Update demo, test, and code file with example showing how order matters.

rubyworks · Apr 19, 2015 · 62b8ca3 · 62b8ca3
1 parent 14212c7
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Showing 3 changed files with 20 additions and 2 deletions.
diff --git a/demo/core/array/uniq_by.md b/demo/core/array/uniq_by.md
@@ -2,8 +2,15 @@
 
     require 'facets/array/uniq_by'
 
-    e = [-5, -4, -3, -2, -1, 0]
+Like #uniq, but determines uniqueness based on a given block.  
+As can be seen from the examples, order is significant.
+
     r = (-5..5).to_a
     r.uniq_by!{ |i| i*i }
-    r.assert == e
+    r.assert == [-5, -4, -3, -2, -1, 0]
+
+    r = (-5..5).to_a.reverse
+    r.uniq_by!{ |i| i*i }
+    r.assert == [5, 4, 3, 2, 1, 0]
+
 
diff --git a/lib/core/facets/array/uniq_by.rb b/lib/core/facets/array/uniq_by.rb
@@ -9,6 +9,10 @@ class Array
   #   a.uniq_by!{ |i| i*i }
   #   a #=> [-5, -4, -3, -2, -1, 0]
   #
+  #   a = (-5..5).to_a.reverse
+  #   a.uniq_by!{ |i| i*i }
+  #   a #=> [5, 4, 3, 2, 1, 0]
+  #
   # Returns [Array] of unique elements.
   #
   def uniq_by! #:yield:

diff --git a/test/core/array/test_uniq_by.rb b/test/core/array/test_uniq_by.rb
@@ -11,6 +11,13 @@
       r.assert == e
     end
 
+    test do
+      e = [5, 4, 3, 2, 1, 0]
+      r = (-5..5).to_a.reverse
+      r.uniq_by!{ |i| i*i }
+      r.assert == e
+    end
+
   end
 
 end