TDD Utility Library

A utility function library developed using TDD (Test-Driven Development). Provides various features including mathematical operations, data validation, and formatting.

Installation

npm install @skybaer0804/tdd

or

yarn add @skybaer0804/tdd

Usage

// Method 1: Import all functions at once
import { add, subtract, pow, divide, percent, isNum, isPositiveNum, isUrl, isInputXssSafe, toNum, toStringComma, toRenderXssSafe } from '@skybaer0804/tdd';

// Method 2: Import by category
import { add, subtract, pow, divide, percent } from '@skybaer0804/tdd/math';
import { isNum, isPositiveNum, isUrl, isInputXssSafe } from '@skybaer0804/tdd/validate';
import { toNum, toStringComma, toRenderXssSafe } from '@skybaer0804/tdd/format';

// Math functions
console.log(add(2, 3)); // 5
console.log(add('1', '2')); // 3
console.log(subtract(5, 3)); // 2
console.log(pow(2, 3)); // 8
console.log(divide(10, 2)); // 5
console.log(percent(50, 100)); // 50

// Validation functions
console.log(isNum(123)); // true
console.log(isUrl('https://example.com')); // true
console.log(isInputXssSafe('<script>alert(1)</script>')); // false

// Format functions
console.log(toNum('123')); // 123
console.log(toStringComma(1234)); // '1,234'
console.log(toRenderXssSafe('<script>alert(1)</script>')); // '&lt;script&gt;alert(1)&lt;/script&gt;'

API Documentation

Math Functions

add(a, b)

Adds two numbers. Automatically converts string numbers.

• a (number|string): First number
• b (number|string): Second number
• Returns: (number) Sum of two numbers

add(2, 3); // 5
add('1', '2'); // 3
add('1,000', '2,000'); // 3000

subtract(a, b)

Subtracts two numbers. Automatically converts string numbers.

• a (number|string): First number
• b (number|string): Second number
• Returns: (number) Difference of two numbers

subtract(5, 3); // 2
subtract('5', '3'); // 2

pow(base, exponent)

Power function. Automatically converts string numbers.

• base (number|string): Base
• exponent (number|string): Exponent
• Returns: (number) Base raised to the power of exponent

pow(2, 3); // 8
pow('2', '3'); // 8

divide(dividend, divisor)

Division function. Automatically converts string numbers.

• dividend (number|string): Number to be divided
• divisor (number|string): Number to divide by
• Returns: (number) Result of division

divide(10, 2); // 5
divide('10', '2'); // 5

percent(value, total)

Calculates percentage.

• value (number|string): Value to calculate
• total (number|string): Total value
• Returns: (number) Percentage

percent(50, 100); // 50
percent(25, 100); // 25
percent(1, 3); // 33.333...

Validate Functions

isNum(value)

Checks if a value is a number.

• value (*): Value to check
• Returns: (boolean) true if number, false otherwise

isNum(123); // true
isNum('123'); // false
isNum(null); // false

isPositiveNum(value)

Checks if a value is a non-negative integer.

• value (*): Value to check
• Returns: (boolean) true if non-negative integer, false otherwise

isPositiveNum(0); // true
isPositiveNum(1); // true
isPositiveNum(-1); // false

isUrl(value)

Checks if a value is a valid URL format.

• value (*): Value to check
• Returns: (boolean) true if valid URL, false otherwise

isUrl('https://example.com'); // true
isUrl('not-a-url'); // false

isInputXssSafe(value)

Checks if input value is safe from XSS attacks.

• value (*): Value to check
• Returns: (boolean) true if safe, false if dangerous

isInputXssSafe('Safe text'); // true
isInputXssSafe('<script>alert("XSS")</script>'); // false

Format Functions

toNum(value)

Converts a value to a number.

• value (*): Value to convert
• Returns: (number) Converted number

toNum('123'); // 123
toNum(' 12,340 '); // 12340
toNum('abc'); // NaN

toStringComma(value)

Converts a number to a string with thousand separators.

• value (number|string): Number or string to convert
• Returns: (string) String with commas

toStringComma(1234); // '1,234'
toStringComma(1234567); // '1,234,567'

toRenderXssSafe(value)

Escapes HTML special characters to prevent XSS attacks.

• value (*): Value to escape
• Returns: (string) Escaped safe string

toRenderXssSafe('Safe text'); // 'Safe text'
toRenderXssSafe('<script>alert("XSS")</script>'); // '&lt;script&gt;alert(&quot;XSS&quot;)&lt;/script&gt;'

Running Tests

npm test

Development

This project follows the TDD Red-Green-Blue cycle:

1. Red Phase: Write failing test code
2. Green Phase: Write minimal code to pass tests
3. Blue Phase: Refactor and clean up code

Changelog

1.1.0 (2024-11-10)

New Features

• Added format category (toNum, toStringComma, toRenderXssSafe)
• Extended validate category (isUrl, isInputXssSafe)
• Extended math category (percent)

Improvements

• Improved non-number input handling in math functions
• Support for automatic string number conversion
• Support for string numbers with spaces and commas

1.0.2

• Initial version
• Basic math functions (add, subtract, pow, divide)
• Basic validation functions (isNum, isPositiveNum)

License

MIT