tool/exchange_wrapper_coverage: fix regression and implement reflection (#837)

* cmd/tools/exchange: fix regression and implement reflection so as this can dynamically scale to our interface

* exchanges: add comment and fix whoopsie

* exchanges: fix linter issues

* wrapper_cov_tool: add actual full interface method count to get a better perceived deployment

* exchanges/tool: addr glorious nits

* kraken: remove string in test

* exchange_template_tool: fix tmpl issue

exchanges/exmo/exmo_test.go

@@ -2,8 +2,10 @@ package exmo
 
 import (
 	"context"
+	"errors"
 	"log"
 	"os"
+	"sync"
 	"testing"
 	"time"
 
@@ -51,6 +53,20 @@ func TestMain(m *testing.M) {
 	os.Exit(m.Run())
 }
 
+func TestStart(t *testing.T) {
+	t.Parallel()
+	err := e.Start(nil)
+	if !errors.Is(err, common.ErrNilPointer) {
+		t.Fatalf("received: '%v' but expected: '%v'", err, common.ErrNilPointer)
+	}
+	var testWg sync.WaitGroup
+	err = e.Start(&testWg)
+	if err != nil {
+		t.Fatal(err)
+	}
+	testWg.Wait()
+}
+
 func TestGetTrades(t *testing.T) {
 	t.Parallel()
 	_, err := e.GetTrades(context.Background(), "BTC_USD")

exchanges/exmo/exmo_wrapper.go

@@ -124,6 +124,9 @@ func (e *EXMO) SetDefaults() {
 
 // Setup takes in the supplied exchange configuration details and sets params
 func (e *EXMO) Setup(exch *config.Exchange) error {
+	if err := exch.Validate(); err != nil {
+		return err
+	}
 	if !exch.Enabled {
 		e.SetEnabled(false)
 		return nil
@@ -132,12 +135,16 @@ func (e *EXMO) Setup(exch *config.Exchange) error {
 }
 
 // Start starts the EXMO go routine
-func (e *EXMO) Start(wg *sync.WaitGroup) {
+func (e *EXMO) Start(wg *sync.WaitGroup) error {
+	if wg == nil {
+		return fmt.Errorf("%T %w", wg, common.ErrNilPointer)
+	}
 	wg.Add(1)
 	go func() {
 		e.Run()
 		wg.Done()
 	}()
+	return nil
 }
 
 // Run implements the EXMO wrapper
@@ -598,6 +605,9 @@ func (e *EXMO) WithdrawFiatFundsToInternationalBank(_ context.Context, _ *withdr
 
 // GetFeeByType returns an estimate of fee based on type of transaction
 func (e *EXMO) GetFeeByType(ctx context.Context, feeBuilder *exchange.FeeBuilder) (float64, error) {
+	if feeBuilder == nil {
+		return 0, fmt.Errorf("%T %w", feeBuilder, common.ErrNilPointer)
+	}
 	if !e.AllowAuthenticatedRequest() && // Todo check connection status
 		feeBuilder.FeeType == exchange.CryptocurrencyTradeFee {
 		feeBuilder.FeeType = exchange.OfflineTradeFee