From a0162423df94e077ebf3efa5520403aa86f6c38c Mon Sep 17 00:00:00 2001
From: dB <dblock@dblock.org>
Date: Sat, 15 Aug 2015 16:46:54 -0400
Subject: [PATCH] WIP: always expand additional link variables, #84.

---
 .rubocop_todo.yml                      | 16 +++++++++++-----
 lib/hyperclient/link.rb                |  1 +
 lib/uri_template/rfc6570/expression.rb | 24 ++++++++++++++++++++++++
 3 files changed, 36 insertions(+), 5 deletions(-)
 create mode 100644 lib/uri_template/rfc6570/expression.rb

diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index a928c0e..8d616aa 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -1,11 +1,15 @@
 # This configuration was generated by
 # `rubocop --auto-gen-config`
-# on 2015-08-15 17:01:12 -0400 using RuboCop version 0.33.0.
+# on 2015-08-15 17:12:38 -0400 using RuboCop version 0.33.0.
 # The point is for the user to remove these configuration records
 # one by one as the offenses are removed from the code base.
 # Note that changes in the inspected code, or installation of new
 # versions of RuboCop, may require this file to be generated again.
 
+# Offense count: 1
+Metrics/AbcSize:
+  Max: 19
+
 # Offense count: 1
 # Configuration parameters: CountComments.
 Metrics/ClassLength:
@@ -16,10 +20,10 @@ Metrics/ClassLength:
 Metrics/LineLength:
   Max: 142
 
-# Offense count: 3
+# Offense count: 4
 # Configuration parameters: CountComments.
 Metrics/MethodLength:
-  Max: 14
+  Max: 16
 
 # Offense count: 3
 # Configuration parameters: CountComments.
@@ -31,14 +35,15 @@ Style/AsciiComments:
   Exclude:
     - 'lib/hyperclient/collection.rb'
 
-# Offense count: 2
+# Offense count: 3
 # Configuration parameters: EnforcedStyle, SupportedStyles.
 Style/ClassAndModuleChildren:
   Exclude:
     - 'features/steps/api_navigation.rb'
     - 'features/steps/default_config.rb'
+    - 'lib/uri_template/rfc6570/expression.rb'
 
-# Offense count: 14
+# Offense count: 15
 Style/Documentation:
   Exclude:
     - 'features/steps/api_navigation.rb'
@@ -46,6 +51,7 @@ Style/Documentation:
     - 'features/support/api.rb'
     - 'features/support/fixtures.rb'
     - 'lib/hyperclient/version.rb'
+    - 'lib/uri_template/rfc6570/expression.rb'
     - 'test/faraday/connection_test.rb'
     - 'test/hyperclient/attributes_test.rb'
     - 'test/hyperclient/collection_test.rb'
diff --git a/lib/hyperclient/link.rb b/lib/hyperclient/link.rb
index c660ed5..fa98cf8 100644
--- a/lib/hyperclient/link.rb
+++ b/lib/hyperclient/link.rb
@@ -1,6 +1,7 @@
 require 'hyperclient/resource'
 require 'uri_template'
 require 'futuroscope'
+require_relative '../uri_template/rfc6570/expression'
 
 module Hyperclient
   # Internal: The Link is used to let a Resource interact with the API.
diff --git a/lib/uri_template/rfc6570/expression.rb b/lib/uri_template/rfc6570/expression.rb
new file mode 100644
index 0000000..1e20351
--- /dev/null
+++ b/lib/uri_template/rfc6570/expression.rb
@@ -0,0 +1,24 @@
+require 'uri_template/rfc6570/expression'
+
+class URITemplate::RFC6570
+  class Expression < Token
+    def expand(vars)
+      unused_vars = vars.keys.dup
+      result = []
+      @variable_specs.each do |var, expand, max_length|
+        if Utils.def?(vars[var])
+          result.push(*expand_one(var, vars[var], expand, max_length))
+        end
+        unused_vars.delete(var)
+      end
+      unused_vars.each do |k|
+        result.push(*expand_one(k, vars[k], false, 0))
+      end
+      if result.any?
+        return (self.class::PREFIX + result.join(self.class::SEPARATOR))
+      else
+        return ''
+      end
+    end
+  end
+end