gecko-dev/devtools/client/inspector/breadcrumbs.js

937 строки
28 KiB
JavaScript

/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
/* vim: set ft=javascript ts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
"use strict";
const promise = require("promise");
const {ELLIPSIS} = require("devtools/shared/l10n");
const MAX_LABEL_LENGTH = 40;
const NS_XHTML = "http://www.w3.org/1999/xhtml";
const SCROLL_REPEAT_MS = 100;
const EventEmitter = require("devtools/shared/event-emitter");
const KeyShortcuts = require("devtools/client/shared/key-shortcuts");
// Some margin may be required for visible element detection.
const SCROLL_MARGIN = 1;
/**
* Component to replicate functionality of XUL arrowscrollbox
* for breadcrumbs
*
* @param {Window} win The window containing the breadcrumbs
* @parem {DOMNode} container The element in which to put the scroll box
*/
function ArrowScrollBox(win, container) {
this.win = win;
this.doc = win.document;
this.container = container;
EventEmitter.decorate(this);
this.init();
}
ArrowScrollBox.prototype = {
// Scroll behavior, exposed for testing
scrollBehavior: "smooth",
/**
* Build the HTML, add to the DOM and start listening to
* events
*/
init: function() {
this.constructHtml();
this.onUnderflow();
this.onScroll = this.onScroll.bind(this);
this.onStartBtnClick = this.onStartBtnClick.bind(this);
this.onEndBtnClick = this.onEndBtnClick.bind(this);
this.onStartBtnDblClick = this.onStartBtnDblClick.bind(this);
this.onEndBtnDblClick = this.onEndBtnDblClick.bind(this);
this.onUnderflow = this.onUnderflow.bind(this);
this.onOverflow = this.onOverflow.bind(this);
this.inner.addEventListener("scroll", this.onScroll);
this.startBtn.addEventListener("mousedown", this.onStartBtnClick);
this.endBtn.addEventListener("mousedown", this.onEndBtnClick);
this.startBtn.addEventListener("dblclick", this.onStartBtnDblClick);
this.endBtn.addEventListener("dblclick", this.onEndBtnDblClick);
// Overflow and underflow are moz specific events
this.inner.addEventListener("underflow", this.onUnderflow);
this.inner.addEventListener("overflow", this.onOverflow);
},
/**
* Determine whether the current text directionality is RTL
*/
isRtl: function() {
return this.doc.dir === "rtl";
},
/**
* Scroll to the specified element using the current scroll behavior
* @param {Element} element element to scroll
* @param {String} block desired alignment of element after scrolling
*/
scrollToElement: function(element, block) {
element.scrollIntoView({ block: block, behavior: this.scrollBehavior });
},
/**
* Call the given function once; then continuously
* while the mouse button is held
* @param {Function} repeatFn the function to repeat while the button is held
*/
clickOrHold: function(repeatFn) {
let timer;
let container = this.container;
function handleClick() {
cancelHold();
repeatFn();
}
let window = this.win;
function cancelHold() {
window.clearTimeout(timer);
container.removeEventListener("mouseout", cancelHold);
container.removeEventListener("mouseup", handleClick);
}
function repeated() {
repeatFn();
timer = window.setTimeout(repeated, SCROLL_REPEAT_MS);
}
container.addEventListener("mouseout", cancelHold);
container.addEventListener("mouseup", handleClick);
timer = window.setTimeout(repeated, SCROLL_REPEAT_MS);
},
/**
* When start button is dbl clicked scroll to first element
*/
onStartBtnDblClick: function() {
let children = this.inner.childNodes;
if (children.length < 1) {
return;
}
let element = this.inner.childNodes[0];
this.scrollToElement(element, "start");
},
/**
* When end button is dbl clicked scroll to last element
*/
onEndBtnDblClick: function() {
let children = this.inner.childNodes;
if (children.length < 1) {
return;
}
let element = children[children.length - 1];
this.scrollToElement(element, "start");
},
/**
* When start arrow button is clicked scroll towards first element
*/
onStartBtnClick: function() {
let scrollToStart = () => {
let element = this.getFirstInvisibleElement();
if (!element) {
return;
}
let block = this.isRtl() ? "end" : "start";
this.scrollToElement(element, block);
};
this.clickOrHold(scrollToStart);
},
/**
* When end arrow button is clicked scroll towards last element
*/
onEndBtnClick: function() {
let scrollToEnd = () => {
let element = this.getLastInvisibleElement();
if (!element) {
return;
}
let block = this.isRtl() ? "start" : "end";
this.scrollToElement(element, block);
};
this.clickOrHold(scrollToEnd);
},
/**
* Event handler for scrolling, update the
* enabled/disabled status of the arrow buttons
*/
onScroll: function() {
let first = this.getFirstInvisibleElement();
if (!first) {
this.startBtn.setAttribute("disabled", "true");
} else {
this.startBtn.removeAttribute("disabled");
}
let last = this.getLastInvisibleElement();
if (!last) {
this.endBtn.setAttribute("disabled", "true");
} else {
this.endBtn.removeAttribute("disabled");
}
},
/**
* On underflow, make the arrow buttons invisible
*/
onUnderflow: function() {
this.startBtn.style.visibility = "collapse";
this.endBtn.style.visibility = "collapse";
this.emit("underflow");
},
/**
* On overflow, show the arrow buttons
*/
onOverflow: function() {
this.startBtn.style.visibility = "visible";
this.endBtn.style.visibility = "visible";
this.emit("overflow");
},
/**
* Check whether the element is to the left of its container but does
* not also span the entire container.
