bytes,strings,unicode/utf16: use slices to clean up tests

Replace reflect.DeepEqual with slices.Equal, which is much faster.
Remove some redundant helper functions.

Change-Id: I51b32a3d0c3fc5ad0d3b6ff0dd03f39c507e5762
GitHub-Last-Rev: e21f46d4a026b6bf6e8d912dfb8d361a20a4e779
GitHub-Pull-Request: golang/go#67609
Reviewed-on: https://go-review.googlesource.com/c/go/+/587937
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Commit-Queue: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Robert Griesemer <gri@google.com>

4 files changed, 16 insertions, 39 deletions

diff --git a/src/bytes/bytes_test.go b/src/bytes/bytes_test.go
index 200a357bc0..94301358e0 100644
--- a/src/bytes/bytes_test.go
+++ b/src/bytes/bytes_test.go
@@ -11,6 +11,7 @@ import (
 	"math"
 	"math/rand"
 	"reflect"
+	"slices"
 	"strings"
 	"testing"
 	"unicode"
@@ -18,18 +19,6 @@ import (
 	"unsafe"
 )
 
-func eq(a, b []string) bool {
-	if len(a) != len(b) {
-		return false
-	}
-	for i := 0; i < len(a); i++ {
-		if a[i] != b[i] {
-			return false
-		}
-	}
-	return true
-}
-
 func sliceOfString(s [][]byte) []string {
 	result := make([]string, len(s))
 	for i, v := range s {
@@ -808,7 +797,7 @@ func TestSplit(t *testing.T) {
 		}
 
 		result := sliceOfString(a)
-		if !eq(result, tt.a) {
+		if !slices.Equal(result, tt.a) {
 			t.Errorf(`Split(%q, %q, %d) = %v; want %v`, tt.s, tt.sep, tt.n, result, tt.a)
 			continue
 		}
@@ -866,7 +855,7 @@ func TestSplitAfter(t *testing.T) {
 		}
 
 		result := sliceOfString(a)
-		if !eq(result, tt.a) {
+		if !slices.Equal(result, tt.a) {
 			t.Errorf(`Split(%q, %q, %d) = %v; want %v`, tt.s, tt.sep, tt.n, result, tt.a)
 			continue
 		}
@@ -919,7 +908,7 @@ func TestFields(t *testing.T) {
 		}
 
 		result := sliceOfString(a)
-		if !eq(result, tt.a) {
+		if !slices.Equal(result, tt.a) {
 			t.Errorf("Fields(%q) = %v; want %v", tt.s, a, tt.a)
 			continue
 		}
@@ -939,7 +928,7 @@ func TestFieldsFunc(t *testing.T) {
 	for _, tt := range fieldstests {
 		a := FieldsFunc([]byte(tt.s), unicode.IsSpace)
 		result := sliceOfString(a)
-		if !eq(result, tt.a) {
+		if !slices.Equal(result, tt.a) {
 			t.Errorf("FieldsFunc(%q, unicode.IsSpace) = %v; want %v", tt.s, a, tt.a)
 			continue
 		}
@@ -962,7 +951,7 @@ func TestFieldsFunc(t *testing.T) {
 		}
 
 		result := sliceOfString(a)
-		if !eq(result, tt.a) {
+		if !slices.Equal(result, tt.a) {
 			t.Errorf("FieldsFunc(%q) = %v, want %v", tt.s, a, tt.a)
 		}
 
