chore(inputs.disk): Update diskio unit test (influxdata#15950)

plugins/inputs/diskio/diskio_test.go

@@ -130,20 +130,64 @@ func TestDiskIO(t *testing.T) {
 }
 
 func TestDiskIO_util(t *testing.T) {
-	ps := system.NewSystemPS()
-	diskio := &DiskIO{
-		Log: testutil.Logger{},
-		ps:  ps,
+	cts := map[string]disk.IOCountersStat{
+		"sda": {
+			ReadCount:        888,
+			WriteCount:       5341,
+			ReadBytes:        100000,
+			WriteBytes:       200000,
+			ReadTime:         7123,
+			WriteTime:        9087,
+			MergedReadCount:  11,
+			MergedWriteCount: 12,
+			Name:             "sda",
+			IoTime:           123552,
+			SerialNumber:     "ab-123-ad",
+		},
+	}
+
+	cts2 := map[string]disk.IOCountersStat{
+		"sda": {
+			ReadCount:        1000,
+			WriteCount:       6000,
+			ReadBytes:        200000,
+			WriteBytes:       300000,
+			ReadTime:         8123,
+			WriteTime:        9187,
+			MergedReadCount:  16,
+			MergedWriteCount: 30,
+			Name:             "sda",
+			IoTime:           163552,
+			SerialNumber:     "ab-123-ad",
+		},
 	}
+
 	var acc testutil.Accumulator
-	require.NoError(t, diskio.Init())
-	for i := 0; i < 3; i++ {
-		err := diskio.Gather(&acc)
-		require.NoError(t, err)
-		for _, metric := range acc.Metrics {
-			diskio.Log.Info(metric)
-		}
-		time.Sleep(3 * time.Second)
+	var mps system.MockPS
+	mps.On("DiskIO").Return(cts, nil)
+	diskio := &DiskIO{
+		Log:     testutil.Logger{},
+		Devices: []string{"sd*"},
+		ps:      &mps,
 	}
+	require.NoError(t, diskio.Init())
+	// gather
+	err := diskio.Gather(&acc)
+	require.Equal(t, nil, err)
+	// sleep
+	time.Sleep(10 * time.Second)
+	// gather twice
+	mps2 := system.MockPS{}
+	mps2.On("DiskIO").Return(cts2, nil)
+	diskio.ps = &mps2
+
+	err = diskio.Gather(&acc)
+	require.NoError(t, err)
+	require.True(t, acc.HasField("diskio", "io_util"), "miss io util")
+	require.True(t, acc.HasField("diskio", "io_svctm"), "miss io_svctm")
+	require.True(t, acc.HasField("diskio", "io_await"), "miss io_await")
 
+	require.True(t, acc.HasFloatField("diskio", "io_util"), "io_util not have value")
+	require.True(t, acc.HasFloatField("diskio", "io_svctm"), "io_svctm not have value")
+	require.True(t, acc.HasFloatField("diskio", "io_await"), "io_await not have value")
 }