Refactor specs and merge sort code.

Author: deepakhb2

lib/Algorithm-Sorting/merge_sort.rb

@@ -1,36 +1,34 @@
 # Best case: Omega(nlog(n))
 # Worst case: O(nlog(n))
 
-values = [5,2,4,7,1,3,6]
-
-def merge(left, right)
-  result = []
-  i, j = 0, 0 
-  while(i < left.size && j < right.size)
-    if(left[i] < right[j])
-      result.push(left[i])
-      i += 1
-    else
-      result.push(right[j])
-      j += 1
+class MergeSort
+  class << self
+    def merge(left, right)
+      result = []
+      i, j = 0, 0
+      while(i < left.size && j < right.size)
+        if(left[i] < right[j])
+          result.push(left[i])
+          i += 1
+        else
+          result.push(right[j])
+          j += 1
+        end
+      end
+      return result + left[i..-1] + right[j..-1]
     end
-  end
-  return result + left[i..-1] + right[j..-1]
-end
 
-def merge_sort(arr)
-  if(arr.size == 1)
-    return arr
-  end
-  len = arr.size
-  mid = len/2
-  start = 0
+    def recursive(arr)
+      return arr if(arr.size == 1)
 
-  return merge(
-    merge_sort(arr[start...mid]),
-    merge_sort(arr[mid...len])
-  )
-end
+      len = arr.size
+      mid = len/2
+      start = 0
 
-p values
-p merge_sort(values)
+      return merge(
+        recursive(arr[start...mid]),
+        recursive(arr[mid...len])
+      )
+    end
+  end
+end

spec/Algorithm-Sorting/merge_sort_spec.rb

@@ -0,0 +1,8 @@
+require_relative './shared_example.rb'
+require_relative '../../lib/Algorithm-Sorting/merge_sort.rb'
+
+describe MergeSort do
+  let(:values) { [5,2,4,7,1,3,6] }
+
+  include_examples "recursive"
+end

spec/Algorithm-Sorting/quick_sort_spec.rb

@@ -0,0 +1,6 @@
+require_relative './shared_example.rb'
+require_relative '../../lib/Algorithm-Sorting/quick_sort.rb'
+
+describe QuickSort do
+  include_examples "sorting"
+end

spec/Algorithm-Sorting/shared_example.rb

@@ -1,15 +1,22 @@
-shared_examples "sorting" do
-  let(:values) { [5,2,4,7,1,3,6] }
-
+shared_examples "recursive" do
   describe '#recursive' do
     it 'sort using recursive technique' do
       expect(described_class.recursive(values)).to eq([1,2,3,4,5,6,7])
     end
   end
+end
 
+shared_examples "non_recursive" do
   describe '#non_recursive' do
     it 'sort using non-recursive technique' do
       expect(described_class.non_recursive(values)).to eq([1,2,3,4,5,6,7])
     end
   end
 end
+
+shared_examples "sorting" do
+  let(:values) { [5,2,4,7,1,3,6] }
+
+  include_examples "recursive"
+  include_examples "recursive"
+end