fix(gen): Improve enum value generation

- Treat dashes in enum values the same as underscores
- Ignore spaces
- Normalize uppercase values to TitleCase

Closes: #502

Author: abdusco

gen/templates.go

@@ -105,19 +105,7 @@ var templateFunctions = template.FuncMap{
 	"generateTags":       strmangle.GenerateTags,
 	"generateIgnoreTags": strmangle.GenerateIgnoreTags,
 	"normalizeType":      NormalizeType,
-	"enumVal": func(val string) string {
-		var newval strings.Builder
-		for _, r := range val {
-			if r == '_' || unicode.IsLetter(r) || unicode.IsDigit(r) {
-				newval.WriteRune(r)
-				continue
-			}
-			newval.WriteString(fmt.Sprintf("U%x", r))
-		}
-
-		// Title case after doing unicode replacements or they will be stripped
-		return strmangle.TitleCase(newval.String())
-	},
+	"enumVal":            enumValToIdentifier,
 	"columnTagName": func(casing, name, alias string) string {
 		switch casing {
 		case "camel":
@@ -149,6 +137,24 @@ var templateFunctions = template.FuncMap{
 	"relQueryMethodName": relQueryMethodName,
 }
 
+func enumValToIdentifier(val string) string {
+	val = strings.ToLower(val)
+	val = strings.ReplaceAll(val, "-", "_")
+	val = strings.ReplaceAll(val, " ", "_")
+
+	var newval strings.Builder
+	for _, r := range val {
+		if r == '_' || unicode.IsLetter(r) || unicode.IsDigit(r) {
+			newval.WriteRune(r)
+			continue
+		}
+		newval.WriteString(fmt.Sprintf("U%x", r))
+	}
+
+	// Title case after doing unicode replacements or they will be stripped
+	return strmangle.TitleCase(newval.String())
+}
+
 func relQueryMethodName(tAlias drivers.TableAlias, relAlias string) string {
 	for _, colAlias := range tAlias.Columns {
 		// clash with field name

gen/templates_test.go

@@ -0,0 +1,26 @@
+package gen
+
+import "testing"
+
+func Test_enumValToIdentifier(t *testing.T) {
+	tests := []struct {
+		val      string
+		expected string
+	}{
+		{"in_progress", "InProgress"},
+		{"in-progress", "InProgress"},
+		{"in progress", "InProgress"},
+		{"IN_PROGRESS", "InProgress"},
+		{"in___-__progress", "InProgress"},
+		{" in progress ", "InProgress"},
+		// This is OK, because enum values are prefixed with the type name, e.g. TaskStatus1InProgress
+		{"1-in-progress", "1InProgress"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.val, func(t *testing.T) {
+			if actual := enumValToIdentifier(tt.val); actual != tt.expected {
+				t.Errorf("enumValToIdentifier(%q) = %q; want %q", tt.val, actual, tt.expected)
+			}
+		})
+	}
+}