1 files changed, 56 insertions, 0 deletions
diff --git a/spec/mspec/lib/mspec/runner/actions/tagpurge.rb b/spec/mspec/lib/mspec/runner/actions/tagpurge.rb
new file mode 100644
index 0000000000..f4587de6bc
--- /dev/null
+++ b/spec/mspec/lib/mspec/runner/actions/tagpurge.rb
@@ -0,0 +1,56 @@
+require 'mspec/runner/actions/filter'
+require 'mspec/runner/actions/taglist'
+
+# TagPurgeAction - removes all tags not matching any spec
+# descriptions.
+class TagPurgeAction < TagListAction
+  attr_reader :matching
+
+  def initialize
+    @matching = []
+    @filter   = nil
+    @tags     = nil
+  end
+
+  # Prints a banner about purging tags.
+  def start
+    print "\nRemoving tags not matching any specs\n\n"
+  end
+
+  # Creates a MatchFilter for all tags.
+  def load
+    @filter = nil
+    @tags = MSpec.read_tags self
+    desc = @tags.map { |t| t.description }
+    @filter = MatchFilter.new(nil, *desc) unless desc.empty?
+  end
+
+  # Saves any matching tags
+  def after(state)
+    @matching << state.description if self === state.description
+  end
+
+  # Rewrites any matching tags. Prints non-matching tags.
+  # Deletes the tag file if there were no tags (this cleans
+  # up empty or malformed tag files).
+  def unload
+    if @filter
+      matched = @tags.select { |t| @matching.any? { |s| s == t.description } }
+      MSpec.write_tags matched
+
+      (@tags - matched).each { |t| print t.description, "\n" }
+    else
+      MSpec.delete_tags
+    end
+  end
+
+  def register
+    super
+    MSpec.register :unload, self
+  end
+
+  def unregister
+    super
+    MSpec.unregister :unload, self
+  end
+end