Merge pull request #719 from stripe/richardm-type-property

Define 'type' as a property on errors rather than a getter

lib/Error.js

@@ -11,11 +11,7 @@ class StripeError extends Error {
     super(raw.message);
     // This splat is here for back-compat and should be removed in the next major version.
     this.populate(...arguments);
-  }
-
-  // Allow `new StripeFooError(raw).type === 'StripeFooError'`
-  get type() {
-    return this.constructor.name;
+    this.type = this.constructor.name;
   }
 
   /**
@@ -71,12 +67,10 @@ class StripeError extends Error {
    */
   static extend(options) {
     const type = options.type;
-    class CustomError extends StripeError {
-      // eslint-disable-next-line class-methods-use-this
-      get type() {
-        return type;
-      }
-    }
+    class CustomError extends StripeError {}
+    Object.defineProperty(CustomError, 'name', {
+      value: type,
+    });
     delete options.type;
     Object.assign(CustomError.prototype, options);
     return CustomError;