Initial commit

node_modules/react-remove-scroll/dist/es2015/handleScroll.js

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+var alwaysContainsScroll = function (node) {
+    // textarea will always _contain_ scroll inside self. It only can be hidden
+    return node.tagName === 'TEXTAREA';
+};
+var elementCanBeScrolled = function (node, overflow) {
+    if (!(node instanceof Element)) {
+        return false;
+    }
+    var styles = window.getComputedStyle(node);
+    return (
+    // not-not-scrollable
+    styles[overflow] !== 'hidden' &&
+        // contains scroll inside self
+        !(styles.overflowY === styles.overflowX && !alwaysContainsScroll(node) && styles[overflow] === 'visible'));
+};
+var elementCouldBeVScrolled = function (node) { return elementCanBeScrolled(node, 'overflowY'); };
+var elementCouldBeHScrolled = function (node) { return elementCanBeScrolled(node, 'overflowX'); };
+export var locationCouldBeScrolled = function (axis, node) {
+    var ownerDocument = node.ownerDocument;
+    var current = node;
+    do {
+        // Skip over shadow root
+        if (typeof ShadowRoot !== 'undefined' && current instanceof ShadowRoot) {
+            current = current.host;
+        }
+        var isScrollable = elementCouldBeScrolled(axis, current);
+        if (isScrollable) {
+            var _a = getScrollVariables(axis, current), scrollHeight = _a[1], clientHeight = _a[2];
+            if (scrollHeight > clientHeight) {
+                return true;
+            }
+        }
+        current = current.parentNode;
+    } while (current && current !== ownerDocument.body);
+    return false;
+};
+var getVScrollVariables = function (_a) {
+    var scrollTop = _a.scrollTop, scrollHeight = _a.scrollHeight, clientHeight = _a.clientHeight;
+    return [
+        scrollTop,
+        scrollHeight,
+        clientHeight,
+    ];
+};
+var getHScrollVariables = function (_a) {
+    var scrollLeft = _a.scrollLeft, scrollWidth = _a.scrollWidth, clientWidth = _a.clientWidth;
+    return [
+        scrollLeft,
+        scrollWidth,
+        clientWidth,
+    ];
+};
+var elementCouldBeScrolled = function (axis, node) {
+    return axis === 'v' ? elementCouldBeVScrolled(node) : elementCouldBeHScrolled(node);
+};
+var getScrollVariables = function (axis, node) {
+    return axis === 'v' ? getVScrollVariables(node) : getHScrollVariables(node);
+};
+var getDirectionFactor = function (axis, direction) {
+    /**
+     * If the element's direction is rtl (right-to-left), then scrollLeft is 0 when the scrollbar is at its rightmost position,
+     * and then increasingly negative as you scroll towards the end of the content.
+     * @see https://developer.mozilla.org/en-US/docs/Web/API/Element/scrollLeft
+     */
+    return axis === 'h' && direction === 'rtl' ? -1 : 1;
+};
+export var handleScroll = function (axis, endTarget, event, sourceDelta, noOverscroll) {
+    var directionFactor = getDirectionFactor(axis, window.getComputedStyle(endTarget).direction);
+    var delta = directionFactor * sourceDelta;
+    // find scrollable target
+    var target = event.target;
+    var targetInLock = endTarget.contains(target);
+    var shouldCancelScroll = false;
+    var isDeltaPositive = delta > 0;
+    var availableScroll = 0;
+    var availableScrollTop = 0;
+    do {
+        var _a = getScrollVariables(axis, target), position = _a[0], scroll_1 = _a[1], capacity = _a[2];
+        var elementScroll = scroll_1 - capacity - directionFactor * position;
+        if (position || elementScroll) {
+            if (elementCouldBeScrolled(axis, target)) {
+                availableScroll += elementScroll;
+                availableScrollTop += position;
+            }
+        }
+        if (target instanceof ShadowRoot) {
+            target = target.host;
+        }
+        else {
+            target = target.parentNode;
+        }
+    } while (
+    // portaled content
+    (!targetInLock && target !== document.body) ||
+        // self content
+        (targetInLock && (endTarget.contains(target) || endTarget === target)));
+    // handle epsilon around 0 (non standard zoom levels)
+    if (isDeltaPositive &&
+        ((noOverscroll && Math.abs(availableScroll) < 1) || (!noOverscroll && delta > availableScroll))) {
+        shouldCancelScroll = true;
+    }
+    else if (!isDeltaPositive &&
+        ((noOverscroll && Math.abs(availableScrollTop) < 1) || (!noOverscroll && -delta > availableScrollTop))) {
+        shouldCancelScroll = true;
+    }
+    return shouldCancelScroll;
+};