chore(esm): remove code for Node v12 (#4874)

mochajs · Apr 24, 2022 · f6695f0 · f6695f0
1 parent 59f6192
commit f6695f0
Show file tree

Hide file tree

Showing 4 changed files with 42 additions and 95 deletions.
diff --git a/lib/nodejs/esm-utils.js b/lib/nodejs/esm-utils.js
@@ -10,7 +10,7 @@ const formattedImport = async file => {
       // the location of the syntax error in the error thrown.
       // This is problematic because the user can't see what file has the problem,
       // so we add the file location to the error.
-      // This `if` should be removed once Node.js fixes the problem.
+      // TODO: remove once Node.js fixes the problem.
       if (
         err instanceof SyntaxError &&
         err.message &&
@@ -30,64 +30,52 @@ const formattedImport = async file => {
   return import(file);
 };
 
-const hasStableEsmImplementation = (() => {
-  const [major, minor] = process.version.split('.');
-  // ESM is stable from v12.22.0 onward
-  // https://nodejs.org/api/esm.html#esm_modules_ecmascript_modules
-  const majorNumber = parseInt(major.slice(1), 10);
-  const minorNumber = parseInt(minor, 10);
-  return majorNumber > 12 || (majorNumber === 12 && minorNumber >= 22);
-})();
-
-exports.requireOrImport = hasStableEsmImplementation
-  ? async file => {
-      if (path.extname(file) === '.mjs') {
-        return formattedImport(file);
-      }
+exports.requireOrImport = async file => {
+  if (path.extname(file) === '.mjs') {
+    return formattedImport(file);
+  }
+  try {
+    return dealWithExports(await formattedImport(file));
+  } catch (err) {
+    if (
+      err.code === 'ERR_MODULE_NOT_FOUND' ||
+      err.code === 'ERR_UNKNOWN_FILE_EXTENSION' ||
+      err.code === 'ERR_UNSUPPORTED_DIR_IMPORT'
+    ) {
       try {
-        return dealWithExports(await formattedImport(file));
-      } catch (err) {
+        // Importing a file usually works, but the resolution of `import` is the ESM
+        // resolution algorithm, and not the CJS resolution algorithm. We may have
+        // failed because we tried the ESM resolution, so we try to `require` it.
+        return require(file);
+      } catch (requireErr) {
         if (
-          err.code === 'ERR_MODULE_NOT_FOUND' ||
-          err.code === 'ERR_UNKNOWN_FILE_EXTENSION' ||
-          err.code === 'ERR_UNSUPPORTED_DIR_IMPORT'
+          requireErr.code === 'ERR_REQUIRE_ESM' ||
+          (requireErr instanceof SyntaxError &&
+            requireErr
+              .toString()
+              .includes('Cannot use import statement outside a module'))
         ) {
-          try {
-            // Importing a file usually works, but the resolution of `import` is the ESM
-            // resolution algorithm, and not the CJS resolution algorithm. So in this case
-            // if we fail, we may have failed because we tried the ESM resolution and failed
-            // So we try to `require` it
-            return require(file);
-          } catch (requireErr) {
-            if (
-              requireErr.code === 'ERR_REQUIRE_ESM' ||
-              (requireErr instanceof SyntaxError &&
-                requireErr
-                  .toString()
-                  .includes('Cannot use import statement outside a module'))
-            ) {
-              // ERR_REQUIRE_ESM happens when the test file is a JS file, but via type:module is actually ESM,
-              // AND has an import to a file that doesn't exist.
-              // This throws an `ERR_MODULE_NOT_FOUND` error above,
-              // and when we try to `require` it here, it throws an `ERR_REQUIRE_ESM`.
-              // What we want to do is throw the original error (the `ERR_MODULE_NOT_FOUND`),
-              // and not the `ERR_REQUIRE_ESM` error, which is a red herring.
-              //
-              // SyntaxError happens when in an edge case: when we're using an ESM loader that loads
-              // a `test.ts` file (i.e. unrecognized extension), and that file includes an unknown
-              // import (which thows an ERR_MODULE_NOT_FOUND). require-ing it will throw the
-              // syntax error, because we cannot require a file that has import-s.
-              throw err;
-            } else {
-              throw requireErr;
-            }
-          }
-        } else {
+          // ERR_REQUIRE_ESM happens when the test file is a JS file, but via type:module is actually ESM,
+          // AND has an import to a file that doesn't exist.
+          // This throws an `ERR_MODULE_NOT_FOUND` error above,
+          // and when we try to `require` it here, it throws an `ERR_REQUIRE_ESM`.
+          // What we want to do is throw the original error (the `ERR_MODULE_NOT_FOUND`),
+          // and not the `ERR_REQUIRE_ESM` error, which is a red herring.
+          //
+          // SyntaxError happens when in an edge case: when we're using an ESM loader that loads
+          // a `test.ts` file (i.e. unrecognized extension), and that file includes an unknown
+          // import (which throws an ERR_MODULE_NOT_FOUND). `require`-ing it will throw the
+          // syntax error, because we cannot require a file that has `import`-s.
           throw err;
+        } else {
+          throw requireErr;
         }
       }
+    } else {
+      throw err;
     }
-  : implementationOfRequireOrImportForUnstableEsm;
+  }
+};
 
