Provide commonjs entry point instead umd

[TrySound]

UMD bundle has quite big wrapper which increases users bundle size. Though webpack both umd and cjs wraps with own module, rollup may optimize commonjs version

I built the following entry point with both cjs and umd

import deepmerge from './dist/{umd,cjs}.js';

console.log(deepmerge)

Here's the result of minified bundles

cjs.js: 1305
umd.js: 1557

Here's their not minified content

umd

```js var commonjsGlobal = typeof globalThis !== 'undefined' ? globalThis : typeof window !== 'undefined' ? window : typeof global !== 'undefined' ? global : typeof self !== 'undefined' ? self : {}; function createCommonjsModule(fn, module) { return module = { exports: {} }, fn(module, module.exports), module.exports; } var umd = createCommonjsModule(function (module, exports) { (function (global, factory) { module.exports = factory(); }(commonjsGlobal, function () { var isMergeableObject = function isMergeableObject(value) { return isNonNullObject(value) && !isSpecial(value) }; function isNonNullObject(value) { return !!value && typeof value === 'object' } function isSpecial(value) { var stringValue = Object.prototype.toString.call(value); return stringValue === '[object RegExp]' || stringValue === '[object Date]' || isReactElement(value) } // see https://github.com/facebook/react/blob/b5ac963fb791d1298e7f396236383bc955f916c1/src/isomorphic/classic/element/ReactElement.js#L21-L25 var canUseSymbol = typeof Symbol === 'function' && Symbol.for; var REACT_ELEMENT_TYPE = canUseSymbol ? Symbol.for('react.element') : 0xeac7; function isReactElement(value) { return value.$$typeof === REACT_ELEMENT_TYPE } function emptyTarget(val) { return Array.isArray(val) ? [] : {} } function cloneUnlessOtherwiseSpecified(value, options) { return (options.clone !== false && options.isMergeableObject(value)) ? deepmerge(emptyTarget(value), value, options) : value } function defaultArrayMerge(target, source, options) { return target.concat(source).map(function(element) { return cloneUnlessOtherwiseSpecified(element, options) }) } function getMergeFunction(key, options) { if (!options.customMerge) { return deepmerge } var customMerge = options.customMerge(key); return typeof customMerge === 'function' ? customMerge : deepmerge } function getEnumerableOwnPropertySymbols(target) { return Object.getOwnPropertySymbols ? Object.getOwnPropertySymbols(target).filter(function(symbol) { return target.propertyIsEnumerable(symbol) }) : [] } function getKeys(target) { return Object.keys(target).concat(getEnumerableOwnPropertySymbols(target)) } function mergeObject(target, source, options) { var destination = {}; if (options.isMergeableObject(target)) { getKeys(target).forEach(function(key) { destination[key] = cloneUnlessOtherwiseSpecified(target[key], options); }); } getKeys(source).forEach(function(key) { if (!options.isMergeableObject(source[key]) || !target[key]) { destination[key] = cloneUnlessOtherwiseSpecified(source[key], options); } else { destination[key] = getMergeFunction(key, options)(target[key], source[key], options); } }); return destination } function deepmerge(target, source, options) { options = options || {}; options.arrayMerge = options.arrayMerge || defaultArrayMerge; options.isMergeableObject = options.isMergeableObject || isMergeableObject; var sourceIsArray = Array.isArray(source); var targetIsArray = Array.isArray(target); var sourceAndTargetTypesMatch = sourceIsArray === targetIsArray; if (!sourceAndTargetTypesMatch) { return cloneUnlessOtherwiseSpecified(source, options) } else if (sourceIsArray) { return options.arrayMerge(target, source, options) } else { return mergeObject(target, source, options) } } deepmerge.all = function deepmergeAll(array, options) { if (!Array.isArray(array)) { throw new Error('first argument should be an array') } return array.reduce(function(prev, next) { return deepmerge(prev, next, options) }, {}) }; var deepmerge_1 = deepmerge; return deepmerge_1; })); }); console.log(umd); ```

cjs

```js var isMergeableObject = function isMergeableObject(value) { return isNonNullObject(value) && !isSpecial(value) }; function isNonNullObject(value) { return !!value && typeof value === 'object' } function isSpecial(value) { var stringValue = Object.prototype.toString.call(value); return stringValue === '[object RegExp]' || stringValue === '[object Date]' || isReactElement(value) } // see https://github.com/facebook/react/blob/b5ac963fb791d1298e7f396236383bc955f916c1/src/isomorphic/classic/element/ReactElement.js#L21-L25 var canUseSymbol = typeof Symbol === 'function' && Symbol.for; var REACT_ELEMENT_TYPE = canUseSymbol ? Symbol.for('react.element') : 0xeac7; function isReactElement(value) { return value.$$typeof === REACT_ELEMENT_TYPE } function emptyTarget(val) { return Array.isArray(val) ? [] : {} } function cloneUnlessOtherwiseSpecified(value, options) { return (options.clone !== false && options.isMergeableObject(value)) ? deepmerge(emptyTarget(value), value, options) : value } function defaultArrayMerge(target, source, options) { return target.concat(source).map(function(element) { return cloneUnlessOtherwiseSpecified(element, options) }) } function getMergeFunction(key, options) { if (!options.customMerge) { return deepmerge } var customMerge = options.customMerge(key); return typeof customMerge === 'function' ? customMerge : deepmerge } function getEnumerableOwnPropertySymbols(target) { return Object.getOwnPropertySymbols ? Object.getOwnPropertySymbols(target).filter(function(symbol) { return target.propertyIsEnumerable(symbol) }) : [] } function getKeys(target) { return Object.keys(target).concat(getEnumerableOwnPropertySymbols(target)) } function mergeObject(target, source, options) { var destination = {}; if (options.isMergeableObject(target)) { getKeys(target).forEach(function(key) { destination[key] = cloneUnlessOtherwiseSpecified(target[key], options); }); } getKeys(source).forEach(function(key) { if (!options.isMergeableObject(source[key]) || !target[key]) { destination[key] = cloneUnlessOtherwiseSpecified(source[key], options); } else { destination[key] = getMergeFunction(key, options)(target[key], source[key], options); } }); return destination } function deepmerge(target, source, options) { options = options || {}; options.arrayMerge = options.arrayMerge || defaultArrayMerge; options.isMergeableObject = options.isMergeableObject || isMergeableObject; var sourceIsArray = Array.isArray(source); var targetIsArray = Array.isArray(target); var sourceAndTargetTypesMatch = sourceIsArray === targetIsArray; if (!sourceAndTargetTypesMatch) { return cloneUnlessOtherwiseSpecified(source, options) } else if (sourceIsArray) { return options.arrayMerge(target, source, options) } else { return mergeObject(target, source, options) } } deepmerge.all = function deepmergeAll(array, options) { if (!Array.isArray(array)) { throw new Error('first argument should be an array') } return array.reduce(function(prev, next) { return deepmerge(prev, next, options) }, {}) }; var deepmerge_1 = deepmerge; var cjs = deepmerge_1; console.log(cjs); ```

[TehShrike]

Seems reasonable. My only concern is: what bundlers, if any, pay attention to the main entry point in the package.json file, and work with UMD but not CJS?

[TrySound]

I don't really know. Maybe some concatenation tools or amd builders.

[TehShrike]

I'm cool with merging this and publishing as a breaking change.

I went to see what the readme said and it already makes it seem like a CommonJS entry point is the primary one...

[TehShrike]

Published as 4.0.0

[TrySound]

Thanks!