* @param {Number} left the left scroll point of the container
* @param {Number} right the right edge of the container
* @param {Number} elementLeft the left edge of the element
* @param {Number} elementRight the right edge of the element
*/
elementLeftOfContainer: function(left, right, elementLeft, elementRight) {
return elementLeft < (left - SCROLL_MARGIN)
&& elementRight < (right - SCROLL_MARGIN);
},
/**
* Check whether the element is to the right of its container but does
* not also span the entire container.
* @param {Number} left the left scroll point of the container
* @param {Number} right the right edge of the container
* @param {Number} elementLeft the left edge of the element
* @param {Number} elementRight the right edge of the element
*/
elementRightOfContainer: function(left, right, elementLeft, elementRight) {
return elementLeft > (left + SCROLL_MARGIN)
&& elementRight > (right + SCROLL_MARGIN);
},
/**
* Get the first (i.e. furthest left for LTR)
* non or partly visible element in the scroll box
*/
getFirstInvisibleElement: function() {
let elementsList = Array.from(this.inner.childNodes).reverse();
let predicate = this.isRtl() ?
this.elementRightOfContainer : this.elementLeftOfContainer;
return this.findFirstWithBounds(elementsList, predicate);
},
/**
* Get the last (i.e. furthest right for LTR)
* non or partly visible element in the scroll box
*/
getLastInvisibleElement: function() {
let predicate = this.isRtl() ?
this.elementLeftOfContainer : this.elementRightOfContainer;
return this.findFirstWithBounds(this.inner.childNodes, predicate);
},
/**
* Find the first element that matches the given predicate, called with bounds
* information
* @param {Array} elements an ordered list of elements
* @param {Function} predicate a function to be called with bounds
* information
*/
findFirstWithBounds: function(elements, predicate) {
let left = this.inner.scrollLeft;
let right = left + this.inner.clientWidth;
for (let element of elements) {
let elementLeft = element.offsetLeft - element.parentElement.offsetLeft;
let elementRight = elementLeft + element.offsetWidth;
// Check that the starting edge of the element is out of the visible area
// and that the ending edge does not span the whole container
if (predicate(left, right, elementLeft, elementRight)) {
return element;
}
}
return null;
},
/**
* Build the HTML for the scroll box and insert it into the DOM
*/
constructHtml: function() {
this.startBtn = this.createElement("div", "scrollbutton-up",
this.container);
this.createElement("div", "toolbarbutton-icon", this.startBtn);
this.createElement("div", "arrowscrollbox-overflow-start-indicator",
this.container);
this.inner = this.createElement("div", "html-arrowscrollbox-inner",
this.container);
this.createElement("div", "arrowscrollbox-overflow-end-indicator",
this.container);
this.endBtn = this.createElement("div", "scrollbutton-down",
this.container);
this.createElement("div", "toolbarbutton-icon", this.endBtn);
},
/**
* Create an XHTML element with the given class name, and append it to the
* parent.
