'mspec/utils/version'
+require 'mspec/guards/guard'
+
+class VersionGuard < SpecGuard
+  FULL_RUBY_VERSION = SpecVersion.new SpecGuard.ruby_version(:full)
+
+  def initialize(version)
+    case version
+    when String
+      @version = SpecVersion.new version
+    when Range
+      MSpec.deprecate "an empty version range end", 'a specific version' if version.end.empty?
+      a = SpecVersion.new version.begin
+      b = SpecVersion.new version.end
+      unless version.exclude_end?
+        MSpec.deprecate "ruby_version_is with an inclusive range", 'an exclusive range ("2.1"..."2.3")'
+      end
+      @version = version.exclude_end? ? a...b : a..b
+    else
+      raise "version must be a String or Range but was a #{version.class}"
+    end
+    @parameters = [version]
+  end
+
+  def match?
+    if Range === @version
+      @version.include? FULL_RUBY_VERSION
+    else
+      FULL_RUBY_VERSION >= @version
+    end
+  end
+end
+
+class Object
+  def ruby_version_is(*args, &block)
+    VersionGuard.new(*args).run_if(:ruby_version_is, &block)
+  end
+end