react app

react-app/node_modules/lodash/internal/mergeData.js

@@ -0,0 +1,89 @@
+var arrayCopy = require('./arrayCopy'),
+    composeArgs = require('./composeArgs'),
+    composeArgsRight = require('./composeArgsRight'),
+    replaceHolders = require('./replaceHolders');
+
+/** Used to compose bitmasks for wrapper metadata. */
+var BIND_FLAG = 1,
+    CURRY_BOUND_FLAG = 4,
+    CURRY_FLAG = 8,
+    ARY_FLAG = 128,
+    REARG_FLAG = 256;
+
+/** Used as the internal argument placeholder. */
+var PLACEHOLDER = '__lodash_placeholder__';
+
+/* Native 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 required 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`
+ * augment function arguments, making the order in which they are executed important,
+ * preventing the merging of metadata. However, we make an exception for a safe
+ * common 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 < ARY_FLAG;
+
+  var isCombo =
+    (srcBitmask == ARY_FLAG && bitmask == CURRY_FLAG) ||
+    (srcBitmask == ARY_FLAG && bitmask == REARG_FLAG && data[7].length <= source[8]) ||
+    (srcBitmask == (ARY_FLAG | REARG_FLAG) && bitmask == CURRY_FLAG);
+
+  // Exit early if metadata can't be merged.
+  if (!(isCommon || isCombo)) {
+    return data;
+  }
+  // Use source `thisArg` if available.
+  if (srcBitmask & BIND_FLAG) {
+    data[2] = source[2];
+    // Set when currying a bound function.
+    newBitmask |= (bitmask & BIND_FLAG) ? 0 : CURRY_BOUND_FLAG;
+  }
+  // Compose partial arguments.
+  var value = source[3];
+  if (value) {
+    var partials = data[3];
+    data[3] = partials ? composeArgs(partials, value, source[4]) : arrayCopy(value);
+    data[4] = partials ? replaceHolders(data[3], PLACEHOLDER) : arrayCopy(source[4]);
+  }
+  // Compose partial right arguments.
+  value = source[5];
+  if (value) {
+    partials = data[5];
+    data[5] = partials ? composeArgsRight(partials, value, source[6]) : arrayCopy(value);
+    data[6] = partials ? replaceHolders(data[5], PLACEHOLDER) : arrayCopy(source[6]);
+  }
+  // Use source `argPos` if available.
+  value = source[7];
+  if (value) {
+    data[7] = arrayCopy(value);
+  }
+  // Use source `ary` if it's smaller.
+  if (srcBitmask & 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;