check-modify

Simple text checkers and modifiers for forms.

Installation

npm install --save check-modify

If you are using React

You may be interested in using these checkers/modifiers with the validating higher order component from the react-validating-controlled NPM package.

Using both, you can quickly create custom components for text inputs/areas, selects, radios, and checkboxes, as well as more complicated custom components.

What's a checker/modifier?

Checkers and modifiers are function generators of functions that take a single String argument (the text to check or modify).

Checkers generate functions that return a Boolean value indicating whether the String argument passes some criterion.

Validators generate functions that return a String value transformation of the String argument

Function signatures

Checker: function(any) --> function(String) --> Boolean

Modifier: function(any) --> function(String) --> String

Example

import { CharacterLimitChecker, CharacterLimitModifier } from 'check-modify';

const checker = CharacterLimitChecker(5);
console.log( checker("abc")     ); // prints "true"
console.log( checker("abcdefg") ); // prints "false"

const modifier = CharacterLimitModifier(5);
console.log( modifier("abc")     ); // prints "abc"
console.log( modifier("abcdefg") ); // prints "abcde"

Note: Currently, there is no option to reference a minified version directly. Rather, import/require the modules you need.

Quick reference

Composition

You can compose any number of checkers and modifiers, including with checkers and modifiers you write yourself. What is actually composed is the generated functions, not the function generators.

Composing checkers

import { composeCheckers, CharacterLimitChecker, MinimumCharacterLimitChecker } from 'check-modify';

const upperChecker = CharacterLimitChecker(8);
const lowerChecker = MinimumCharacterLimitChecker(4);
const composed = composeCheckers(upperChecker, lowerChecker);

console.log( composed("abc")        ); // prints "false"
console.log( composed("abcde")      ); // prints "true"
console.log( composed("abcdefghij") ); // prints "false"

Composing modifiers

import { composeModifiers, CharacterLimitModifier } from 'check-modify';

const Repeater = function() {
  return function(text) {
    return text + text;
  };
};
const truncator = CharacterLimitModifier(2);
const composed = composeModifiers(truncator, Repeater(), Repeater());

console.log( composed("abcdefghij") ); // prints "abababab"

Note: Composed modifiers are applied in order.

Provided checkers and modifiers

For more details about each provided checker and modifier, check the tests accompanying each.

| Checker name (and arguments) | Description
| -------------------------------------- | --------------------------------------------------------------- | CharacterLimitChecker(limit) | Is text shorter than limit characters? | MinimumCharacterLimitChecker(limit) | Is text longer than limit characters? | CurrencyChecker() | Does text have only currency characters (numbers, commas, periods, spaces)? | EmailChecker() | * Is text a valid email? | KeywordCountChecker(countLimit) | Are there fewer than countLimit comma separated phrases? | KeywordLengthChecker(characterLimit) | * Is each comma separated phrase shorter than characterLimit? | LinkChecker() | * Is text a valid HTTP(S) link? | ShortenedLinkChecker() | * Is text NOT a shortened link (e.g. t.co/...)? | PasswordChecker() | * Does text have at least 8 characters, containing at least one letter and number? | PhoneNumberChecker() | * Is text a valid 10 digit phone number? | ZipCodeChecker() | * Is text a valid 5 digit zip code?

Checkers whose description begins with * are intended to be used as a final check on input values just before form submission. The rest are intended to be used to check whether text changes in an input should be allowed to happen.

| Modifier name (and arguments) | Description
| ---------------------------------- | --------------------------------------------------------------- | CharacterLimitModifier(limit) | Truncates text to limit characters | CurrencyOnChangeModifier() | Places commas in correct locations, and enforces max 2 decimal digits | CurrencyOnBlurModifier(maxValue) | Adds a decimal point if needed, fills out any missing zeros, and limits value to maxValue | KeywordOnChangeModifier() | Strips all characters except letters, numbers, ",", "-", and " " | KeywordOnBlurModifier() | Reformats valid keywords with ", " separator | PhoneNumberOnChangeModifier() | Strips all characters except numbers, "-", " ", "(", and ")" | PhoneNumberOnBlurModifier() | Formats 10 digit phone numbers like (123) 456-7890 | ZipCodeOnChangeModifier() | Strips all characters except numbers and "-" | ZipCodeOnBlurModifier() | Keeps up to 5 numeric characters preceeding the first "-"

Modifer names sometimes include either OnChange or OnBlur to indicate the intended use of the modifier with text inputs.

Contributing

Setup

You will want to clone the repository and npm install.

Testing

npm test: Tests all modules

Branch pushes to Github will trigger CI tests on CircleCI.

Building lib

The lib directory contains transpiled code that is gets shipped. To update this directory, npm run build and commit changes.