* @param {String} tagName name of the tag to create
* @param {String} className class of the element
* @param {DOMNode} parent the parent node to which it should be appended
* @return {DOMNode} The new element
*/
createElement: function(tagName, className, parent) {
let el = this.doc.createElementNS(NS_XHTML, tagName);
el.className = className;
if (parent) {
parent.appendChild(el);
}
return el;
},
/**
* Remove event handlers and clean up
*/
destroy: function() {
this.inner.removeEventListener("scroll", this.onScroll);
this.startBtn.removeEventListener("mousedown",
this.onStartBtnClick);
this.endBtn.removeEventListener("mousedown", this.onEndBtnClick);
this.startBtn.removeEventListener("dblclick",
this.onStartBtnDblClick);
this.endBtn.removeEventListener("dblclick",
this.onRightBtnDblClick);
// Overflow and underflow are moz specific events
this.inner.removeEventListener("underflow", this.onUnderflow);
this.inner.removeEventListener("overflow", this.onOverflow);
},
};
/**
* Display the ancestors of the current node and its children.
* Only one "branch" of children are displayed (only one line).
*
* Mechanism:
* - If no nodes displayed yet:
* then display the ancestor of the selected node and the selected node;
* else select the node;
* - If the selected node is the last node displayed, append its first (if any).
*
* @param {InspectorPanel} inspector The inspector hosting this widget.
*/
function HTMLBreadcrumbs(inspector) {
this.inspector = inspector;
this.selection = this.inspector.selection;
this.win = this.inspector.panelWin;
this.doc = this.inspector.panelDoc;
this._init();
}
exports.HTMLBreadcrumbs = HTMLBreadcrumbs;
HTMLBreadcrumbs.prototype = {
get walker() {
return this.inspector.walker;
},
_init: function() {
this.outer = this.doc.getElementById("inspector-breadcrumbs");
this.arrowScrollBox = new ArrowScrollBox(
this.win,
this.outer);
this.container = this.arrowScrollBox.inner;
this.scroll = this.scroll.bind(this);
this.arrowScrollBox.on("overflow", this.scroll);
this.outer.addEventListener("click", this, true);
this.outer.addEventListener("mouseover", this, true);
this.outer.addEventListener("mouseout", this, true);
this.outer.addEventListener("focus", this, true);
this.shortcuts = new KeyShortcuts({ window: this.win, target: this.outer });
this.handleShortcut = this.handleShortcut.bind(this);
this.shortcuts.on("Right", this.handleShortcut);
this.shortcuts.on("Left", this.handleShortcut);
// We will save a list of already displayed nodes in this array.
this.nodeHierarchy = [];
// Last selected node in nodeHierarchy.
this.currentIndex = -1;
// Used to build a unique breadcrumb button Id.
this.breadcrumbsWidgetItemId = 0;
this.update = this.update.bind(this);
this.updateWithMutations = this.updateWithMutations.bind(this);
this.updateSelectors = this.updateSelectors.bind(this);
this.selection.on("new-node-front", this.update);
this.selection.on("pseudoclass", this.updateSelectors);
this.selection.on("attribute-changed", this.updateSelectors);
this.inspector.on("markupmutation", this.updateWithMutations);
this.update();
},
/**
* Build a string that represents the node: tagName#id.class1.class2.
* @param {NodeFront} node The node to pretty-print
* @return {String}
*/
prettyPrintNodeAsText: function(node) {
let text = node.displayName;
if (node.isPseudoElement) {
text = node.isBeforePseudoElement ? "::before" : "::after";
}
if (node.id) {
text += "#" + node.id;
}
if (node.className) {
let classList = node.className.split(/\s+/);
for (let i = 0; i < classList.length; i++) {
text += "." + classList[i];
}
}
for (let pseudo of node.pseudoClassLocks) {
text += pseudo;
}
return text;
},
/**
* Build <span>s that represent the node:
* <span class="breadcrumbs-widget-item-tag">tagName</span>
* <span class="breadcrumbs-widget-item-id">#id</span>
* <span class="breadcrumbs-widget-item-classes">.class1.class2</span>
* @param {NodeFront} node The node to pretty-print
* @returns {DocumentFragment}
*/
prettyPrintNodeAsXHTML: function(node) {
let tagLabel = this.doc.createElementNS(NS_XHTML, "span");
tagLabel.className = "breadcrumbs-widget-item-tag plain";
let idLabel = this.doc.createElementNS(NS_XHTML, "span");
idLabel.className = "breadcrumbs-widget-item-id plain";
let classesLabel = this.doc.createElementNS(NS_XHTML, "span");
classesLabel.className = "breadcrumbs-widget-item-classes plain";
let pseudosLabel = this.doc.createElementNS(NS_XHTML, "span");
pseudosLabel.className = "breadcrumbs-widget-item-pseudo-classes plain";
let tagText = node.displayName;
if (node.isPseudoElement) {
tagText = node.isBeforePseudoElement ? "::before" : "::after";
}
let idText = node.id ? ("#" + node.id) : "";
let classesText = "";
if (node.className) {
let classList = node.className.split(/\s+/);
for (let i = 0; i < classList.length; i++) {
classesText += "." + classList[i];
}
}
// Figure out which element (if any) needs ellipsing.
