Merge pull request #13571 from Automattic/vkarpov15/gh-13570

fix(query): throw readable error when executing a Query instance without an associated model

Author: vkarpov15

lib/query.js

@@ -4360,7 +4360,10 @@ Query.prototype.exec = async function exec(op) {
   }
 
   if (this.op == null) {
-    throw new Error('Query must have `op` before executing');
+    throw new MongooseError('Query must have `op` before executing');
+  }
+  if (this.model == null) {
+    throw new MongooseError('Query must have an associated model before executing');
   }
   this._validateOp();
 
@@ -4440,6 +4443,13 @@ function _executePostExecHooks(query) {
  */
 
 function _executePostHooks(query, res, error, op) {
+  if (query._queryMiddleware == null) {
+    if (error != null) {
+      throw error;
+    }
+    return res;
+  }
+
   return new Promise((resolve, reject) => {
     const opts = error ? { error } : {};
 
@@ -4473,6 +4483,10 @@ function _executePreExecHooks(query) {
  */
 
 function _executePreHooks(query, op) {
+  if (query._queryMiddleware == null) {
+    return;
+  }
+
   return new Promise((resolve, reject) => {
     query._queryMiddleware.execPre(op || query.op, query, [], (error) => {
       if (error != null) {

test/query.test.js

@@ -4094,6 +4094,7 @@ describe('Query', function() {
     await Test.findOneAndUpdate({}, { name: 'bar' });
     assert.ok(!('projection' in lastOptions));
   });
+
   it('should provide a clearer error message when sorting with empty string', async function() {
     const testSchema = new Schema({
       name: { type: String }
@@ -4104,6 +4105,32 @@ describe('Query', function() {
       await Error.find().sort('-');
     }, { message: 'Invalid field "" passed to sort()' });
   });
+
+  it('throws a readable error when executing Query instance without a model (gh-13570)', async function() {
+    const schema = new Schema({ name: String });
+    const M = db.model('Test', schema, 'Test');
+    await M.deleteMany({});
+    await M.create({ name: 'gh13570' });
+
+    const Q = new mongoose.Query();
+    await assert.rejects(
+      () => Q.collection('Test').find().lean(),
+      /Query must have an associated model before executing/
+    );
+  });
+
+  it('throws a readable error when executing Query instance without an op (gh-13570)', async function() {
+    const schema = new Schema({ name: String });
+    const M = db.model('Test', schema, 'Test');
+    await M.deleteMany({});
+    await M.create({ name: 'gh13570' });
+
+    const Q = new M.Query();
+    await assert.rejects(
+      () => Q.lean(),
+      /Query must have `op` before executing/
+    );
+  });
   it('converts findOneAndUpdate to findOneAndReplace if overwrite set (gh-13550)', async function() {
     const testSchema = new Schema({
       name: { type: String }