Re-implement working dev-sandbox/watch-dev-sandbox gulp-tasks

Compared to the, previously removed, `sandbox`/`watch-sandbox` gulp-tasks, these ones should work even when run against an non-existent/empty `build`-folder.

Also, to ensure that the development viewer actually works out-of-the-box, `gulp server` will now also include `gulp watch-dev-sandbox` to remove the need to *manually* invoke the build-tasks.

Finally, this patch also removes the `web/devcom.js` file since it shouldn't actually be needed, assuming that the "sandbox"-loading code in the `web/genericcom.js` file is actually *correctly* implemented.

gulpfile.js

@@ -173,9 +173,15 @@ function createStringSource(filename, content) {
 function createWebpackConfig(
   defines,
   output,
-  { disableSourceMaps = false, disableLicenseHeader = false } = {}
+  {
+    disableVersionInfo = false,
+    disableSourceMaps = false,
+    disableLicenseHeader = false,
+  } = {}
 ) {
-  var versionInfo = getVersionJSON();
+  const versionInfo = !disableVersionInfo
+    ? getVersionJSON()
+    : { version: 0, commit: 0 };
   var bundleDefines = builder.merge(defines, {
     BUNDLE_VERSION: versionInfo.version,
     BUNDLE_BUILD: versionInfo.commit,
@@ -359,8 +365,9 @@ function createScriptingBundle(defines, extraOptions = undefined) {
     .pipe(replaceJSRootName(scriptingAMDName, "pdfjsScripting"));
 }
 
-function createTemporaryScriptingBundle(defines) {
+function createTemporaryScriptingBundle(defines, extraOptions = undefined) {
   return createScriptingBundle(defines, {
+    disableVersionInfo: !!(extraOptions && extraOptions.disableVersionInfo),
     disableSourceMaps: true,
     disableLicenseHeader: true,
   }).pipe(gulp.dest(TMP_DIR));
@@ -1711,16 +1718,57 @@ gulp.task(
   })
 );
 
-gulp.task("server", function () {
-  console.log();
-  console.log("### Starting local server");
+gulp.task(
+  "dev-sandbox",
+  gulp.series(
+    function scripting() {
+      const defines = builder.merge(DEFINES, { GENERIC: true, TESTING: true });
+      return createTemporaryScriptingBundle(defines, {
+        disableVersionInfo: true,
+      });
+    },
+    function () {
+      console.log();
+      console.log("### Building development sandbox");
 
-  var WebServer = require("./test/webserver.js").WebServer;
-  var server = new WebServer();
-  server.port = 8888;
-  server.start();
+      const defines = builder.merge(DEFINES, { GENERIC: true, TESTING: true });
+      const sandboxDir = BUILD_DIR + "dev-sandbox/";
+
+      rimraf.sync(sandboxDir);
+
+      return createSandboxBundle(defines, {
+        disableVersionInfo: true,
+      }).pipe(gulp.dest(sandboxDir));
+    }
+  )
+);
+
+gulp.task("watch-dev-sandbox", function () {
+  gulp.watch(
+    [
+      "src/pdf.{sandbox,scripting}.js",
+      "src/scripting_api/*.js",
+      "src/shared/scripting_utils.js",
+      "external/quickjs/*.js",
+    ],
+    { ignoreInitial: false },
+    gulp.series("dev-sandbox")
+  );
 });
 
+gulp.task(
+  "server",
+  gulp.parallel("watch-dev-sandbox", function () {
+    console.log();
+    console.log("### Starting local server");
+
+    var WebServer = require("./test/webserver.js").WebServer;
+    var server = new WebServer();
+    server.port = 8888;
+    server.start();
+  })
+);
+
 gulp.task("clean", function (done) {
   console.log();
   console.log("### Cleaning up project builds");

web/app_options.js

@@ -223,14 +223,6 @@ const defaultOptions = {
     value: false,
     kind: OptionKind.API,
   },
-  scriptingSrc: {
-    /** @type {string} */
-    value:
-      typeof PDFJSDev === "undefined" || !PDFJSDev.test("PRODUCTION")
-        ? "../build/generic/build/pdf.sandbox.js"
-        : "../build/pdf.sandbox.js",
-    kind: OptionKind.VIEWER,
-  },
   verbosity: {
     /** @type {number} */
     value: 1,
@@ -265,6 +257,14 @@ if (
     value: typeof navigator !== "undefined" ? navigator.language : "en-US",
     kind: OptionKind.VIEWER,
   };
+  defaultOptions.sandboxBundleSrc = {
+    /** @type {string} */
+    value:
+      typeof PDFJSDev === "undefined" || !PDFJSDev.test("PRODUCTION")
+        ? "../build/dev-sandbox/pdf.sandbox.js"
+        : "../build/pdf.sandbox.js",
+    kind: OptionKind.VIEWER,
+  };
 }
 
 const userOptions = Object.create(null);

web/devcom.js

@@ -1,43 +0,0 @@
-/* Copyright 2017 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 { DefaultExternalServices, PDFViewerApplication } from "./app.js";
-import { loadScript, shadow } from "pdfjs-lib";
-
-const DevCom = {};
-
-class DevExternalServices extends DefaultExternalServices {
-  static get scripting() {
-    const promise = loadScript("../build/pdf.sandbox.js").then(() => {
-      return window.pdfjsSandbox.QuickJSSandbox();
-    });
-    const sandbox = {
-      createSandbox(data) {
-        promise.then(sbx => sbx.create(data));
-      },
-      dispatchEventInSandbox(event) {
-        promise.then(sbx => sbx.dispatchEvent(event));
-      },
-      destroySandbox() {
-        promise.then(sbx => sbx.nukeSandbox());
-      },
-    };
-
-    return shadow(this, "scripting", sandbox);
-  }
-}
-PDFViewerApplication.externalServices = DevExternalServices;
-
-export { DevCom };

web/genericcom.js

@@ -53,7 +53,7 @@ class GenericExternalServices extends DefaultExternalServices {
   }
 
   static get scripting() {
-    const promise = loadScript(AppOptions.get("scriptingSrc")).then(() => {
+    const promise = loadScript(AppOptions.get("sandboxBundleSrc")).then(() => {
       return window.pdfjsSandbox.QuickJSSandbox();
     });
     const sandbox = {

web/viewer.js

@@ -56,9 +56,6 @@ if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("GENERIC")) {
 if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("CHROME")) {
   require("./chromecom.js");
 }
-if (typeof PDFJSDev === "undefined") {
-  import("./devcom.js");
-}
 if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("CHROME || GENERIC")) {
   require("./pdf_print_service.js");
 }