// Substring for that element, then clear out any extras
// (except for pseudo elements).
let maxTagLength = MAX_LABEL_LENGTH;
let maxIdLength = MAX_LABEL_LENGTH - tagText.length;
let maxClassLength = MAX_LABEL_LENGTH - tagText.length - idText.length;
if (tagText.length > maxTagLength) {
tagText = tagText.substr(0, maxTagLength) + ELLIPSIS;
idText = classesText = "";
} else if (idText.length > maxIdLength) {
idText = idText.substr(0, maxIdLength) + ELLIPSIS;
classesText = "";
} else if (classesText.length > maxClassLength) {
classesText = classesText.substr(0, maxClassLength) + ELLIPSIS;
}
tagLabel.textContent = tagText;
idLabel.textContent = idText;
classesLabel.textContent = classesText;
pseudosLabel.textContent = node.pseudoClassLocks.join("");
let fragment = this.doc.createDocumentFragment();
fragment.appendChild(tagLabel);
fragment.appendChild(idLabel);
fragment.appendChild(classesLabel);
fragment.appendChild(pseudosLabel);
return fragment;
},
/**
* Generic event handler.
* @param {DOMEvent} event.
*/
handleEvent: function(event) {
if (event.type == "click" && event.button == 0) {
this.handleClick(event);
} else if (event.type == "mouseover") {
this.handleMouseOver(event);
} else if (event.type == "mouseout") {
this.handleMouseOut(event);
} else if (event.type == "focus") {
this.handleFocus(event);
}
},
/**
* Focus event handler. When breadcrumbs container gets focus,
* aria-activedescendant needs to be updated to currently selected
* breadcrumb. Ensures that the focus stays on the container at all times.
* @param {DOMEvent} event.
*/
handleFocus: function(event) {
event.stopPropagation();
let node = this.nodeHierarchy[this.currentIndex];
if (node) {
this.outer.setAttribute("aria-activedescendant", node.button.id);
} else {
this.outer.removeAttribute("aria-activedescendant");
}
this.outer.focus();
},
/**
* On click navigate to the correct node.
* @param {DOMEvent} event.
*/
handleClick: function(event) {
let target = event.originalTarget;
if (target.tagName == "button") {
target.onBreadcrumbsClick();
}
},
/**
* On mouse over, highlight the corresponding content DOM Node.
* @param {DOMEvent} event.
*/
handleMouseOver: function(event) {
let target = event.originalTarget;
if (target.tagName == "button") {
target.onBreadcrumbsHover();
}
},
/**
* On mouse out, make sure to unhighlight.
* @param {DOMEvent} event.
*/
handleMouseOut: function(event) {
this.inspector.toolbox.highlighterUtils.unhighlight();
},
/**
* Handle a keyboard shortcut supported by the breadcrumbs widget.
*
* @param {String} name
* Name of the keyboard shortcut received.
* @param {DOMEvent} event
* Original event that triggered the shortcut.
*/
handleShortcut: function(event) {
if (!this.selection.isElementNode()) {
return;
}
event.preventDefault();
event.stopPropagation();
this.keyPromise = (this.keyPromise || promise.resolve(null)).then(() => {
let currentnode;
const isLeft = event.code === "ArrowLeft";
const isRight = event.code === "ArrowRight";
if (isLeft && this.currentIndex != 0) {
currentnode = this.nodeHierarchy[this.currentIndex - 1];
} else if (isRight && this.currentIndex < this.nodeHierarchy.length - 1) {
currentnode = this.nodeHierarchy[this.currentIndex + 1];
} else {
return null;
}
this.outer.setAttribute("aria-activedescendant", currentnode.button.id);
return this.selection.setNodeFront(currentnode.node, { reason: "breadcrumbs" });
});
},
/**
* Remove nodes and clean up.
