From c57ab7544181c5fd62f1c93a3f5285809d95d497 Mon Sep 17 00:00:00 2001
From: Ifedapo Olarewaju <ifedapoolarewaju@gmail.com>
Date: Sun, 20 May 2018 11:55:29 +0100
Subject: [PATCH] prevent duplicate assembly steps

fixes #27
---
 CHANGELOG.md                           | 4 ++++
 lib/transloadit/assembly.rb            | 3 +++
 test/unit/test_transloadit.rb          | 4 ++--
 test/unit/transloadit/test_assembly.rb | 9 +++++++++
 4 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9622c14..c76d8f2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+### 3.0.0 / ????-??-?? ###
+
+* Prevent duplicate assembly steps [#49](https://github.com/transloadit/ruby-sdk/issues/27) (@ifedapoolarewaju)
+
 ### 2.0.1 / 2017-01-23 ###
 
 * Use the ssl enabled url as the API base url (@ifedapoolarewaju)
diff --git a/lib/transloadit/assembly.rb b/lib/transloadit/assembly.rb
index 9a7c4bf..d21c604 100644
--- a/lib/transloadit/assembly.rb
+++ b/lib/transloadit/assembly.rb
@@ -144,6 +144,9 @@ def _wrap_steps_in_hash(steps)
       when Hash               then steps
       when Transloadit::Step  then steps.to_hash
       else
+        if steps.uniq(&:name) != steps
+          raise ArgumentError, "There are different Assembly steps using the same name"
+        end
         steps.inject({}) {|h, s| h.update s }
     end
   end
diff --git a/test/unit/test_transloadit.rb b/test/unit/test_transloadit.rb
index b3189c0..543d0bc 100644
--- a/test/unit/test_transloadit.rb
+++ b/test/unit/test_transloadit.rb
@@ -75,8 +75,8 @@
 
     it 'must create assemblies with multiple steps' do
       steps = [
-        @transloadit.step(nil, nil),
-        @transloadit.step(nil, nil),
+        @transloadit.step('step1', nil),
+        @transloadit.step('step2', nil),
       ]
 
       assembly = @transloadit.assembly :steps => steps
diff --git a/test/unit/transloadit/test_assembly.rb b/test/unit/transloadit/test_assembly.rb
index efb6787..07aa9e0 100644
--- a/test/unit/transloadit/test_assembly.rb
+++ b/test/unit/transloadit/test_assembly.rb
@@ -168,6 +168,15 @@
       @assembly.to_hash[:steps].keys.must_include @encode.name
       @assembly.to_hash[:steps].keys.must_include @thumbs.name
     end
+
+    it 'must not allow duplicate steps' do
+      thumbs = @transloadit.step('thumbs', '/video/thumbs')
+      thumbs_duplicate = @transloadit.step('thumbs', '/video/encode')
+      options = { :steps => [ thumbs, thumbs_duplicate ] }
+      assert_raises ArgumentError do
+        response = @assembly.create! open('lib/transloadit/version.rb'), options
+      end
+    end
   end
 
   describe 'using assembly API methods' do