diff --git a/go/hack/hack_test.go b/go/hack/hack_test.go
index cf8b6423aff..9f71d82cf11 100644
--- a/go/hack/hack_test.go
+++ b/go/hack/hack_test.go
@@ -20,21 +20,30 @@ package hack
 
 import (
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestByteToString(t *testing.T) {
 	v1 := []byte("1234")
-	if s := String(v1); s != "1234" {
-		t.Errorf("String(\"1234\"): %q, want 1234", s)
-	}
+	s := String(v1)
+	assert.Equal(t, "1234", s)
 
 	v1 = []byte("")
-	if s := String(v1); s != "" {
-		t.Errorf("String(\"\"): %q, want empty", s)
-	}
+	s = String(v1)
+	assert.Equal(t, "", s)
 
 	v1 = nil
-	if s := String(v1); s != "" {
-		t.Errorf("String(\"\"): %q, want empty", s)
-	}
+	s = String(v1)
+	assert.Equal(t, "", s)
+}
+
+func TestStringToByte(t *testing.T) {
+	s := "1234"
+	b := StringBytes(s)
+	assert.Equal(t, []byte("1234"), b)
+
+	s = ""
+	b = StringBytes(s)
+	assert.Nil(t, b)
 }
diff --git a/go/ioutil/meter_test.go b/go/ioutil/meter_test.go
new file mode 100644
index 00000000000..10e2b83b485
--- /dev/null
+++ b/go/ioutil/meter_test.go
@@ -0,0 +1,58 @@
+/*
+Copyright 2024 The Vitess Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package ioutil
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+var (
+	calledBytes    int
+	calledDuration time.Duration
+)
+
+func testfn(b int, d time.Duration) {
+	calledBytes = b
+	calledDuration = d
+}
+
+func TestMeter(t *testing.T) {
+	tm := meter{
+		fs:       []func(b int, d time.Duration){testfn},
+		bytes:    123,
+		duration: time.Second,
+	}
+
+	assert.Equal(t, int64(123), tm.Bytes())
+	assert.Equal(t, time.Second, tm.Duration())
+
+	tf := func(p []byte) (int, error) {
+		return 1, nil
+	}
+
+	b, err := tm.measure(tf, []byte(""))
+	wantDuration := time.Second + calledDuration
+	wantBytes := int64(123) + int64(calledBytes)
+
+	assert.NoError(t, err)
+	assert.Equal(t, 1, b)
+	assert.Equal(t, wantDuration, tm.duration)
+	assert.Equal(t, wantBytes, tm.bytes)
+}
diff --git a/go/ioutil/reader_test.go b/go/ioutil/reader_test.go
new file mode 100644
index 00000000000..ea284f13225
--- /dev/null
+++ b/go/ioutil/reader_test.go
@@ -0,0 +1,55 @@
+/*
+Copyright 2024 The Vitess Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package ioutil
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type mockReadCloser struct{}
+
+func (*mockReadCloser) Read([]byte) (int, error) {
+	return 2, nil
+}
+
+func (*mockReadCloser) Close() error {
+	return nil
+}
+
+type mockRead struct{}
+
+func (*mockRead) Read([]byte) (int, error) {
+	return 3, nil
+}
+
+func TestMeteredReader(t *testing.T) {
+	mrc := NewMeteredReadCloser(&mockReadCloser{}, testfn)
+	n, err := mrc.Read([]byte(""))
+	assert.NoError(t, err)
+	assert.Equal(t, 2, n)
+	assert.Equal(t, 2, calledBytes)
+	assert.Equal(t, calledDuration, mrc.Duration())
+
+	mr := NewMeteredReader(&mockRead{}, testfn)
+	n, err = mr.Read([]byte(""))
+	assert.NoError(t, err)
+	assert.Equal(t, 3, n)
+	assert.Equal(t, 3, calledBytes)
+	assert.Equal(t, calledDuration, mr.Duration())
+}
diff --git a/go/ioutil/writer_test.go b/go/ioutil/writer_test.go
new file mode 100644
index 00000000000..b21fb34b397
--- /dev/null
+++ b/go/ioutil/writer_test.go
@@ -0,0 +1,55 @@
+/*
+Copyright 2024 The Vitess Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package ioutil
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type mockWriteCloser struct{}
+
+func (*mockWriteCloser) Write([]byte) (int, error) {
+	return 2, nil
+}
+
+func (*mockWriteCloser) Close() error {
+	return nil
+}
+
+type mockWrite struct{}
+
+func (*mockWrite) Write([]byte) (int, error) {
+	return 3, nil
+}
+
+func TestMeteredWriter(t *testing.T) {
+	mwc := NewMeteredWriteCloser(&mockWriteCloser{}, testfn)
+	n, err := mwc.Write([]byte(""))
+	assert.NoError(t, err)
+	assert.Equal(t, 2, n)
+	assert.Equal(t, 2, calledBytes)
+	assert.Equal(t, calledDuration, mwc.Duration())
+
+	mw := NewMeteredWriter(&mockWrite{}, testfn)
+	n, err = mw.Write([]byte(""))
+	assert.NoError(t, err)
+	assert.Equal(t, 3, n)
+	assert.Equal(t, 3, calledBytes)
+	assert.Equal(t, calledDuration, mw.Duration())
+}
diff --git a/go/jsonutil/json_test.go b/go/jsonutil/json_test.go
index 50488dd3f3c..00d53d92021 100644
--- a/go/jsonutil/json_test.go
+++ b/go/jsonutil/json_test.go
@@ -18,6 +18,8 @@ package jsonutil
 
 import (
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestMarshalNoEscape(t *testing.T) {
@@ -53,9 +55,7 @@ func TestMarshalNoEscape(t *testing.T) {
 		t.Run(c.name, func(t *testing.T) {
 			json, _ := MarshalNoEscape(c.v)
 			sjson := string(json[:len(json)-1])
-			if sjson != c.expected {
-				t.Errorf("expected: %v, got: %v", c.expected, sjson)
-			}
+			assert.Equal(t, c.expected, sjson)
 		})
 	}
 }
@@ -97,9 +97,7 @@ func TestMarshalIndentNoEscape(t *testing.T) {
 		t.Run(c.name, func(t *testing.T) {
 			json, _ := MarshalIndentNoEscape(c.v, c.prefix, c.ident)
 			sjson := string(json[:len(json)-1])
-			if sjson != c.expected {
-				t.Errorf("expected: %v, got: %v", c.expected, sjson)
-			}
+			assert.Equal(t, c.expected, sjson)
 		})
 	}
 }