Reliability: Missing next() call in Mongoose pre-save middleware hook can cause middleware chain interruption #699

UserSchema.pre('save', async function () {
  if (!this.isModified('password')) return;  // Early return without next()
  
  const salt = await bcrypt.genSalt(10);
  this.password = await bcrypt.hash(this.password, salt);
  // Missing: next() call after hashing
});

UserSchema.pre('save', async function (next) {
  try {
    // Only hash if password is modified
    if (!this.isModified('password')) {
      return next();
    }
    
    // Hash password with salt
    const salt = await bcrypt.genSalt(10);
    this.password = await bcrypt.hash(this.password, salt);
    
    // Explicitly call next
    next();
  } catch (err) {
    // Pass error to next middleware
    next(err);
  }
});

UserSchema.pre('save', async function (next) {
  if (!this.isModified('password')) {
    return next();
  }
  
  try {
    this.password = await bcrypt.hash(this.password, 10);
  } catch (err) {
    throw err;  // Let Mongoose handle
  }
});