Function TryGetJSExtensionForFile

internal/module/util.go:178–197

TryGetJSExtensionForFile maps TS/JS/DTS extensions to the output JS-side extension. Returns an empty string if the extension is unsupported.

(fileName string, options *core.CompilerOptions)

// TryGetJSExtensionForFile maps TS/JS/DTS extensions to the output JS-side extension.
// Returns an empty string if the extension is unsupported.
func TryGetJSExtensionForFile(fileName string, options *core.CompilerOptions) string {
	ext := tspath.TryGetExtensionFromPath(fileName)
	switch ext {
	case tspath.ExtensionTs, tspath.ExtensionDts:
		return tspath.ExtensionJs
	case tspath.ExtensionTsx:
		if options.Jsx == core.JsxEmitPreserve {
			return tspath.ExtensionJsx
		}
		return tspath.ExtensionJs
	case tspath.ExtensionJs, tspath.ExtensionJsx, tspath.ExtensionJson:
		return ext
	case tspath.ExtensionDmts, tspath.ExtensionMts, tspath.ExtensionMjs:
		return tspath.ExtensionMjs
	case tspath.ExtensionDcts, tspath.ExtensionCts, tspath.ExtensionCjs:
		return tspath.ExtensionCjs
	default:
		return ""
	}
}