*/
destroy: function() {
this.selection.off("new-node-front", this.update);
this.selection.off("pseudoclass", this.updateSelectors);
this.selection.off("attribute-changed", this.updateSelectors);
this.inspector.off("markupmutation", this.updateWithMutations);
this.container.removeEventListener("click", this, true);
this.container.removeEventListener("mouseover", this, true);
this.container.removeEventListener("mouseout", this, true);
this.container.removeEventListener("focus", this, true);
this.shortcuts.destroy();
this.empty();
this.arrowScrollBox.off("overflow", this.scroll);
this.arrowScrollBox.destroy();
this.arrowScrollBox = null;
this.outer = null;
this.container = null;
this.nodeHierarchy = null;
this.isDestroyed = true;
},
/**
* Empty the breadcrumbs container.
*/
empty: function() {
while (this.container.hasChildNodes()) {
this.container.firstChild.remove();
}
},
/**
* Set which button represent the selected node.
* @param {Number} index Index of the displayed-button to select.
*/
setCursor: function(index) {
// Unselect the previously selected button
if (this.currentIndex > -1
&& this.currentIndex < this.nodeHierarchy.length) {
this.nodeHierarchy[this.currentIndex].button.removeAttribute("checked");
}
if (index > -1) {
this.nodeHierarchy[index].button.setAttribute("checked", "true");
} else {
// Unset active active descendant when all buttons are unselected.
this.outer.removeAttribute("aria-activedescendant");
}
this.currentIndex = index;
},
/**
* Get the index of the node in the cache.
* @param {NodeFront} node.
* @returns {Number} The index for this node or -1 if not found.
*/
indexOf: function(node) {
for (let i = this.nodeHierarchy.length - 1; i >= 0; i--) {
if (this.nodeHierarchy[i].node === node) {
return i;
}
}
return -1;
},
/**
* Remove all the buttons and their references in the cache after a given
* index.
* @param {Number} index.
*/
cutAfter: function(index) {
while (this.nodeHierarchy.length > (index + 1)) {
let toRemove = this.nodeHierarchy.pop();
this.container.removeChild(toRemove.button);
}
},
/**
* Build a button representing the node.
* @param {NodeFront} node The node from the page.
* @return {DOMNode} The <button> for this node.
*/
buildButton: function(node) {
let button = this.doc.createElementNS(NS_XHTML, "button");
button.appendChild(this.prettyPrintNodeAsXHTML(node));
button.className = "breadcrumbs-widget-item";
button.id = "breadcrumbs-widget-item-" + this.breadcrumbsWidgetItemId++;
button.setAttribute("tabindex", "-1");
button.setAttribute("title", this.prettyPrintNodeAsText(node));
button.onclick = () => {
button.focus();
};
button.onBreadcrumbsClick = () => {
this.selection.setNodeFront(node, { reason: "breadcrumbs" });
};
button.onBreadcrumbsHover = () => {
this.inspector.toolbox.highlighterUtils.highlightNodeFront(node);
};
return button;
},
/**
* Connecting the end of the breadcrumbs to a node.
* @param {NodeFront} node The node to reach.
*/
expand: function(node) {
let fragment = this.doc.createDocumentFragment();
let lastButtonInserted = null;
let originalLength = this.nodeHierarchy.length;
let stopNode = null;
if (originalLength > 0) {
stopNode = this.nodeHierarchy[originalLength - 1].node;
}
while (node && node != stopNode) {
if (node.tagName) {
let button = this.buildButton(node);
fragment.insertBefore(button, lastButtonInserted);
lastButtonInserted = button;
this.nodeHierarchy.splice(originalLength, 0, {
node,
button,
currentPrettyPrintText: this.prettyPrintNodeAsText(node)
});
}
node = node.parentNode();
}
this.container.appendChild(fragment, this.container.firstChild);
},
/**
* Find the "youngest" ancestor of a node which is already in the breadcrumbs.
* @param {NodeFront} node.
* @return {Number} Index of the ancestor in the cache, or -1 if not found.
*/
getCommonAncestor: function(node) {
while (node) {
let idx = this.indexOf(node);
if (idx > -1) {
return idx;
}
node = node.parentNode();
}
return -1;
},
/**
* Ensure the selected node is visible.
*/
scroll: function() {
// FIXME bug 684352: make sure its immediate neighbors are visible too.
if (!this.isDestroyed) {
let element = this.nodeHierarchy[this.currentIndex].button;
this.arrowScrollBox.scrollToElement(element, "end");
}
},
/**
* Update all button outputs.
