JS -- Add a sandbox based on quickjs

* quickjs-eval.js has been generated using https://github.com/mozilla/pdf.js.quickjs/
 * lazy load of sandbox code
 * Rewrite tests to use the sandbox
 * Add a task `watch-sandbox` which update bundle pdf.sandbox.js on change in the sandbox code

src/scripting_api/initialization.js

@@ -22,7 +22,7 @@ import { ProxyHandler } from "./proxy.js";
 import { Util } from "./util.js";
 import { ZoomType } from "./constants.js";
 
-function initSandbox({ data, extra, out, testMode = false }) {
+function initSandbox({ data, extra, out }) {
   const proxyHandler = new ProxyHandler(data.dispatchEventName);
   const { send, crackURL } = extra;
   const doc = new Doc({
@@ -58,14 +58,6 @@ function initSandbox({ data, extra, out, testMode = false }) {
       out[name] = aform[name].bind(aform);
     }
   }
-
-  if (
-    (typeof PDFJSDev === "undefined" ||
-      PDFJSDev.test("!PRODUCTION || TESTING")) &&
-    testMode
-  ) {
-    out._app = app;
-  }
 }
 
 export { initSandbox };

src/scripting_api/quickjs-sandbox.js

@@ -0,0 +1,103 @@
+/* Copyright 2020 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import ModuleLoader from "../../external/quickjs/quickjs-eval.js";
+
+class Sandbox {
+  constructor(module, testMode) {
+    this._evalInSandbox = module.cwrap("evalInSandbox", null, [
+      "string",
+      "int",
+    ]);
+    this._dispatchEventName = null;
+    this._module = module;
+    this._testMode = testMode;
+    this._alertOnError = 1;
+  }
+
+  create(data) {
+    const sandboxData = JSON.stringify(data);
+    const extra = [
+      "send",
+      "setTimeout",
+      "clearTimeout",
+      "setInterval",
+      "clearInterval",
+      "crackURL",
+    ];
+    const extraStr = extra.join(",");
+    let code = [
+      "exports = Object.create(null);",
+      "module = Object.create(null);",
+      // Next line is replaced by code from initialization.js
+      // when we create the bundle for the sandbox.
+      "/* INITIALIZATION_CODE */",
+      `data = ${sandboxData};`,
+      `module.exports.initSandbox({ data, extra: {${extraStr}}, out: this});`,
+      "delete exports;",
+      "delete module;",
+      "delete data;",
+    ];
+    if (!this._testMode) {
+      code = code.concat(extra.map(name => `delete ${name};`));
+      code.push("delete debugMe;");
+    }
+    this._evalInSandbox(code.join("\n"), this._alertOnError);
+    this._dispatchEventName = data.dispatchEventName;
+  }
+
+  dispatchEvent(event) {
+    if (this._dispatchEventName === null) {
+      throw new Error("Sandbox must have been initialized");
+    }
+    event = JSON.stringify(event);
+    this._evalInSandbox(
+      `app["${this._dispatchEventName}"](${event});`,
+      this._alertOnError
+    );
+  }
+
+  dumpMemoryUse() {
+    this._module.ccall("dumpMemoryUse", null, []);
+  }
+
+  nukeSandbox() {
+    this._dispatchEventName = null;
+    this._module.ccall("nukeSandbox", null, []);
+    this._module = null;
+    this._evalInSandbox = null;
+  }
+
+  evalForTesting(code, key) {
+    if (this._testMode) {
+      this._evalInSandbox(
+        `send({ id: "${key}", result: ${code} });`,
+        this._alertOnError
+      );
+    }
+  }
+}
+
+function QuickJSSandbox(testMode = false) {
+  testMode =
+    testMode &&
+    (typeof PDFJSDev === "undefined" ||
+      PDFJSDev.test("!PRODUCTION || TESTING"));
+  return ModuleLoader().then(module => {
+    return new Sandbox(module, testMode);
+  });
+}
+
+export { QuickJSSandbox };

src/scripting_api/util.js

@@ -49,6 +49,9 @@ class Util extends PDFObject {
   }
 
   crackURL(cURL) {
+    if (typeof cURL !== "string") {
+      throw new TypeError("First argument of util.crackURL must be a string");
+    }
     return this._crackURL(cURL);
   }