golangci-lint/CI: Bump versions and introduce new linters (#798)

* golangci-lint/CI: Bump versions

Fix remaining linter issues

* Specifically set AppVeyor version

* Fix the infamous typos 👀

* Add go env cmd to AppVeyor

* Add go version cmd to AppVeyor

* Specify AppVeyor image, adjust linters

* Update go get to go install due to deprecation

* Bump golangci-lint timeout time for AppVeyor

* Change NW contract to NQ

* Address nitters

* GetRandomPair -> Pair{}

* Address nits

* Address time nitterinos plus additional tweaks

* More time inception upgrades!

* Bending time and space

exchanges/kline/kline.go

@@ -19,8 +19,7 @@ func CreateKline(trades []order.TradeHistory, interval Interval, p currency.Pair
 		return Item{}, fmt.Errorf("invalid time interval: [%s]", interval)
 	}
 
-	err := validateData(trades)
-	if err != nil {
+	if err := validateData(trades); err != nil {
 		return Item{}, err
 	}
 

exchanges/kline/kline_test.go

@@ -92,7 +92,7 @@ func TestValidateData(t *testing.T) {
 
 func TestCreateKline(t *testing.T) {
 	t.Parallel()
-	c, err := CreateKline(nil,
+	_, err := CreateKline(nil,
 		OneMin,
 		currency.NewPair(currency.BTC, currency.USD),
 		asset.Spot,
@@ -113,7 +113,7 @@ func TestCreateKline(t *testing.T) {
 		})
 	}
 
-	c, err = CreateKline(trades,
+	_, err = CreateKline(trades,
 		0,
 		currency.NewPair(currency.BTC, currency.USD),
 		asset.Spot,
@@ -122,7 +122,7 @@ func TestCreateKline(t *testing.T) {
 		t.Fatal("error cannot be nil")
 	}
 
-	c, err = CreateKline(trades,
+	c, err := CreateKline(trades,
 		OneMin,
 		currency.NewPair(currency.BTC, currency.USD),
 		asset.Spot,
@@ -251,6 +251,8 @@ func TestDurationToWord(t *testing.T) {
 	for x := range testCases {
 		test := testCases[x]
 		t.Run(test.name, func(t *testing.T) {
+			t.Parallel()
+			t.Helper()
 			v := durationToWord(test.interval)
 			if !strings.EqualFold(v, test.name) {
 				t.Fatalf("%v: received %v expected %v", test.name, v, test.name)
@@ -261,7 +263,7 @@ func TestDurationToWord(t *testing.T) {
 
 func TestKlineErrors(t *testing.T) {
 	t.Parallel()
-	v := ErrorKline{
+	v := Error{
 		Interval: OneYear,
 		Pair:     currency.NewPair(currency.BTC, currency.AUD),
 		Err:      errors.New("hello world"),
@@ -398,6 +400,7 @@ func TestTotalCandlesPerInterval(t *testing.T) {
 	for x := range testCases {
 		test := testCases[x]
 		t.Run(test.name, func(t *testing.T) {
+			t.Parallel()
 			v := TotalCandlesPerInterval(start, end, test.interval)
 			if v != test.expected {
 				t.Fatalf("%v: received %v expected %v", test.name, v, test.expected)
@@ -506,6 +509,7 @@ func TestItem_SortCandlesByTimestamp(t *testing.T) {
 }
 
 func setupTest(t *testing.T) {
+	t.Helper()
 	if verbose {
 		testhelpers.EnableVerboseTestOutput()
 	}

exchanges/kline/kline_types.go

@@ -128,8 +128,8 @@ type ExchangeCapabilitiesEnabled struct {
 // Interval type for kline Interval usage
 type Interval time.Duration
 
-// ErrorKline struct to hold kline interval errors
-type ErrorKline struct {
+// Error struct to hold kline interval errors
+type Error struct {
 	Asset    asset.Item
 	Pair     currency.Pair
 	Interval Interval
@@ -137,13 +137,13 @@ type ErrorKline struct {
 }
 
 // Error returns short interval unsupported message
-func (k *ErrorKline) Error() string {
-	return k.Err.Error()
+func (e *Error) Error() string {
+	return e.Err.Error()
 }
 
 // Unwrap returns interval unsupported message
-func (k *ErrorKline) Unwrap() error {
-	return k.Err
+func (e *Error) Unwrap() error {
+	return e.Err
 }
 
 // IntervalRangeHolder holds the entire range of intervals