*/
updateSelectors: function() {
if (this.isDestroyed) {
return;
}
for (let i = this.nodeHierarchy.length - 1; i >= 0; i--) {
let {node, button, currentPrettyPrintText} = this.nodeHierarchy[i];
// If the output of the node doesn't change, skip the update.
let textOutput = this.prettyPrintNodeAsText(node);
if (currentPrettyPrintText === textOutput) {
continue;
}
// Otherwise, update the whole markup for the button.
while (button.hasChildNodes()) {
button.firstChild.remove();
}
button.appendChild(this.prettyPrintNodeAsXHTML(node));
button.setAttribute("title", textOutput);
this.nodeHierarchy[i].currentPrettyPrintText = textOutput;
}
},
/**
* Given a list of mutation changes (passed by the markupmutation event),
* decide whether or not they are "interesting" to the current state of the
* breadcrumbs widget, i.e. at least one of them should cause part of the
* widget to be updated.
* @param {Array} mutations The mutations array.
* @return {Boolean}
*/
_hasInterestingMutations: function(mutations) {
if (!mutations || !mutations.length) {
return false;
}
for (let {type, added, removed, target, attributeName} of mutations) {
if (type === "childList") {
// Only interested in childList mutations if the added or removed
// nodes are currently displayed.
return added.some(node => this.indexOf(node) > -1) ||
removed.some(node => this.indexOf(node) > -1);
} else if (type === "attributes" && this.indexOf(target) > -1) {
// Only interested in attributes mutations if the target is
// currently displayed, and the attribute is either id or class.
return attributeName === "class" || attributeName === "id";
}
}
// Catch all return in case the mutations array was empty, or in case none
// of the changes iterated above were interesting.
return false;
},
/**
* Update the breadcrumbs display when a new node is selected and there are
* mutations.
* @param {Array} mutations An array of mutations in case this was called as
* the "markupmutation" event listener.
*/
updateWithMutations(mutations) {
return this.update("markupmutation", mutations);
},
/**
* Update the breadcrumbs display when a new node is selected.
* @param {String} reason The reason for the update, if any.
* @param {Array} mutations An array of mutations in case this was called as
* the "markupmutation" event listener.
*/
update: function(reason, mutations) {
if (this.isDestroyed) {
return;
}
let hasInterestingMutations = this._hasInterestingMutations(mutations);
if (reason === "markupmutation" && !hasInterestingMutations) {
return;
}
if (!this.selection.isConnected()) {
// remove all the crumbs
this.cutAfter(-1);
return;
}
// If this was an interesting deletion; then trim the breadcrumb trail
let trimmed = false;
if (reason === "markupmutation") {
for (let {type, removed} of mutations) {
if (type !== "childList") {
continue;
}
for (let node of removed) {
let removedIndex = this.indexOf(node);
if (removedIndex > -1) {
this.cutAfter(removedIndex - 1);
trimmed = true;
}
}
}
}
if (!this.selection.isElementNode()) {
// no selection
this.setCursor(-1);
if (trimmed) {
// Since something changed, notify the interested parties.
this.inspector.emit("breadcrumbs-updated", this.selection.nodeFront);
}
return;
}
let idx = this.indexOf(this.selection.nodeFront);
// Is the node already displayed in the breadcrumbs?
// (and there are no mutations that need re-display of the crumbs)
if (idx > -1 && !hasInterestingMutations) {
// Yes. We select it.
this.setCursor(idx);
} else {
// No. Is the breadcrumbs display empty?
if (this.nodeHierarchy.length > 0) {
// No. We drop all the element that are not direct ancestors
// of the selection
let parent = this.selection.nodeFront.parentNode();
let ancestorIdx = this.getCommonAncestor(parent);
this.cutAfter(ancestorIdx);
}
// we append the missing button between the end of the breadcrumbs display
// and the current node.
this.expand(this.selection.nodeFront);
// we select the current node button
idx = this.indexOf(this.selection.nodeFront);
this.setCursor(idx);
}
let doneUpdating = this.inspector.updating("breadcrumbs");
this.updateSelectors();
// Make sure the selected node and its neighbours are visible.
setTimeout(() => {
try {
this.scroll();
this.inspector.emit("breadcrumbs-updated", this.selection.nodeFront);
doneUpdating();
} catch (e) {
// Only log this as an error if we haven't been destroyed in the meantime.
if (!this.isDestroyed) {
console.error(e);
}
}
}, 0);
}
};