1 files changed, 149 insertions, 0 deletions
diff --git a/devtools/shared/commands/script/script-command.js b/devtools/shared/commands/script/script-command.js
new file mode 100644
index 0000000000..93917944d5
--- /dev/null
+++ b/devtools/shared/commands/script/script-command.js
@@ -0,0 +1,149 @@
+/* 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 {
+  getAdHocFrontOrPrimitiveGrip,
+  // eslint-disable-next-line mozilla/reject-some-requires
+} = require("resource://devtools/client/fronts/object.js");
+
+class ScriptCommand {
+  constructor({ commands }) {
+    this._commands = commands;
+  }
+
+  /**
+   * Execute a JavaScript expression.
+   *
+   * @param {String} expression: The code you want to evaluate.
+   * @param {Object} options: Options for evaluation:
+   * @param {Object} options.frameActor: a FrameActor ID. The actor holds a reference to
+   *        a Debugger.Frame. This option allows you to evaluate the string in the frame
+   *        of the given FrameActor.
+   * @param {String} options.url: the url to evaluate the script as. Defaults to "debugger eval code".
+   * @param {TargetFront} options.selectedTargetFront: When passed, the expression will be
+   *        evaluated in the context of the target (as opposed to the default, top-level one).
+   * @param {String} options.selectedNodeActor: A NodeActor ID that may be used by helper
+   *        functions that can reference the currently selected node in the Inspector, like $0.
+   * @param {String} options.selectedObjectActor: the actorID of a given objectActor.
+   *        This is used by context menu entries to get a reference to an object, in order
+   *        to perform some operation on it (copy it, store it as a global variable, …).
+   * @param {Number} options.innerWindowID: An optional window id to be used for the evaluation,
+   *        instead of the regular webConsoleActor.evalWindow.
+   *        This is used by functions that may want to evaluate in a different window (for
+   *        example a non-remote iframe), like getting the elements of a given document.
+   * @param {object} options.mapped: An optional object indicating if the original expression
+   *        entered by the users have been modified
+   * @param {boolean} options.mapped.await: true if the expression was a top-level await
+   *        expression that was wrapped in an async-iife
+   *
+   * @return {Promise}: A promise that resolves with the response.
+   */
+  async execute(expression, options = {}) {
+    const {
+      selectedObjectActor,
+      selectedNodeActor,
+      frameActor,
+      selectedTargetFront,
+    } = options;
+
+    // Retrieve the right WebConsole front that relates either to (by order of priority):
+    // - the currently selected target in the context selector
+    //   (selectedTargetFront argument),
+    // - the object picked in the console (when using store as global) (selectedObjectActor),
+    // - the currently selected Node in the inspector (selectedNodeActor),
+    // - the currently selected frame in the debugger (when paused) (frameActor),
+    // - the currently selected target in the iframe dropdown
+    //   (selectedTargetFront from the TargetCommand)
+    let targetFront = this._commands.targetCommand.selectedTargetFront;
+
+    const selectedActor =
+      selectedObjectActor || selectedNodeActor || frameActor;
+
+    if (selectedTargetFront) {
+      targetFront = selectedTargetFront;
+    } else if (selectedActor) {
+      const selectedFront = this._commands.client.getFrontByID(selectedActor);
+      if (selectedFront) {
+        targetFront = selectedFront.targetFront;
+      }
+    }
+
+    const consoleFront = await targetFront.getFront("console");
+
+    // We call `evaluateJSAsync` RDP request, which immediately returns a simple `resultID`,
+    // for which we later receive a related `evaluationResult` RDP event, with the same resultID.
+    // The evaluation result will be contained in this RDP event.
+    let resultID;
+    const response = await new Promise(resolve => {
+      const offEvaluationResult = consoleFront.on(
+        "evaluationResult",
+        async packet => {
+          // In some cases, the evaluationResult event can be received before the call to
+          // evaluationJSAsync completes. So make sure to wait for the corresponding promise
+          // before handling the evaluationResult event.
+          await onEvaluateJSAsync;
+
+          if (packet.resultID === resultID) {
+            resolve(packet);
+            offEvaluationResult();
+          }
+        }
+      );
+
+      const onEvaluateJSAsync = consoleFront
+        .evaluateJSAsync({
+          text: expression,
+          eager: options.eager,
+          frameActor,
+          innerWindowID: options.innerWindowID,
+          mapped: options.mapped,
+          selectedNodeActor,
+          selectedObjectActor,
+          url: options.url,
+        })
+        .then(packet => {
+          resultID = packet.resultID;
+        });
+    });
+
+    // `response` is the packet sent via `evaluationResult` RDP event.
+    if (response.error) {
+      throw response;
+    }
+
+    if (response.result) {
+      response.result = getAdHocFrontOrPrimitiveGrip(
+        response.result,
+        consoleFront
+      );
+    }
+
+    if (response.helperResult?.object) {
+      response.helperResult.object = getAdHocFrontOrPrimitiveGrip(
+        response.helperResult.object,
+        consoleFront
+      );
+    }
+
+    if (response.exception) {
+      response.exception = getAdHocFrontOrPrimitiveGrip(
+        response.exception,
+        consoleFront
+      );
+    }
+
+    if (response.exceptionMessage) {
+      response.exceptionMessage = getAdHocFrontOrPrimitiveGrip(
+        response.exceptionMessage,
+        consoleFront
+      );
+    }
+
+    return response;
+  }
+}
+
+module.exports = ScriptCommand;