Fix sort testcase input sorted unintentionally

sorts/sorts_test.go

@@ -7,7 +7,7 @@ import (
 func testFramework(t *testing.T, sortingFunction func([]int) []int) {
 	for _, test := range sortTests {
 		t.Run(test.name, func(t *testing.T) {
-			actual := sortingFunction(test.input)
+			actual := sortingFunction(cloneIntSlice(test.input))
 			pos, sorted := compareSlices(actual, test.expected)
 			if !sorted {
 				if pos == -1 {
@@ -60,69 +60,42 @@ func TestSelection(t *testing.T) {
 
 //END TESTS
 
-func BenchmarkBubble(b *testing.B) {
+func benchmarkFramework(b *testing.B, sortingFunction func([]int) []int) {
 	for i := 0; i < b.N; i++ {
 		for _, test := range sortTests {
-			bubbleSort(test.input)
+			b.StopTimer()
+			input := cloneIntSlice(test.input)
+			b.StartTimer()
+			sortingFunction(input)
 		}
 	}
 }
 
+func BenchmarkBubble(b *testing.B) {
+	benchmarkFramework(b, bubbleSort)
+}
 func BenchmarkInsertion(b *testing.B) {
-	for i := 0; i < b.N; i++ {
-		for _, test := range sortTests {
-			InsertionSort(test.input)
-		}
-	}
+	benchmarkFramework(b, InsertionSort)
 }
-
 func BenchmarkMerge(b *testing.B) {
-	for i := 0; i < b.N; i++ {
-		for _, test := range sortTests {
-			Mergesort(test.input)
-		}
-	}
+	benchmarkFramework(b, Mergesort)
 }
-
 func BenchmarkHeap(b *testing.B) {
-	for i := 0; i < b.N; i++ {
-		for _, test := range sortTests {
-			HeapSort(test.input)
-		}
-	}
+	benchmarkFramework(b, HeapSort)
 }
-
 func BenchmarkQuick(b *testing.B) {
-	for i := 0; i < b.N; i++ {
-		for _, test := range sortTests {
-			QuickSort(test.input)
-		}
-	}
+	benchmarkFramework(b, QuickSort)
 }
-
 func BenchmarkShell(b *testing.B) {
-	for i := 0; i < b.N; i++ {
-		for _, test := range sortTests {
-			ShellSort(test.input)
-		}
-	}
+	benchmarkFramework(b, ShellSort)
 }
-
 func BenchmarkRadix(b *testing.B) {
-	for i := 0; i < b.N; i++ {
-		for _, test := range sortTests {
-			RadixSort(test.input)
-		}
-	}
+	benchmarkFramework(b, RadixSort)
 }
 
 // Very Slow, consider commenting
 func BenchmarkSelection(b *testing.B) {
-	for i := 0; i < b.N; i++ {
-		for _, test := range sortTests {
-			SelectionSort(test.input)
-		}
-	}
+	benchmarkFramework(b, SelectionSort)
 }
 
 func compareSlices(a []int, b []int) (int, bool) {

sorts/sorts_testcases.go

@@ -70,6 +70,13 @@ func makeRandomSignedSlice(size int) []int {
 }
 
 func getSortedVersion(a []int) []int {
-	sort.Slice(a, func(i, j int) bool { return a[i] < a[j] })
-	return a
+	b := cloneIntSlice(a)
+	sort.Slice(b, func(i, j int) bool { return b[i] < b[j] })
+	return b
+}
+
+func cloneIntSlice(src []int) []int {
+	vals := make([]int, len(src))
+	copy(vals, src)
+	return vals
 }