Bump to v3.0.0.

internal/baseCallback.js

@@ -0,0 +1,34 @@
+var baseMatches = require('./baseMatches'),
+    baseProperty = require('./baseProperty'),
+    baseToString = require('./baseToString'),
+    bindCallback = require('./bindCallback'),
+    identity = require('../utility/identity'),
+    isBindable = require('./isBindable');
+
+/**
+ * The base implementation of `_.callback` which supports specifying the
+ * number of arguments to provide to `func`.
+ *
+ * @private
+ * @param {*} [func=_.identity] The value to convert to a callback.
+ * @param {*} [thisArg] The `this` binding of `func`.
+ * @param {number} [argCount] The number of arguments to provide to `func`.
+ * @returns {Function} Returns the callback.
+ */
+function baseCallback(func, thisArg, argCount) {
+  var type = typeof func;
+  if (type == 'function') {
+    return (typeof thisArg != 'undefined' && isBindable(func))
+      ? bindCallback(func, thisArg, argCount)
+      : func;
+  }
+  if (func == null) {
+    return identity;
+  }
+  // Handle "_.property" and "_.matches" style callback shorthands.
+  return type == 'object'
+    ? baseMatches(func, !argCount)
+    : baseProperty(argCount ? baseToString(func) : func);
+}
+
+module.exports = baseCallback;