From 45fd4e4ff16dd63d60afe816c41ee71e1a16db28 Mon Sep 17 00:00:00 2001
From: Evgenii Stratonikov <e.stratonikov@yadro.com>
Date: Thu, 8 Feb 2024 19:14:34 +0300
Subject: [PATCH] [#972] pilorama: Remove removeDuplicatesInPlace()

Also, check that slices.CompareFunc() indeed passes all the tests before
removal.

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
---
 pkg/local_object_storage/pilorama/batch.go    | 15 +---
 .../pilorama/batch_test.go                    | 70 -------------------
 2 files changed, 2 insertions(+), 83 deletions(-)
 delete mode 100644 pkg/local_object_storage/pilorama/batch_test.go

diff --git a/pkg/local_object_storage/pilorama/batch.go b/pkg/local_object_storage/pilorama/batch.go
index c65488b74..520c6dfb4 100644
--- a/pkg/local_object_storage/pilorama/batch.go
+++ b/pkg/local_object_storage/pilorama/batch.go
@@ -2,6 +2,7 @@ package pilorama
 
 import (
 	"encoding/binary"
+	"slices"
 	"sort"
 	"sync"
 	"time"
@@ -50,7 +51,7 @@ func (b *batch) run() {
 		sort.Slice(b.operations, func(i, j int) bool {
 			return b.operations[i].Time < b.operations[j].Time
 		})
-		b.operations = removeDuplicatesInPlace(b.operations)
+		b.operations = slices.CompactFunc(b.operations, func(x, y *Move) bool { return x.Time == y.Time })
 
 		// Our main use-case is addition of new items. In this case,
 		// we do not need to perform undo()/redo(), just do().
@@ -115,15 +116,3 @@ func (b *batch) run() {
 		b.results[i] <- err
 	}
 }
-
-func removeDuplicatesInPlace(a []*Move) []*Move {
-	equalCount := 0
-	for i := 1; i < len(a); i++ {
-		if a[i].Time == a[i-1].Time {
-			equalCount++
-		} else {
-			a[i-equalCount] = a[i]
-		}
-	}
-	return a[:len(a)-equalCount]
-}
diff --git a/pkg/local_object_storage/pilorama/batch_test.go b/pkg/local_object_storage/pilorama/batch_test.go
deleted file mode 100644
index 931fce18c..000000000
--- a/pkg/local_object_storage/pilorama/batch_test.go
+++ /dev/null
@@ -1,70 +0,0 @@
-package pilorama
-
-import (
-	"testing"
-
-	"github.com/stretchr/testify/require"
-)
-
-func Test_removeDuplicatesInPlace(t *testing.T) {
-	testCases := []struct {
-		before []int
-		after  []int
-	}{
-		{
-			before: []int{},
-			after:  []int{},
-		},
-		{
-			before: []int{1},
-			after:  []int{1},
-		},
-		{
-			before: []int{1, 2},
-			after:  []int{1, 2},
-		},
-		{
-			before: []int{1, 2, 3},
-			after:  []int{1, 2, 3},
-		},
-		{
-			before: []int{1, 1, 2},
-			after:  []int{1, 2},
-		},
-		{
-			before: []int{1, 2, 2},
-			after:  []int{1, 2},
-		},
-		{
-			before: []int{1, 2, 2, 3},
-			after:  []int{1, 2, 3},
-		},
-		{
-			before: []int{1, 1, 1},
-			after:  []int{1},
-		},
-		{
-			before: []int{1, 1, 2, 2},
-			after:  []int{1, 2},
-		},
-		{
-			before: []int{1, 1, 1, 2, 3, 3, 3},
-			after:  []int{1, 2, 3},
-		},
-	}
-
-	for _, tc := range testCases {
-		ops := make([]*Move, len(tc.before))
-		for i := range ops {
-			ops[i] = &Move{Meta: Meta{Time: Timestamp(tc.before[i])}}
-		}
-
-		expected := make([]*Move, len(tc.after))
-		for i := range expected {
-			expected[i] = &Move{Meta: Meta{Time: Timestamp(tc.after[i])}}
-		}
-
-		actual := removeDuplicatesInPlace(ops)
-		require.Equal(t, expected, actual, "%d", tc.before)
-	}
-}