refactor(tests): Use import instead of goog.bootstrap to load Blockly in mocha tests (#7406)

* fix(build): Have buildShims clean up up after itself

  We need to create a build/package.json file to allow node.js to
  load build/src/core/blockly.js and the other chunk entry points
  as ES modules (it forcibly assumes .js means CJS even if one is
  trying to import, unless package.json says {"type": "module"}),
  but this interferes with scripts/migration/js2ts doing a
  require('build/deps.js'), which is _not_ an ES module.

  Specific error message was:

  /Users/cpcallen/src/blockly/scripts/migration/js2ts:56
  require(path.resolve(__dirname, '../../build/deps.js'));
  ^

  Error [ERR_REQUIRE_ESM]: require() of ES Module
  /Users/cpcallen/src/blockly/build/deps.js from /Users/cpcallen/src/blockly/scripts/migration/js2ts
  not supported.
  deps.js is treated as an ES module file as it is a .js file whose
  nearest parent package.json contains "type": "module" which
  declares all .js files in that package scope as ES modules.
  Instead rename deps.js to end in .cjs, change the requiring code
  to use dynamic import() which is available in all CommonJS
  modules, or change "type": "module" to "type": "commonjs" in
  /Users/cpcallen/src/blockly/build/package.json to treat all .js
  files as CommonJS (using .mjs for all ES modules instead).

      at Object.<anonymous> (/Users/cpcallen/src/blockly/scripts/migration/js2ts:56:1) {
    code: 'ERR_REQUIRE_ESM'
  }

* chore(tests): Reorder to put interesting script nearer top of file

* chore(tests): Add missing imports of closure/goog/goog.js

  These modules were depending on being loaded via the
  debug module loader, which cannot be used without first loading
  base.js as a script, and thereby defining goog.declareModuleId
  as a side effect—but if they are to be loaded via direct import
  statements then they need to actually import their own
  dependencies.

  This is a temporary measure as soon the goog.declareMouleId
  calls can themselves be deleted.

* refactor(tests): Use import instead of bootstrap to load Blockly

* chores(build): Stop generating deps.mocha.js

  This file was only needed by tests/mocha/index.html's use of
  the debug module loader (via bootstrap.js), which has now been
  removed.

* chore(tests): Remove unneeded goog.declareModuleId calls

  These were only needed because these modules were previously
  being loaded by goog.require and/or goog.bootstrap.

* chores(tests): Remove dead code

  We are fully committed to proper modules now.

scripts/gulpfiles/build_tasks.js

@@ -22,7 +22,7 @@ const closureCompiler = require('google-closure-compiler').gulp();
 const argv = require('yargs').argv;
 const {rimraf} = require('rimraf');
 
-const {BUILD_DIR, DEPS_FILE, RELEASE_DIR, TEST_DEPS_FILE, TSC_OUTPUT_DIR, TYPINGS_BUILD_DIR} = require('./config');
+const {BUILD_DIR, DEPS_FILE, RELEASE_DIR, TSC_OUTPUT_DIR, TYPINGS_BUILD_DIR} = require('./config');
 const {getPackageJson} = require('./helper_tasks');
 
 const {posixPath, quote} = require('../helpers');
@@ -305,36 +305,17 @@ function buildJavaScript(done) {
  * This task updates DEPS_FILE (deps.js), used by the debug module
  * loader (via bootstrap.js) when loading Blockly in uncompiled mode.
  *
- * Also updates TEST_DEPS_FILE (deps.mocha.js), used by the mocha test
- * suite.
- *
  * Prerequisite: buildJavaScript.
  */
 function buildDeps() {
   const roots = [
     path.join(TSC_OUTPUT_DIR, 'closure', 'goog', 'base.js'),
     TSC_OUTPUT_DIR,
-    'tests/mocha',
   ];
 
   /** Maximum buffer size, in bytes for child process stdout/stderr. */
   const MAX_BUFFER_SIZE = 10 * 1024 * 1024;
 
-  /**
-   * Filter a string to extract lines containing (or not containing) the
-   * specified target string.
-   *
-   * @param {string} text Text to filter.
-   * @param {string} target String to search for.
-   * @param {boolean?} exclude If true, extract only non-matching lines.
-   * @returns {string} Filtered text.
-   */
-  function filter(text, target, exclude) {
-    return text.split('\n')
-        .filter((line) => Boolean(line.match(target)) !== Boolean(exclude))
-        .join('\n');
-  }
-
   /**
    * Log unexpected diagnostics, after removing expected warnings.
    *
@@ -374,9 +355,7 @@ error message above, try running:
           } else {
             log(stderr);
             // Anything not about mocha goes in DEPS_FILE.
-            fs.writeFileSync(DEPS_FILE, filter(stdout, 'tests/mocha', true));
-            // Anything about mocha does in TEST_DEPS_FILE.
-            fs.writeFileSync(TEST_DEPS_FILE, filter(stdout, 'tests/mocha'));
+            fs.writeFileSync(DEPS_FILE, stdout);
             resolve();
           }
         });
@@ -691,10 +670,8 @@ async function buildShims() {
   // ESM, but fortunately we don't attempt to import or require this
   // file from node.js - we only feed it to Closure Compiler, which
   // uses the type information in deps.js rather than package.json.
-  await fsPromises.writeFile(
-    path.join(BUILD_DIR, 'package.json'),
-    '{"type": "module"}'
-  );
+  const TMP_PACKAGE_JSON = path.join(BUILD_DIR, 'package.json');
+  await fsPromises.writeFile(TMP_PACKAGE_JSON, '{"type": "module"}');
 
   // Import each entrypoint module, enumerate its exports, and write
   // a shim to load the chunk either by importing the entrypoint
@@ -723,6 +700,8 @@ ${Object.keys(exports).map((name) => `  ${name},`).join('\n')}
 );
 `);
   }));
+
+  await fsPromises.rm(TMP_PACKAGE_JSON);
 }
 
 

scripts/gulpfiles/config.js

@@ -28,9 +28,6 @@ exports.BUILD_DIR = 'build';
 // Dependencies file (used by bootstrap.js in uncompiled mode):
 exports.DEPS_FILE = path.join(exports.BUILD_DIR, 'deps.js');
 
-// Mocha test dependencies file (used by tests/mocha/index.html):
-exports.TEST_DEPS_FILE = path.join(exports.BUILD_DIR, 'deps.mocha.js');
-
 // Directory to write typings output to.
 exports.TYPINGS_BUILD_DIR = path.join(exports.BUILD_DIR, 'declarations');