fixup ES6 import support (alongside commonjs and closure modules)

This work is largely based on protocolbuffers#156

Author: dibenede

MODULE.bazel.lock

@@ -48,6 +48,8 @@ if (typeof exports === 'object') {
     'array': goog.array,
     'object': goog.object,
     'requireType': goog.requireType,
+    'typeOf': goog.typeOf,
+    'inherits': goog.inherits,
   };
 
   exports['jspb'] = {

commonjs/export_testdeps.js

@@ -0,0 +1,14 @@
+import googleProtobuf from 'google-protobuf';
+import * as test7_pb from './test7/test7_pb.mjs';
+
+const global = globalThis;
+googleProtobuf.exportSymbol('jspb.Message', googleProtobuf.Message, global);
+googleProtobuf.exportSymbol('proto.jspb.test.framing.FramingMessage', test7_pb.FramingMessage, global);
+
+describe('Import test suite', () => {
+  it('testImportedMessage', () => {
+    const framing1 = new proto.jspb.test.framing.FramingMessage([]);
+    const framing2 = new proto.jspb.test.framing.FramingMessage([]);
+    expect(framing1.toObject()).toEqual(framing2.toObject());
+  });
+});

es6/import_test.js

@@ -0,0 +1,72 @@
+/**
+ * @fileoverview Utility to translate test files to ES6 imports.
+ */
+
+var lineReader = require('readline').createInterface({
+  input: process.stdin,
+  output: process.stdout
+});
+
+function tryStripPrefix(str, prefix) {
+  if (str.lastIndexOf(prefix) !== 0) {
+    throw "String: " + str + " didn't start with: " + prefix;
+  }
+  return str.substr(prefix.length);
+}
+
+function camelCase(str) {
+  var ret = '';
+  var ucaseNext = false;
+  for (var i = 0; i < str.length; i++) {
+    if (str[i] == '-') {
+      ucaseNext = true;
+    } else if (ucaseNext) {
+      ret += str[i].toUpperCase();
+      ucaseNext = false;
+    } else {
+      ret += str[i];
+    }
+  }
+  return ret;
+}
+
+var module = null;
+var pkg = null;
+
+// Header
+console.log("import googleProtobuf from 'google-protobuf';");
+console.log("import testdeps from 'testdeps_commonjs';");
+console.log("globalThis.COMPILED = testdeps.COMPILED;");
+console.log("globalThis.goog = testdeps.goog;");
+console.log("globalThis.googleProtobuf = googleProtobuf;");
+console.log("");
+
+lineReader.on('line', function (line) {
+  const isModuleGet = line.match(/(.*)goog\.module\.get\('([^']*)'\)([^;]*);/);
+  if (isModuleGet) {
+    const fullSym = isModuleGet[2];
+    console.log(isModuleGet[1] + "testdeps." + fullSym + isModuleGet[3]);
+    return;
+  }
+  var isRequire = line.match(/goog\.require\('([^']*)'\)/);
+  var isLoadFromFile = line.match(/CommonJS-LoadFromFile: (\S*) (.*)/);
+  var isSetTestOnly = line.match(/goog.setTestOnly()/);
+  if (isRequire) {
+    if (module) {
+      var fullSym = isRequire[1];
+      if (fullSym.match(/^jspb\./)) return;
+      var sym = tryStripPrefix(fullSym, pkg);
+      console.log("googleProtobuf.exportSymbol('" + fullSym + "', " + module + sym + ', globalThis);');
+    }
+  } else if (isLoadFromFile) {
+    var module_path = isLoadFromFile[1].split('/');
+    module = camelCase(module_path[module_path.length - 1]);
+    pkg = isLoadFromFile[2];
+
+    if (module != "googleProtobuf") {
+      console.log("import * as " + module + " from './" + isLoadFromFile[1] + ".mjs';");
+    }
+  } else if (!isSetTestOnly) {
+    console.log(line);
+  }
+});

es6/rewrite_tests_for_es6.js

@@ -0,0 +1,29 @@
+import googleProtobuf from 'google-protobuf';
+import * as test9_pb from './protos/test9_pb.mjs';
+import * as test10_pb from './protos/test10_pb.mjs';
+
+const global = globalThis;
+
+describe('Strict test suite', () => {
+  it('testImportedMessage', () => {
+    const simple1 = new test9_pb.Simple9()
+    const simple2 = new test9_pb.Simple9()
+    expect(simple1.toObject()).toEqual(simple2.toObject());
+  });
+
+  it('testGlobalScopePollution', () => {
+    expect(global.jspb.exttest).toBeUndefined();
+  });
+
+  describe('with imports', () => {
+    it('testImportedMessage', () => {
+      const simple1 = new test10_pb.Simple10()
+      const simple2 = new test10_pb.Simple10()
+      expect(simple1.toObject()).toEqual(simple2.toObject());
+    });
+
+    it('testGlobalScopePollution', () => {
+      expect(global.jspb.exttest).toBeUndefined();
+    });
+  });
+});