1 files changed, 83 insertions, 0 deletions
diff --git a/devtools/server/actors/highlighters/selector.js b/devtools/server/actors/highlighters/selector.js
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index 000000000..557a6d541
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+++ b/devtools/server/actors/highlighters/selector.js
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+/* 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 { isNodeValid } = require("./utils/markup");
+const { BoxModelHighlighter } = require("./box-model");
+
+// How many maximum nodes can be highlighted at the same time by the
+// SelectorHighlighter
+const MAX_HIGHLIGHTED_ELEMENTS = 100;
+
+/**
+ * The SelectorHighlighter runs a given selector through querySelectorAll on the
+ * document of the provided context node and then uses the BoxModelHighlighter
+ * to highlight the matching nodes
+ */
+function SelectorHighlighter(highlighterEnv) {
+  this.highlighterEnv = highlighterEnv;
+  this._highlighters = [];
+}
+
+SelectorHighlighter.prototype = {
+  typeName: "SelectorHighlighter",
+
+  /**
+   * Show BoxModelHighlighter on each node that matches that provided selector.
+   * @param {DOMNode} node A context node that is used to get the document on
+   * which querySelectorAll should be executed. This node will NOT be
+   * highlighted.
+   * @param {Object} options Should at least contain the 'selector' option, a
+   * string that will be used in querySelectorAll. On top of this, all of the
+   * valid options to BoxModelHighlighter.show are also valid here.
+   */
+  show: function (node, options = {}) {
+    this.hide();
+
+    if (!isNodeValid(node) || !options.selector) {
+      return false;
+    }
+
+    let nodes = [];
+    try {
+      nodes = [...node.ownerDocument.querySelectorAll(options.selector)];
+    } catch (e) {
+      // It's fine if the provided selector is invalid, nodes will be an empty
+      // array.
+    }
+
+    delete options.selector;
+
+    let i = 0;
+    for (let matchingNode of nodes) {
+      if (i >= MAX_HIGHLIGHTED_ELEMENTS) {
+        break;
+      }
+
+      let highlighter = new BoxModelHighlighter(this.highlighterEnv);
+      if (options.fill) {
+        highlighter.regionFill[options.region || "border"] = options.fill;
+      }
+      highlighter.show(matchingNode, options);
+      this._highlighters.push(highlighter);
+      i++;
+    }
+
+    return true;
+  },
+
+  hide: function () {
+    for (let highlighter of this._highlighters) {
+      highlighter.destroy();
+    }
+    this._highlighters = [];
+  },
+
+  destroy: function () {
+    this.hide();
+    this.highlighterEnv = null;
+  }
+};
+exports.SelectorHighlighter = SelectorHighlighter;