(#6770) Add version lookup and comparison.

Reviewed-By: Jacob Helwig

1 files changed, 35 insertions, 0 deletions

diff --git a/lib/puppet/interface/interface_collection.rb b/lib/puppet/interface/interface_collection.rb
index 51b7534a0..115892397 100644
--- a/lib/puppet/interface/interface_collection.rb
+++ b/lib/puppet/interface/interface_collection.rb
@@ -1,6 +1,8 @@
 require 'puppet/interface'
 
 module Puppet::Interface::InterfaceCollection
+  SEMVER_VERSION = /^(\d+)\.(\d+)\.(\d+)([A-Za-z][0-9A-Za-z-]*|)$/
+
   @interfaces = Hash.new { |hash, key| hash[key] = {} }
 
   def self.interfaces
@@ -24,6 +26,39 @@ module Puppet::Interface::InterfaceCollection
     return @interfaces.keys
   end
 
+  def self.versions(name)
+    versions = []
+    $LOAD_PATH.each do |dir|
+      next unless FileTest.directory?(dir)
+      v_dir = File.join dir, %w[puppet interface v*]
+      Dir.glob(File.join v_dir, "#{name}{.rb,/*.rb}").each do |f|
+        v = f.sub(%r[.*/v([^/]+?)/#{name}(?:(?:/[^/]+)?.rb)$], '\1')
+        if v =~ SEMVER_VERSION
+          versions << v
+        else
+          warn "'#{v}' (#{f}) is not a valid version string; skipping"
+        end
+      end
+    end
+    return versions.uniq.sort { |a, b| compare_versions(a, b)  }
+  end
+
+  def self.compare_versions(a, b)
+    a, b = [a, b].map do |x|
+      parts = SEMVER_VERSION.match(x).to_a[1..4]
+      parts[0..2] = parts[0..2].map { |e| e.to_i }
+      parts
+    end
+
+    cmp = a[0..2] <=> b[0..2]
+    if cmp == 0
+      cmp = a[3] <=> b[3]
+      cmp = +1 if a[3].empty? && !b[3].empty?
+      cmp = -1 if b[3].empty? && !a[3].empty?
+    end
+    cmp
+  end
+
   def self.[](name, version)
     @interfaces[underscorize(name)][version] if interface?(name, version)
   end