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Diffstat (limited to 'node_modules/lodash/_mergeData.js')
-rw-r--r-- | node_modules/lodash/_mergeData.js | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/node_modules/lodash/_mergeData.js b/node_modules/lodash/_mergeData.js new file mode 100644 index 0000000..cb570f9 --- /dev/null +++ b/node_modules/lodash/_mergeData.js @@ -0,0 +1,90 @@ +var composeArgs = require('./_composeArgs'), + composeArgsRight = require('./_composeArgsRight'), + replaceHolders = require('./_replaceHolders'); + +/** Used as the internal argument placeholder. */ +var PLACEHOLDER = '__lodash_placeholder__'; + +/** Used to compose bitmasks for function metadata. */ +var WRAP_BIND_FLAG = 1, + WRAP_BIND_KEY_FLAG = 2, + WRAP_CURRY_BOUND_FLAG = 4, + WRAP_CURRY_FLAG = 8, + WRAP_ARY_FLAG = 128, + WRAP_REARG_FLAG = 256; + +/* Built-in method references for those with the same name as other `lodash` methods. */ +var nativeMin = Math.min; + +/** + * Merges the function metadata of `source` into `data`. + * + * Merging metadata reduces the number of wrappers used to invoke a function. + * This is possible because methods like `_.bind`, `_.curry`, and `_.partial` + * may be applied regardless of execution order. Methods like `_.ary` and + * `_.rearg` modify function arguments, making the order in which they are + * executed important, preventing the merging of metadata. However, we make + * an exception for a safe combined case where curried functions have `_.ary` + * and or `_.rearg` applied. + * + * @private + * @param {Array} data The destination metadata. + * @param {Array} source The source metadata. + * @returns {Array} Returns `data`. + */ +function mergeData(data, source) { + var bitmask = data[1], + srcBitmask = source[1], + newBitmask = bitmask | srcBitmask, + isCommon = newBitmask < (WRAP_BIND_FLAG | WRAP_BIND_KEY_FLAG | WRAP_ARY_FLAG); + + var isCombo = + ((srcBitmask == WRAP_ARY_FLAG) && (bitmask == WRAP_CURRY_FLAG)) || + ((srcBitmask == WRAP_ARY_FLAG) && (bitmask == WRAP_REARG_FLAG) && (data[7].length <= source[8])) || + ((srcBitmask == (WRAP_ARY_FLAG | WRAP_REARG_FLAG)) && (source[7].length <= source[8]) && (bitmask == WRAP_CURRY_FLAG)); + + // Exit early if metadata can't be merged. + if (!(isCommon || isCombo)) { + return data; + } + // Use source `thisArg` if available. + if (srcBitmask & WRAP_BIND_FLAG) { + data[2] = source[2]; + // Set when currying a bound function. + newBitmask |= bitmask & WRAP_BIND_FLAG ? 0 : WRAP_CURRY_BOUND_FLAG; + } + // Compose partial arguments. + var value = source[3]; + if (value) { + var partials = data[3]; + data[3] = partials ? composeArgs(partials, value, source[4]) : value; + data[4] = partials ? replaceHolders(data[3], PLACEHOLDER) : source[4]; + } + // Compose partial right arguments. + value = source[5]; + if (value) { + partials = data[5]; + data[5] = partials ? composeArgsRight(partials, value, source[6]) : value; + data[6] = partials ? replaceHolders(data[5], PLACEHOLDER) : source[6]; + } + // Use source `argPos` if available. + value = source[7]; + if (value) { + data[7] = value; + } + // Use source `ary` if it's smaller. + if (srcBitmask & WRAP_ARY_FLAG) { + data[8] = data[8] == null ? source[8] : nativeMin(data[8], source[8]); + } + // Use source `arity` if one is not provided. + if (data[9] == null) { + data[9] = source[9]; + } + // Use source `func` and merge bitmasks. + data[0] = source[0]; + data[1] = newBitmask; + + return data; +} + +module.exports = mergeData; |