From c301c45be21887b07288b3d91bfeec5c8df052d7 Mon Sep 17 00:00:00 2001
From: amihaiemil <amihaiemil@gmail.com>
Date: Tue, 28 Apr 2020 16:58:42 +0300
Subject: [PATCH] #14 skip() doesn't mutate the instance

---
 lib/fromarray.rb       | 4 ++--
 test/fromarray_test.rb | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/fromarray.rb b/lib/fromarray.rb
index 81c931f..fab13da 100644
--- a/lib/fromarray.rb
+++ b/lib/fromarray.rb
@@ -24,6 +24,7 @@
 
 module Stream
   # A stream implemented based on an Array.
+  # This class is immutable and thread-safe.
   # Author:: Mihai Andronache (amihaiemil@gmail.com)
   class FromArray
     def initialize(array)
@@ -38,8 +39,7 @@ def skip(count)
       @array.each_with_index do |val, index|
         skipped.push(val) unless index + 1 <= count
       end
-      @array = skipped
-      self
+      FromArray.new(skipped)
     end
 
     # Collect the stream's data into an array and return it.
diff --git a/test/fromarray_test.rb b/test/fromarray_test.rb
index b96cd06..5be1fd4 100644
--- a/test/fromarray_test.rb
+++ b/test/fromarray_test.rb
@@ -68,8 +68,8 @@ def test_skip_argument_error_count_negative
     def test_skip_returns_self
       stream = FromArray.new([1, 2, 3])
       assert(
-        stream.skip(1).equal?(stream),
-        'Method skip should return the modified stream'
+        !stream.skip(1).equal?(stream),
+        'Method skip should return a new instance of the modified stream'
       )
     end