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Write a function that checks if a given string includes a specific substring. Use String.prototype.includes() method.

Create a function that takes an array of numbers and returns the index of a given element. Use Array.prototype.findIndex() to implement the function.

Create a function that takes a date and a year and sets the date's UTC full year to the provided year.

Write a function that takes a date object and a number of seconds and returns a new date object with the seconds set to the provided value. Example input: setSeconds(new Date('2022-10-10T10:10:10'), 30) Expected output: new Date('2022-10-10T10:10:30')

Write a function that takes a date object and a number representing the desired month, and sets the month of the date to the given month.

Implement various functionalities using Array.prototype.slice() method

Write a function that uses the String.prototype.trimStart() method to remove any whitespace characters from the beginning of a given string.

Write a function that takes a string and a substring, and returns the index of the first occurrence of the substring in the string. If the substring is not found in the string, return -1.

Write a function that takes a string and returns an array of matched patterns using String.prototype.matchAll().

Write a function that returns the result of a string match with a given pattern.

Write a function that uses the Date.prototype.getDay() method to determine the day of the week for a given date object.

Converts a given date to a time string

Write a function that takes an array and a value as arguments and returns the index of the last occurrence of that value in the array using Array.prototype.lastIndexOf(). If the value is not found, return -1.

Implement a function that takes a string as input and returns it in lower case.

Convert a string to uppercase using String.prototype.toUpperCase();

Implement a function that returns the character at the specified index of a given string.

Create a function that concatenates two strings using the String.prototype.concat() method. The function should take two string parameters and return the concatenated string.

Create a function that takes an array and a value as arguments and adds the value to the beginning of the array using the unshift() method.

Write a function that concatenates two strings using the String.prototype.concat() method.

Write a function that flattens nested arrays using Array.prototype.flat() method.

Create a function that accepts a string and a target length. If the length of the string is less than the target length, pad the string with spaces at the beginning until the target length is reached. If the string length is greater than or equal to the target length, return the original string.

Create a function that counts the number of seconds in a given timestamp

Create a function that takes an array as input and returns a new array with the elements in reversed order.

Write a function that takes a string as input and splits it into an array of words using String.prototype.split(). Then, join the array back into a string using Array.prototype.join(). Finally, return the new string with a different delimiter separating each word.

Write a JavaScript function to find the index of an item in an array using Array.prototype.findIndex().

Convert a string to an array of Unicode code points using String.prototype.codePointAt() method.

Write a function that takes a date and returns the year in the hh:mm:ss format.

Write a function that accepts a string and a number as arguments, then returns the character at that position in the string. Use String.prototype.charAt() for this exercise.

Write a function that checks if every element in an array satisfies a given condition.

Write a function that checks whether a given string ends with the specified suffix or not.

Write a function that takes a string and a substring as arguments, and finds the last occurrence of the substring in the string. If the substring is not found, return -1.

Create a function that takes in a string and uses String.prototype.match() to find all occurrences of a pattern within the string.

Given a string, return a new string that is a substring of the original string. The substring should start at a specified index and continue until the end of the original string.

Write a function that takes a string and a regular expression and returns an array of all the substrings in the string that match the regular expression.

Write a function that returns whether a given string ends with the provided suffix or not

Create a function that returns the current date as a number (1-31).

Write a function that takes a date string as input and converts it to a UTC date string format.

In this kata, you will be working with the String.prototype.toLocaleUpperCase() method to convert a string to uppercase according to the user's locale.

Given an array of person objects, sort them alphabetically by their last name using String.prototype.localeCompare().

Implement a function that groups an array of objects by a given key and returns a new array of objects, where each object has a key and an array of objects that have that key.

Implement a function that returns true if a given string starts with a specific substring.

Create a function that replaces all occurrences of a substring with a new string.

Implement a function that takes in a Set and returns an array of entries

Sort an array of words based on their alphabetical order using String.prototype.localeCompare() method.

Implement a function that adds a value to a set using Set.prototype.add().

Create a function that slices a string based on a given start and end indexes

Create a function that takes a string as input and returns the same string in uppercase letters using the `toString()` method of the String object.

Complete the functions to find the index of an element in an array using Array.prototype.indexOf().

Write a function that finds the last index of a given element in an array using the Array.prototype.findLastIndex method.

