Support not formatting generated file.

jen/file.go

@@ -59,6 +59,8 @@ type File struct {
 	comments    []string
 	headers     []string
 	cgoPreamble []string
+	// NoFormat can be set to true to disable formatting of the generated source.
+	NoFormat bool
 	// If you're worried about generated package aliases conflicting with local variable names, you
 	// can set a prefix here. Package foo becomes {prefix}_foo.
 	PackagePrefix string

jen/jen.go

@@ -77,11 +77,15 @@ func (f *File) Render(w io.Writer) error {
 	if _, err := source.Write(body.Bytes()); err != nil {
 		return err
 	}
-	formatted, err := format.Source(source.Bytes())
-	if err != nil {
-		return fmt.Errorf("Error %s while formatting source:\n%s", err, source.String())
+	finalSource := source.Bytes()
+	if !f.NoFormat {
+		formatted, err := format.Source(source.Bytes())
+		if err != nil {
+			return fmt.Errorf("Error %s while formatting source:\n%s", err, source.String())
+		}
+		finalSource = formatted
 	}
-	if _, err := w.Write(formatted); err != nil {
+	if _, err := w.Write(finalSource); err != nil {
 		return err
 	}
 	return nil