feat(48702): Emit for dynamic import (import()) when target >= ES2020 and module == None (#50942)

src/compiler/transformers/module/module.ts

@@ -850,6 +850,9 @@ export function transformModule(context: TransformationContext): (x: SourceFile
     }
 
     function visitImportCallExpression(node: ImportCall): Expression {
+        if (moduleKind === ModuleKind.None && languageVersion >= ScriptTarget.ES2020) {
+            return visitEachChild(node, visitor, context);
+        }
         const externalModuleName = getExternalModuleNameLiteral(factory, node, currentSourceFile, host, resolver, compilerOptions);
         const firstArgument = visitNode(firstOrUndefined(node.arguments), visitor, isExpression);
         // Only use the external module name if it differs from the first argument. This allows us to preserve the quote style of the argument on output.

tests/baselines/reference/moduleNoneDynamicImport(target=es2015).js

@@ -0,0 +1,11 @@
+//// [tests/cases/compiler/moduleNoneDynamicImport.ts] ////
+
+//// [a.ts]
+const foo = import("./b");
+
+//// [b.js]
+export default 1;
+
+
+//// [a.js]
+const foo = Promise.resolve().then(() => require("b"));

tests/baselines/reference/moduleNoneDynamicImport(target=es2015).symbols

@@ -0,0 +1,9 @@
+=== /a.ts ===
+const foo = import("./b");
+>foo : Symbol(foo, Decl(a.ts, 0, 5))
+>"./b" : Symbol("/b", Decl(b.js, 0, 0))
+
+=== /b.js ===
+
+export default 1;
+

tests/baselines/reference/moduleNoneDynamicImport(target=es2015).types

@@ -0,0 +1,10 @@
+=== /a.ts ===
+const foo = import("./b");
+>foo : Promise<typeof import("/b")>
+>import("./b") : Promise<typeof import("/b")>
+>"./b" : "./b"
+
+=== /b.js ===
+
+export default 1;
+

tests/baselines/reference/moduleNoneDynamicImport(target=es2020).js

@@ -0,0 +1,11 @@
+//// [tests/cases/compiler/moduleNoneDynamicImport.ts] ////
+
+//// [a.ts]
+const foo = import("./b");
+
+//// [b.js]
+export default 1;
+
+
+//// [a.js]
+const foo = import("./b");

tests/baselines/reference/moduleNoneDynamicImport(target=es2020).symbols

@@ -0,0 +1,9 @@
+=== /a.ts ===
+const foo = import("./b");
+>foo : Symbol(foo, Decl(a.ts, 0, 5))
+>"./b" : Symbol("/b", Decl(b.js, 0, 0))
+
+=== /b.js ===
+
+export default 1;
+

tests/baselines/reference/moduleNoneDynamicImport(target=es2020).types

@@ -0,0 +1,10 @@
+=== /a.ts ===
+const foo = import("./b");
+>foo : Promise<typeof import("/b")>
+>import("./b") : Promise<typeof import("/b")>
+>"./b" : "./b"
+
+=== /b.js ===
+
+export default 1;
+

tests/cases/compiler/moduleNoneDynamicImport.ts

@@ -0,0 +1,9 @@
+// @allowJs: true
+// @target: es2015,es2020
+// @module: none
+// @outFile: /a.js
+// @filename: /a.ts
+const foo = import("./b");
+
+// @filename: /b.js
+export default 1;