@@ -1286,18 +1275,6 @@ func TestRepeatCatchesOverflow(t *testing.T) {
 	})
 }
 
-func runesEqual(a, b []rune) bool {
-	if len(a) != len(b) {
-		return false
-	}
-	for i, r := range a {
-		if r != b[i] {
-			return false
-		}
-	}
-	return true
-}
-
 type RunesTest struct {
 	in    string
 	out   []rune
@@ -1318,7 +1295,7 @@ func TestRunes(t *testing.T) {
 	for _, tt := range RunesTests {
 		tin := []byte(tt.in)
 		a := Runes(tin)
-		if !runesEqual(a, tt.out) {
+		if !slices.Equal(a, tt.out) {
 			t.Errorf("Runes(%q) = %v; want %v", tin, a, tt.out)
 			continue
 		}
diff --git a/src/strings/search_test.go b/src/strings/search_test.go
index c01a393a12..034085043a 100644
--- a/src/strings/search_test.go
+++ b/src/strings/search_test.go
@@ -5,7 +5,7 @@
 package strings_test
 
 import (
-	"reflect"
+	"slices"
 	. "strings"
 	"testing"
 )
@@ -83,7 +83,7 @@ func TestFinderCreation(t *testing.T) {
 			}
 		}
 
-		if !reflect.DeepEqual(good, tc.suf) {
+		if !slices.Equal(good, tc.suf) {
 			t.Errorf("boyerMoore(%q) got %v want %v", tc.pattern, good, tc.suf)
 		}
 	}
diff --git a/src/strings/strings_test.go b/src/strings/strings_test.go
index 4bd3a3c202..4c8c25ee13 100644
--- a/src/strings/strings_test.go
+++ b/src/strings/strings_test.go
@@ -10,7 +10,7 @@ import (
 	"io"
 	"math"
 	"math/rand"
-	"reflect"
+	"slices"
 	"strconv"
 	. "strings"
 	"testing"
@@ -431,7 +431,7 @@ func TestSplit(t *testing.T) {
 		}
 		if tt.n < 0 {
 			b := Split(tt.s, tt.sep)
-			if !reflect.DeepEqual(a, b) {
+			if !slices.Equal(a, b) {
 				t.Errorf("Split disagrees with SplitN(%q, %q, %d) = %v; want %v", tt.s, tt.sep, tt.n, b, a)
 			}
 		}
@@ -467,7 +467,7 @@ func TestSplitAfter(t *testing.T) {
 		}
 		if tt.n < 0 {
 			b := SplitAfter(tt.s, tt.sep)
-			if !reflect.DeepEqual(a, b) {
+			if !slices.Equal(a, b) {
 				t.Errorf("SplitAfter disagrees with SplitAfterN(%q, %q, %d) = %v; want %v", tt.s, tt.sep, tt.n, b, a)
 			}
 		}
diff --git a/src/unicode/utf16/utf16_test.go b/src/unicode/utf16/utf16_test.go
index 74a4a6746b..3d434275af 100644
--- a/src/unicode/utf16/utf16_test.go
+++ b/src/unicode/utf16/utf16_test.go
@@ -6,7 +6,7 @@ package utf16_test
 
 import (
 	"internal/testenv"
-	"reflect"
+	"slices"
 	"testing"
 	"unicode"
 	. "unicode/utf16"
@@ -58,7 +58,7 @@ var encodeTests = []encodeTest{
 func TestEncode(t *testing.T) {
 	for _, tt := range encodeTests {
 		out := Encode(tt.in)
-		if !reflect.DeepEqual(out, tt.out) {
+		if !slices.Equal(out, tt.out) {
 			t.Errorf("Encode(%x) = %x; want %x", tt.in, out, tt.out)
 		}
 	}
@@ -70,7 +70,7 @@ func TestAppendRune(t *testing.T) {
 		for _, u := range tt.in {
 			out = AppendRune(out, u)
 		}
-		if !reflect.DeepEqual(out, tt.out) {
+		if !slices.Equal(out, tt.out) {
 			t.Errorf("AppendRune(%x) = %x; want %x", tt.in, out, tt.out)
 		}
 	}
@@ -143,7 +143,7 @@ func TestAllocationsDecode(t *testing.T) {
 func TestDecode(t *testing.T) {
 	for _, tt := range decodeTests {
 		out := Decode(tt.in)
-		if !reflect.DeepEqual(out, tt.out) {
+		if !slices.Equal(out, tt.out) {
 			t.Errorf("Decode(%x) = %x; want %x", tt.in, out, tt.out)
 		}
 	}