Use throws syntax for errors in SchemasRouter.

src/Routers/SchemasRouter.js

@@ -8,13 +8,10 @@ import PromiseRouter from '../PromiseRouter';
 import * as middleware from "../middlewares";
 
 function classNameMismatchResponse(bodyClass, pathClass) {
-  return Promise.resolve({
-    status: 400,
-    response: {
-      code: Parse.Error.INVALID_CLASS_NAME,
-      error: 'class name mismatch between ' + bodyClass + ' and ' + pathClass,
-    }
-  });
+  throw new Parse.Error(
+    Parse.Error.INVALID_CLASS_NAME,
+    `Class name mismatch between ${bodyClass} and ${pathClass}.`
+  );
 }
 
 function mongoSchemaAPIResponseFields(schema) {
@@ -63,23 +60,15 @@ function createSchema(req) {
       return classNameMismatchResponse(req.body.className, req.params.className);
     }
   }
-  var className = req.params.className || req.body.className;
+
+  const className = req.params.className || req.body.className;
   if (!className) {
-    return Promise.resolve({
-      status: 400,
-      response: {
-        code: 135,
-        error: 'POST ' + req.path + ' needs class name',
-      }
-    });
+    throw new Parse.Error(135, `POST ${req.path} needs a class name.`);
   }
+
   return req.config.database.loadSchema()
     .then(schema => schema.addClassIfNotExists(className, req.body.fields))
-    .then(result => ({ response: mongoSchemaToSchemaAPIResponse(result) }))
-    .catch(error => ({
-      status: 400,
-      response: error,
-    }));
+    .then(result => ({ response: mongoSchemaToSchemaAPIResponse(result) }));
 }
 
 function modifySchema(req) {

src/Schema.js

@@ -333,29 +333,22 @@ function buildMergedSchemaObject(mongoObject, putRequest) {
 // enabled) before calling this function.
 Schema.prototype.addClassIfNotExists = function(className, fields) {
   if (this.data[className]) {
-    return Promise.reject({
-      code: Parse.Error.INVALID_CLASS_NAME,
-      error: 'class ' + className + ' already exists',
-    });
+    throw new Parse.Error(Parse.Error.INVALID_CLASS_NAME, `Class ${className} already exists.`);
   }
 
-  var mongoObject = mongoSchemaFromFieldsAndClassName(fields, className);
-
+  let mongoObject = mongoSchemaFromFieldsAndClassName(fields, className);
   if (!mongoObject.result) {
     return Promise.reject(mongoObject);
   }
 
   return this.collection.insertOne(mongoObject.result)
-  .then(result => result.ops[0])
-  .catch(error => {
-    if (error.code === 11000) { //Mongo's duplicate key error
-      return Promise.reject({
-        code: Parse.Error.INVALID_CLASS_NAME,
-        error: 'class ' + className + ' already exists',
-      });
-    }
-    return Promise.reject(error);
-  });
+    .then(result => result.ops[0])
+    .catch(error => {
+      if (error.code === 11000) { //Mongo's duplicate key error
+        throw new Parse.Error(Parse.Error.INVALID_CLASS_NAME, `Class ${className} already exists.`);
+      }
+      return Promise.reject(error);
+    });
 };
 
 // Returns a promise that resolves successfully to the new schema