Simplify system.DiskUsage() (#2630)

plugins/inputs/system/mock_PS.go

@@ -1,6 +1,8 @@
 package system
 
 import (
+	"os"
+
 	"github.com/stretchr/testify/mock"
 
 	"github.com/shirou/gopsutil/cpu"
@@ -13,6 +15,16 @@ import (
 
 type MockPS struct {
 	mock.Mock
+	PSDiskDeps
+}
+
+type MockPSDisk struct {
+	*systemPS
+	*mock.Mock
+}
+
+type mockDiskUsage struct {
+	*mock.Mock
 }
 
 func (m *MockPS) LoadAvg() (*load.AvgStat, error) {
@@ -96,3 +108,35 @@ func (m *MockPS) NetConnections() ([]net.ConnectionStat, error) {
 
 	return r0, r1
 }
+
+func (m *mockDiskUsage) Partitions(all bool) ([]disk.PartitionStat, error) {
+	ret := m.Called(all)
+
+	r0 := ret.Get(0).([]disk.PartitionStat)
+	r1 := ret.Error(1)
+
+	return r0, r1
+}
+
+func (m *mockDiskUsage) OSGetenv(key string) string {
+	ret := m.Called(key)
+	return ret.Get(0).(string)
+}
+
+func (m *mockDiskUsage) OSStat(name string) (os.FileInfo, error) {
+	ret := m.Called(name)
+
+	r0 := ret.Get(0).(os.FileInfo)
+	r1 := ret.Error(1)
+
+	return r0, r1
+}
+
+func (m *mockDiskUsage) PSDiskUsage(path string) (*disk.UsageStat, error) {
+	ret := m.Called(path)
+
+	r0 := ret.Get(0).(*disk.UsageStat)
+	r1 := ret.Error(1)
+
+	return r0, r1
+}