Allow --input-type to be used with --experimental-type

Author: GeoffreyBooth

doc/node.1

@@ -179,7 +179,7 @@ Use this flag to enable ShadowRealm support.
 Enable code coverage in the test runner.
 .
 .It Fl -experimental-type Ns = Ns Ar type
-Interpret as either ES modules or CommonJS modules input via --eval, --print or STDIN;
+Interpret as either ES modules or CommonJS modules input via --eval or STDIN, when --input-type is not specified;
 .js or extensionless files with no sibling or parent package.json;
 .js or extensionless files whose nearest parent package.json lacks a "type" field, unless under node_modules.
 .

lib/internal/main/check_syntax.js

@@ -60,7 +60,8 @@ function loadESMIfNeeded(cb) {
 async function checkSyntax(source, filename) {
   let isModule = true;
   if (filename === '[stdin]' || filename === '[eval]') {
-    isModule = getOptionValue('--input-type') === 'module' || getOptionValue('--experimental-type') === 'module';
+    isModule = getOptionValue('--input-type') === 'module' ||
+      (getOptionValue('--experimental-type') === 'module' && getOptionValue('--input-type') !== 'commonjs');
   } else {
     const { defaultResolve } = require('internal/modules/esm/resolve');
     const { defaultGetFormat } = require('internal/modules/esm/get_format');

lib/internal/main/eval_stdin.js

@@ -25,12 +25,14 @@ readStdin((code) => {
 
   const print = getOptionValue('--print');
   const loadESM = getOptionValue('--import').length > 0;
-  if (getOptionValue('--input-type') === 'module' || getOptionValue('--experimental-type') === 'module')
+  if (getOptionValue('--input-type') === 'module' ||
+    (getOptionValue('--experimental-type') === 'module' && getOptionValue('--input-type') !== 'commonjs')) {
     evalModule(code, print);
-  else
+  } else {
     evalScript('[stdin]',
                code,
                getOptionValue('--inspect-brk'),
                print,
                loadESM);
+  }
 });

lib/internal/main/eval_string.js

@@ -25,9 +25,10 @@ markBootstrapComplete();
 const source = getOptionValue('--eval');
 const print = getOptionValue('--print');
 const loadESM = getOptionValue('--import').length > 0 || getOptionValue('--experimental-loader').length > 0;
-if (getOptionValue('--input-type') === 'module' || getOptionValue('--experimental-type') === 'module')
+if (getOptionValue('--input-type') === 'module' ||
+  (getOptionValue('--experimental-type') === 'module' && getOptionValue('--input-type') !== 'commonjs')) {
   evalModule(source, print);
-else {
+} else {
   // For backward compatibility, we want the identifier crypto to be the
   // `node:crypto` module rather than WebCrypto.
   const isUsingCryptoIdentifier =

src/node_options.cc

@@ -127,11 +127,6 @@ void EnvironmentOptions::CheckOptions(std::vector<std::string>* errors,
     }
   }
 
-  if (!input_type.empty() && !type.empty()) {
-    errors->push_back("--input-type and --experimental-type cannot be used "
-                      "together");
-  }
-
   if (syntax_check_only && has_eval_string) {
     errors->push_back("either --check or --eval can be used, not both");
   }

test/es-module/test-esm-type-flag-string-input.mjs

@@ -27,4 +27,18 @@ describe('the type flag should change the interpretation of string input', { con
 
     match((await child.stdout.toArray()).toString(), /^function\r?\n$/);
   });
+
+  it('should be overridden by --input-type', async () => {
+    const { code, signal, stdout, stderr } = await spawnPromisified(process.execPath, [
+      '--experimental-type=module',
+      '--input-type=commonjs',
+      '--eval',
+      'console.log(require("process").version)',
+    ]);
+
+    strictEqual(stderr, '');
+    strictEqual(stdout, `${process.version}\n`);
+    strictEqual(code, 0);
+    strictEqual(signal, null);
+  });
 });