 function dealWithExports(module) {
   if (module.default) {
@@ -104,21 +92,3 @@ exports.loadFilesAsync = async (files, preLoadFunc, postLoadFunc) => {
     postLoadFunc(file, result);
   }
 };
-
-/* istanbul ignore next */
-async function implementationOfRequireOrImportForUnstableEsm(file) {
-  if (path.extname(file) === '.mjs') {
-    return formattedImport(file);
-  }
-  // This is currently the only known way of figuring out whether a file is CJS or ESM in
-  // Node.js that doesn't necessitate calling `import` first.
-  try {
-    return require(file);
-  } catch (err) {
-    if (err.code === 'ERR_REQUIRE_ESM') {
-      return formattedImport(file);
-    } else {
-      throw err;
-    }
-  }
-}
diff --git a/test/integration/diffs.spec.js b/test/integration/diffs.spec.js
@@ -69,12 +69,6 @@ describe('diffs', function () {
   var diffs, expected;
 
   before(function (done) {
-    // @TODO: It should be removed when Node.js 10 LTS is not supported.
-    const nodeVersion = parseInt(process.version.match(/^v(\d+)\./)[1], 10);
-    if (nodeVersion === 10) {
-      this.skip();
-    }
-
     run('diffs/diffs.fixture.js', [], function (err, res) {
       if (err) {
         done(err);

diff --git a/test/integration/glob.spec.js b/test/integration/glob.spec.js
@@ -187,13 +187,6 @@ var testGlob = {
   })
 };
 
-var isFlakeyNode = (function () {
-  var version = process.versions.node.split('.');
-  return (
-    version[0] === '0' && version[1] === '10' && process.platform === 'win32'
-  );
-})();
-
 function execMochaWith(validate) {
   return function execMocha(glob, assertOn, done) {
     exec(
@@ -206,12 +199,8 @@ function execMochaWith(validate) {
       function (error, stdout, stderr) {
         try {
           validate(error, stderr);
-          if (isFlakeyNode && error && stderr === '') {
-            execMocha(glob, assertOn, done);
-          } else {
-            assertOn({stdout: stdout, stderr: stderr});
-            done();
-          }
+          assertOn({stdout: stdout, stderr: stderr});
+          done();
         } catch (assertion) {
           done(assertion);
         }

diff --git a/test/integration/no-diff.spec.js b/test/integration/no-diff.spec.js
@@ -6,12 +6,6 @@ var run = helpers.runMocha;
 describe('no-diff', function () {
   describe('when enabled', function () {
     it('should not display a diff', function (done) {
-      // @TODO: It should be removed when Node.js 10 LTS is not supported.
-      const nodeVersion = parseInt(process.version.match(/^v(\d+)\./)[1], 10);
-      if (nodeVersion === 10) {
-        this.skip();
-      }
-
       run('no-diff.fixture.js', ['--no-diff'], function (err, res) {
         if (err) {
           done(err);