From 7fb8f71653cd0c1d424138f5382e119852680f0f Mon Sep 17 00:00:00 2001
From: Maciej Ksiazek <xsms@poczta.onet.pl>
Date: Tue, 12 Apr 2011 17:18:52 +0200
Subject: [PATCH] Allowing multiple externs to be passed in options

---
 lib/closure/compiler.rb            | 8 +++++++-
 test/unit/test_closure_compiler.rb | 9 +++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/lib/closure/compiler.rb b/lib/closure/compiler.rb
index 476d9b3..5fc30c3 100644
--- a/lib/closure/compiler.rb
+++ b/lib/closure/compiler.rb
@@ -51,7 +51,13 @@ def compile(io)
 
     # Serialize hash options to the command-line format.
     def serialize_options(options)
-      options.map {|k, v| ["--#{k}", v.to_s] }.flatten
+      options.map do |k, v|
+        if (v.is_a?(Array))
+          v.map {|v2| ["--#{k}", v2.to_s]}
+        else
+          ["--#{k}", v.to_s]
+        end
+      end.flatten
     end
 
     def command
diff --git a/test/unit/test_closure_compiler.rb b/test/unit/test_closure_compiler.rb
index da518d8..dfeb471 100644
--- a/test/unit/test_closure_compiler.rb
+++ b/test/unit/test_closure_compiler.rb
@@ -60,4 +60,13 @@ def test_permissions
     assert File.executable?(COMPILER_JAR)
   end
 
+  def test_serialize_options
+    assert_equal ["--externs",  "library1.js", "--compilation_level", "ADVANCED_OPTIMIZATIONS"], Closure::Compiler.new.send(:serialize_options, 'externs' => 'library1.js', "compilation_level" => "ADVANCED_OPTIMIZATIONS")
+  end
+  
+  def test_serialize_options_for_arrays
+    compiler = Closure::Compiler.new('externs' => ['library1.js', "library2.js"])
+    assert_equal ["--externs", "library1.js", "--externs", "library2.js"], compiler.send(:serialize_options, 'externs' => ['library1.js', "library2.js"])
+  end
+
 end