var defaultIsMergeableObject = require('is-mergeable-object')
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function emptyTarget(val) {
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return Array.isArray(val) ? [] : {}
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}
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function cloneUnlessOtherwiseSpecified(value, options) {
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return (options.clone !== false && options.isMergeableObject(value))
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? deepmerge(emptyTarget(value), value, options)
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: value
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}
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function defaultArrayMerge(target, source, options) {
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return target.concat(source).map(function(element) {
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return cloneUnlessOtherwiseSpecified(element, options)
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})
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}
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function getMergeFunction(key, options) {
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if (!options.customMerge) {
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return deepmerge
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}
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var customMerge = options.customMerge(key)
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return typeof customMerge === 'function' ? customMerge : deepmerge
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}
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function getEnumerableOwnPropertySymbols(target) {
|
return Object.getOwnPropertySymbols
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? Object.getOwnPropertySymbols(target).filter(function(symbol) {
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return target.propertyIsEnumerable(symbol)
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})
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: []
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}
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|
function getKeys(target) {
|
return Object.keys(target).concat(getEnumerableOwnPropertySymbols(target))
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}
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|
function propertyIsOnObject(object, property) {
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try {
|
return property in object
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} catch(_) {
|
return false
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}
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}
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// Protects from prototype poisoning and unexpected merging up the prototype chain.
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function propertyIsUnsafe(target, key) {
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return propertyIsOnObject(target, key) // Properties are safe to merge if they don't exist in the target yet,
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&& !(Object.hasOwnProperty.call(target, key) // unsafe if they exist up the prototype chain,
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&& Object.propertyIsEnumerable.call(target, key)) // and also unsafe if they're nonenumerable.
|
}
|
|
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 (propertyIsUnsafe(target, key)) {
|
return
|
}
|
|
if (propertyIsOnObject(target, key) && options.isMergeableObject(source[key])) {
|
destination[key] = getMergeFunction(key, options)(target[key], source[key], options)
|
} else {
|
destination[key] = cloneUnlessOtherwiseSpecified(source[key], options)
|
}
|
})
|
return destination
|
}
|
|
function deepmerge(target, source, options) {
|
options = options || {}
|
options.arrayMerge = options.arrayMerge || defaultArrayMerge
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options.isMergeableObject = options.isMergeableObject || defaultIsMergeableObject
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// cloneUnlessOtherwiseSpecified is added to `options` so that custom arrayMerge()
|
// implementations can use it. The caller may not replace it.
|
options.cloneUnlessOtherwiseSpecified = cloneUnlessOtherwiseSpecified
|
|
var sourceIsArray = Array.isArray(source)
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var targetIsArray = Array.isArray(target)
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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)
|
}, {})
|
}
|
|
module.exports = deepmerge
|