Write a function that takes a string and a search term and returns the index of the first occurrence of the search term in the given string. If the search term is not present in the string, return -1.

Implement a function that sets the milliseconds of a given date object to a specified value.

Create a function that uses Array.prototype.every() to check if all the elements in an array meet a certain condition.

Write a function that takes a Date object and returns a string representing the time portion of the date in the current time zone using the toLocaleTimeString() method. The function should also take an optional argument specifying the locale to use.

Write a function that converts a given string to uppercase

Create a function that determines if two strings are anagrams of each other.

Create a function that takes in a string and checks if it starts with a given substring. Return a boolean indicating whether or not the string starts with the given substring.

Write a function that extracts a character from a string given an index using String.prototype.charAt()

Create a function that takes in two parameters, a string and a substring, and checks if the string includes the substring. Return a boolean value.

Create a function that takes a string and a number as arguments, and pads the string on the right side with spaces until the string reaches the desired length.

Write a function that returns the value of a given string using the String.prototype.valueOf() method.

Convert an array to a string with comma-separated values. The input array can contain numbers, strings, objects, or arrays.

Write a function that checks if a given string has a unicode character code point greater than or equal to 128. Use the String.prototype.codePointAt() method.

Write a function that takes two arrays as arguments and concatenates them into a new array using the Array.prototype.concat() method.

Create a function that uses the copyWithin method to replace specified elements within an array.

Given a sentence, split it into an array of words using the String.prototype.split() method.

Write a function that takes an array and a value and pushes the value to the end of the array using Array.prototype.push().

Write a function that takes a string and removes any trailing whitespace at the end of it using String.prototype.trimEnd().

Write a function that returns a substring of a given string, based on the start and end index provided

Write a function that takes a Date object and returns the date formatted in the user's local format using the toLocaleDateString() method.

Given an array of objects, group the objects based on a specific key and return a map object.

Create a function that takes two parameters: a string and a target substring, and returns the index of the first occurrence of the target substring in the string. If the target substring is not found, return -1.

Create an Inventory Management System that allows users to add, remove and update items in the inventory.

Create a Stock Advisor that recommends which stocks to buy based on certain parameters.

Create a function that removes white space at the end of a given string using String.prototype.trimEnd().

Write a function that checks if an element is present in an array using Array.prototype.includes() method.

Create a function that returns the current minutes.

Create a function that takes a string and a number and pads that string with a specified character until it reaches the given length.

Create a function that returns the current year using Date's built-in getFullYear method

Write a function that returns a substring of a given string, starting at a specified index and ending before a specified index.

Implement a function that takes a Date object and a number representing minutes and sets the UTC minutes of the Date object to the provided value. The function should return the updated Date object.

Implement a function that takes a Date object as input and returns a formatted string

Create a function that receives a string and a number n, the function should return the string repeated n times.

Write a function that converts a given string to its string representation using the toString() method.

This kata focuses on using String.prototype.indexOf() method.

Create a function that checks if a given string ends with a specified suffix.

Write a function that uses recursion to calculate the factorial of a given positive integer.

Write a function that takes in a string and uses precision cutting to remove all occurrences of the letter 'e'. Return the resulting string.

Create a function that receives a string and a regular expression pattern and returns an array of all the occurrences of the pattern in the string using String.prototype.matchAll().

Create a function that accepts a Set and a value to remove, and returns the updated Set after deleting the value.

Fill arrays with specific values using Array.prototype.fill()

Write a function that returns the index of the first occurrence of a given element in an array using Array.prototype.indexOf(). If the element is not found in the array, return -1.

Create a function that takes a start time and an event duration and returns the end time of the event, using the Date.prototype.setHours() method to set the hours of the start time.

Create a function that takes two parameters: a string and a regular expression. The function should return an array of all matches found in the string using the regular expression.

Given two arrays, join them to create a new array.

Write a function that checks if a given variable is an array. If it is an array, return true, otherwise return false.

Given a date, return the UTC date.

Create a function that takes in a string and a length and returns a new string with the original string padded with leading spaces if it is shorter than the provided length.

Write a function that takes in a date and returns the seconds within the minute in UTC time.

Implement the Array.prototype.with() method that returns a new array with the elements from the original array and the added elements.

Implement a function that concatenates a given string 'n' times using the String.prototype.repeat() method.