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[yaffs-website] / node_modules / grunt-legacy-util / node_modules / lodash / debounce.js

diff --git a/node_modules/grunt-legacy-util/node_modules/lodash/debounce.js b/node_modules/grunt-legacy-util/node_modules/lodash/debounce.js
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+var isObject = require('./isObject'),
+    now = require('./now'),
+    toNumber = require('./toNumber');
+
+/** Used as the `TypeError` message for "Functions" methods. */
+var FUNC_ERROR_TEXT = 'Expected a function';
+
+/* Built-in method references for those with the same name as other `lodash` methods. */
+var nativeMax = Math.max;
+
+/**
+ * Creates a debounced function that delays invoking `func` until after `wait`
+ * milliseconds have elapsed since the last time the debounced function was
+ * invoked. The debounced function comes with a `cancel` method to cancel
+ * delayed `func` invocations and a `flush` method to immediately invoke them.
+ * Provide an options object to indicate whether `func` should be invoked on
+ * the leading and/or trailing edge of the `wait` timeout. The `func` is invoked
+ * with the last arguments provided to the debounced function. Subsequent calls
+ * to the debounced function return the result of the last `func` invocation.
+ *
+ * **Note:** If `leading` and `trailing` options are `true`, `func` is invoked
+ * on the trailing edge of the timeout only if the debounced function is
+ * invoked more than once during the `wait` timeout.
+ *
+ * See [David Corbacho's article](http://drupalmotion.com/article/debounce-and-throttle-visual-explanation)
+ * for details over the differences between `_.debounce` and `_.throttle`.
+ *
+ * @static
+ * @memberOf _
+ * @category Function
+ * @param {Function} func The function to debounce.
+ * @param {number} [wait=0] The number of milliseconds to delay.
+ * @param {Object} [options] The options object.
+ * @param {boolean} [options.leading=false] Specify invoking on the leading
+ *  edge of the timeout.
+ * @param {number} [options.maxWait] The maximum time `func` is allowed to be
+ *  delayed before it's invoked.
+ * @param {boolean} [options.trailing=true] Specify invoking on the trailing
+ *  edge of the timeout.
+ * @returns {Function} Returns the new debounced function.
+ * @example
+ *
+ * // Avoid costly calculations while the window size is in flux.
+ * jQuery(window).on('resize', _.debounce(calculateLayout, 150));
+ *
+ * // Invoke `sendMail` when clicked, debouncing subsequent calls.
+ * jQuery(element).on('click', _.debounce(sendMail, 300, {
+ *   'leading': true,
+ *   'trailing': false
+ * }));
+ *
+ * // Ensure `batchLog` is invoked once after 1 second of debounced calls.
+ * var debounced = _.debounce(batchLog, 250, { 'maxWait': 1000 });
+ * var source = new EventSource('/stream');
+ * jQuery(source).on('message', debounced);
+ *
+ * // Cancel the trailing debounced invocation.
+ * jQuery(window).on('popstate', debounced.cancel);
+ */
+function debounce(func, wait, options) {
+  var args,
+      maxTimeoutId,
+      result,
+      stamp,
+      thisArg,
+      timeoutId,
+      trailingCall,
+      lastCalled = 0,
+      leading = false,
+      maxWait = false,
+      trailing = true;
+
+  if (typeof func != 'function') {
+    throw new TypeError(FUNC_ERROR_TEXT);
+  }
+  wait = toNumber(wait) || 0;
+  if (isObject(options)) {
+    leading = !!options.leading;
+    maxWait = 'maxWait' in options && nativeMax(toNumber(options.maxWait) || 0, wait);
+    trailing = 'trailing' in options ? !!options.trailing : trailing;
+  }
+
+  function cancel() {
+    if (timeoutId) {
+      clearTimeout(timeoutId);
+    }
+    if (maxTimeoutId) {
+      clearTimeout(maxTimeoutId);
+    }
+    lastCalled = 0;
+    args = maxTimeoutId = thisArg = timeoutId = trailingCall = undefined;
+  }
+
+  function complete(isCalled, id) {
+    if (id) {
+      clearTimeout(id);
+    }
+    maxTimeoutId = timeoutId = trailingCall = undefined;
+    if (isCalled) {
+      lastCalled = now();
+      result = func.apply(thisArg, args);
+      if (!timeoutId && !maxTimeoutId) {
+        args = thisArg = undefined;
+      }
+    }
+  }
+
+  function delayed() {
+    var remaining = wait - (now() - stamp);
+    if (remaining <= 0 || remaining > wait) {
+      complete(trailingCall, maxTimeoutId);
+    } else {
+      timeoutId = setTimeout(delayed, remaining);
+    }
+  }
+
+  function flush() {
+    if ((timeoutId && trailingCall) || (maxTimeoutId && trailing)) {
+      result = func.apply(thisArg, args);
+    }
+    cancel();
+    return result;
+  }
+
+  function maxDelayed() {
+    complete(trailing, timeoutId);
+  }
+
+  function debounced() {
+    args = arguments;
+    stamp = now();
+    thisArg = this;
+    trailingCall = trailing && (timeoutId || !leading);
+
+    if (maxWait === false) {
+      var leadingCall = leading && !timeoutId;
+    } else {
+      if (!lastCalled && !maxTimeoutId && !leading) {
+        lastCalled = stamp;
+      }
+      var remaining = maxWait - (stamp - lastCalled),
+          isCalled = remaining <= 0 || remaining > maxWait;
+
+      if (isCalled) {
+        if (maxTimeoutId) {
+          maxTimeoutId = clearTimeout(maxTimeoutId);
+        }
+        lastCalled = stamp;
+        result = func.apply(thisArg, args);
+      }
+      else if (!maxTimeoutId) {
+        maxTimeoutId = setTimeout(maxDelayed, remaining);
+      }
+    }
+    if (isCalled && timeoutId) {
+      timeoutId = clearTimeout(timeoutId);
+    }
+    else if (!timeoutId && wait !== maxWait) {
+      timeoutId = setTimeout(delayed, wait);
+    }
+    if (leadingCall) {
+      isCalled = true;
+      result = func.apply(thisArg, args);
+    }
+    if (isCalled && !timeoutId && !maxTimeoutId) {
+      args = thisArg = undefined;
+    }
+    return result;
+  }
+  debounced.cancel = cancel;
+  debounced.flush = flush;
+  return debounced;
+}
+
+module.exports = debounce;