Mocha tests for React (jsx) aren't parsed as jsx if test filename has .js extension

Hi, This is a clone of an issue i've opened on the main SWC repo

It might be better suited for this repo than the main SWC one.

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Repo - https://github.com/yairEO/swc-js-extension-fails-with-jsx-content

Describe the bug

Hi, I am trying to convert a large project from Mocha + babel to Mocha + SWC, but get errors if the test file extension ends with .js and not .jsx. I have hundreds of files like this.

Renaming one of them makes SWC compile it correctly, but I really prefer keeping the tests files with the .js extension.

the project is based on React v16, so every component and its test file has the React import:

import React from 'react';

I would assume SWC would be smart enough to automatically know the content of the file is JSX...

Input code

No response

Config

{
    "$schema": "https://json.schemastore.org/swcrc",
    "jsc": {
      "parser": {
        "syntax": "ecmascript",
        "jsx": true,
        "dynamicImport": false,
        "privateMethod": true,
        "functionBind": false,
        "exportDefaultFrom": true,
        "exportNamespaceFrom": false,
        "decorators": true,
        "decoratorsBeforeExport": true,
        "topLevelAwait": false,
        "importMeta": false
      },
      "transform": {
        "legacyDecorator": true,
        "react": {
          "pragma": "React.createElement",
          "pragmaFrag": "React.Fragment",
          "throwIfNamespace": true,
          "development": false,
          "useBuiltins": false
        },
        "optimizer": {
          "globals": {
            "vars": {
              "__DEBUG__": "true"
            }
          }
        }
      },
      "target": "es5",
      "loose": false,
      "externalHelpers": false,
      // Requires v1.2.50 or upper and requires target to be es2016 or upper.
      "keepClassNames": false
    },
    "minify": false
}

Expected behavior

Should transpile JSX for .js files automatically

Actual behavior

No response

Version

1.5.5

Additional context

Am using these packages:

"@swc-node/register": "1.5.5",
"swc": "1.0.11",
"mocha": "9.2.2",

Running the tests with this .mocharc:

{
  "exit": true,
  "color": true,
  "require": ["@swc-node/register", "test/register.js", "test/setup.js"],
  "ignore": "node_modules"
}

Start with @swc-node/register and its handling of Mocha's .js test files; reproduce the report using the shown .mocharc and SWC parser configuration. Compare processing of .js and .jsx inputs, then add coverage for JSX in .js tests and verify the expected transpilation.