1 files changed, 67 insertions, 0 deletions
diff --git a/devtools/server/actors/object/symbol-iterator.js b/devtools/server/actors/object/symbol-iterator.js
new file mode 100644
index 0000000000..e0b05f9cd1
--- /dev/null
+++ b/devtools/server/actors/object/symbol-iterator.js
@@ -0,0 +1,67 @@
+/* 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 { Actor } = require("resource://devtools/shared/protocol.js");
+const { symbolIteratorSpec } = require("resource://devtools/shared/specs/symbol-iterator.js");
+
+const DevToolsUtils = require("resource://devtools/shared/DevToolsUtils.js");
+
+/**
+ * Creates an actor to iterate over an object's symbols.
+ *
+ * @param objectActor ObjectActor
+ *        The object actor.
+ */
+class SymbolIteratorActor extends Actor {
+  constructor(objectActor, conn) {
+    super(conn, symbolIteratorSpec);
+
+    let symbols = [];
+    if (DevToolsUtils.isSafeDebuggerObject(objectActor.obj)) {
+      try {
+        symbols = objectActor.obj.getOwnPropertySymbols();
+      } catch (err) {
+        // The above can throw when the debuggee does not subsume the object's
+        // compartment, or for some WrappedNatives like Cu.Sandbox.
+      }
+    }
+
+    this.iterator = {
+      size: symbols.length,
+      symbolDescription(index) {
+        const symbol = symbols[index];
+        return {
+          name: symbol.toString(),
+          descriptor: objectActor._propertyDescriptor(symbol),
+        };
+      },
+    };
+  }
+
+  form() {
+    return {
+      type: this.typeName,
+      actor: this.actorID,
+      count: this.iterator.size,
+    };
+  }
+
+  slice({ start, count }) {
+    const ownSymbols = [];
+    for (let i = start, m = start + count; i < m; i++) {
+      ownSymbols.push(this.iterator.symbolDescription(i));
+    }
+    return {
+      ownSymbols,
+    };
+  }
+
+  all() {
+    return this.slice({ start: 0, count: this.iterator.size });
+  }
+}
+
+exports.SymbolIteratorActor = SymbolIteratorActor;