(#6770) Add support for version :latest.

Specifying a version of `:latest` will find the most recent version of the
named interface installed in your RUBYLIB, and attempt to load that.  This is
unlikely to provide a stable dependency in the future, so should be used
sparingly, acknowledging the dangers.

Reviewed-By: Daniel Pittman

1 files changed, 13 insertions, 2 deletions

diff --git a/lib/puppet/interface/interface_collection.rb b/lib/puppet/interface/interface_collection.rb
index 115892397..92e2933fe 100644
--- a/lib/puppet/interface/interface_collection.rb
+++ b/lib/puppet/interface/interface_collection.rb
@@ -33,7 +33,7 @@ module Puppet::Interface::InterfaceCollection
       v_dir = File.join dir, %w[puppet interface v*]
       Dir.glob(File.join v_dir, "#{name}{.rb,/*.rb}").each do |f|
         v = f.sub(%r[.*/v([^/]+?)/#{name}(?:(?:/[^/]+)?.rb)$], '\1')
-        if v =~ SEMVER_VERSION
+        if validate_version(v)
           versions << v
         else
           warn "'#{v}' (#{f}) is not a valid version string; skipping"
@@ -43,6 +43,10 @@ module Puppet::Interface::InterfaceCollection
     return versions.uniq.sort { |a, b| compare_versions(a, b)  }
   end
 
+  def self.validate_version(version)
+    !!(SEMVER_VERSION =~ version.to_s)
+  end
+
   def self.compare_versions(a, b)
     a, b = [a, b].map do |x|
       parts = SEMVER_VERSION.match(x).to_a[1..4]
@@ -60,11 +64,18 @@ module Puppet::Interface::InterfaceCollection
   end
 
   def self.[](name, version)
-    @interfaces[underscorize(name)][version] if interface?(name, version)
+    version = versions(name).last if version == :latest
+    unless version.nil?
+      @interfaces[underscorize(name)][version] if interface?(name, version)
+    end
   end
 
   def self.interface?(name, version)
+    version = versions(name).last if version == :latest
+    return false if version.nil?
+
     name = underscorize(name)
+
     unless @interfaces.has_key?(name) && @interfaces[name].has_key?(version)
       require "puppet/interface/v#{version}/#{name}"
     end