feat: suggest manual step registration (#4)

README.md

@@ -88,6 +88,11 @@ func (s *suite) IHaveLeft(a int64) {
 func (s *suite) IHaveCukes(a int64) {
     panic("PENDING")
 }
+
+Steps can be manually registered with the runner for customization using this code:
+  Step(`^I\s+have\s+(-?\d+)\s+cukes$`, (*simpleSuite).IHaveCukes).
+  Step(`^I\s+eat\s+(-?\d+)$`, (*simpleSuite).IEat).
+  Step(`^I\s+have\s+(-?\d+)\s+left$`, (*simpleSuite).IHaveLeft)
 ```
 
 Copy these definitions into `simple_test.go`.

guess.go

@@ -2,10 +2,11 @@ package gocuke
 
 import (
 	"fmt"
-	"github.com/cucumber/common/messages/go/v17"
 	"regexp"
 	"strings"
 	"unicode"
+
+	"github.com/cucumber/common/messages/go/v17"
 )
 
 func guessMethodSig(step *messages.PickleStep) methodSig {
@@ -140,12 +141,16 @@ func (m methodSig) methodSig() string {
 	return fmt.Sprintf(`%s(%s)`, m.name, strings.Join(paramNames, ", "))
 }
 
-func (m methodSig) suggestion(suiteTypeName string) string {
+func (m methodSig) methodSuggestion(suiteTypeName string) string {
 	return fmt.Sprintf(`func (s %s) %s {
     panic("PENDING")
 }`,
 		suiteTypeName, m.methodSig())
 }
 
+func (m methodSig) stepSuggestion(suiteTypeName string) string {
+	return fmt.Sprintf("Step(`%s`, (%s).%s)", m.regex.String(), suiteTypeName, m.name)
+}
+
 var decRegex = regexp.MustCompile(`^-?\d+\.\d+$`)
 var intRegex = regexp.MustCompile(`^-?\d+$`)

run.go

@@ -1,12 +1,13 @@
 package gocuke
 
 import (
-	gherkin "github.com/cucumber/common/gherkin/go/v22"
-	"gotest.tools/v3/assert"
 	"os"
 	"path/filepath"
 	"reflect"
 	"testing"
+
+	gherkin "github.com/cucumber/common/gherkin/go/v22"
+	"gotest.tools/v3/assert"
 )
 
 // Run runs the features registered with the runner.
@@ -56,8 +57,16 @@ func (r *Runner) Run() {
 
 		suggestionText := "Missing step definitions can be fixed with the following methods:\n"
 		for _, sig := range r.suggestions {
-			suggestionText += sig.suggestion(suiteTypeName) + "\n\n"
+			suggestionText += sig.methodSuggestion(suiteTypeName) + "\n\n"
 		}
+
+		suggestionText += "Steps can be manually registered with the runner for customization using this code:\n"
+		for _, sig := range r.suggestions {
+			suggestionText += "  " + sig.stepSuggestion(suiteTypeName) + ".\n"
+		}
+		suggestionText += "\n\n"
+		suggestionText += "See https://github.com/regen-network/gocuke for further customization options."
+
 		r.topLevelT.Logf(suggestionText)
 	}
 }