Handle properties with question marks

The heroku schema now includes the `ca_signed?` and `self_signed?`
properties which schematic attempts to turn into this code which doesn't
compile:

        type SSLCert struct {
                ...
                CaSigned? string `json:"ca_signed?"`
        }

This updates the Go field name generation to turn `foo?` schema
properties into `IsFoo` struct fields to match Go's idioms.

cmd/schematic/schematic.go

@@ -70,6 +70,7 @@ func main() {
 
 	code, err := s.Generate()
 	if err != nil {
+		fmt.Fprintf(os.Stderr, "%s\n", code)
 		log.Fatal(err)
 	}
 

helpers.go

@@ -16,6 +16,7 @@ var helpers = template.FuncMap{
 	"initialLow":       initialLow,
 	"methodCap":        methodCap,
 	"asComment":        asComment,
+	"fieldName":        fieldName,
 	"fieldTag":         fieldTag,
 	"params":           params,
 	"requestParams":    requestParams,
@@ -51,6 +52,16 @@ func fieldTag(n string, required bool) string {
 	return fmt.Sprintf("`%s %s`", jsonTag(n, required), urlTag(n, required))
 }
 
+func fieldName(name string) string {
+	fieldName := initialCap(name)
+
+	if strings.HasSuffix(name, "?") {
+		fieldName = "Is" + strings.TrimSuffix(fieldName, "?")
+	}
+
+	return fieldName
+}
+
 func jsonTag(n string, required bool) string {
 	tags := []string{n}
 	if !required {

helpers_test.go

@@ -3,40 +3,63 @@ package schematic
 import "testing"
 
 var initialCapTests = []struct {
-	Ident     string
-	Depuncted string
+	In  string
+	Out string
 }{
 	{
-		Ident:     "provider_id",
-		Depuncted: "ProviderID",
+		In:  "provider_id",
+		Out: "ProviderID",
 	},
 	{
-		Ident:     "app-identity",
-		Depuncted: "AppIdentity",
+		In:  "app-identity",
+		Out: "AppIdentity",
 	},
 	{
-		Ident:     "uuid",
-		Depuncted: "UUID",
+		In:  "uuid",
+		Out: "UUID",
 	},
 	{
-		Ident:     "oauth-client",
-		Depuncted: "OAuthClient",
+		In:  "oauth-client",
+		Out: "OAuthClient",
 	},
 	{
-		Ident:     "Dyno all",
-		Depuncted: "DynoAll",
+		In:  "Dyno all",
+		Out: "DynoAll",
 	},
 }
 
 func TestInitialCap(t *testing.T) {
 	for i, ict := range initialCapTests {
-		depuncted := depunct(ict.Ident, true)
-		if depuncted != ict.Depuncted {
-			t.Errorf("%d: wants %v, got %v", i, ict.Depuncted, depuncted)
+		depuncted := depunct(ict.In, true)
+		if depuncted != ict.Out {
+			t.Errorf("%d: wants %v, got %v", i, ict.Out, depuncted)
 		}
 	}
 }
 
+var fieldNameTests = append([]struct {
+	In  string
+	Out string
+}{
+	{
+		In:  "ca_signed?",
+		Out: "IsCaSigned",
+	},
+},
+	initialCapTests...,
+)
+
+func TestFieldName(t *testing.T) {
+	for _, tt := range fieldNameTests {
+		t.Run(tt.In, func(t *testing.T) {
+			got := fieldName(tt.In)
+			if got != tt.Out {
+				t.Fatalf("got %q want %q", got, tt.Out)
+			}
+		})
+	}
+}
+
 var asCommentTests = []struct {
 	Comment   string
 	Commented string

templates/templates.go

@@ -2,7 +2,7 @@ package templates
 
 import "text/template"
 
-var templates = map[string]string{"field.tmpl": `{{initialCap .Name}} {{.Type}} {{fieldTag .Name .Required}} {{asComment .Definition.Description}}
+var templates = map[string]string{"field.tmpl": `{{fieldName .Name}} {{.Type}} {{fieldTag .Name .Required}} {{asComment .Definition.Description}}
 `,
 	"funcs.tmpl": `{{$Name := .Name}}
 {{$Def := .Definition}}
@@ -265,4 +265,3 @@ func Parse(t *template.Template) (*template.Template, error) {
 	}
 	return t, nil
 }
-