Function getMode

lib/dependencies/HarmonyExportImportedSpecifierDependency.js:309–469

(moduleGraph, dep, runtimeKey)

 * @returns {ExportMode} the export mode
 */
const getMode = (moduleGraph, dep, runtimeKey) => {
	const importedModule = moduleGraph.getModule(dep);

	if (!importedModule) {
		const mode = new ExportMode("missing");

		mode.userRequest = dep.userRequest;

		return mode;
	}

	const name = dep.name;
	const runtime = keyToRuntime(runtimeKey);
	const parentModule = /** @type {Module} */ (moduleGraph.getParentModule(dep));
	const exportsInfo = moduleGraph.getExportsInfo(parentModule);

	if (
		name
			? exportsInfo.getUsed(name, runtime) === UsageState.Unused
			: exportsInfo.isUsed(runtime) === false
	) {
		const mode = new ExportMode("unused");

		mode.name = name || "*";

		return mode;
	}

	const importedExportsType = importedModule.getExportsType(
		moduleGraph,
		/** @type {BuildMeta} */
		(parentModule.buildMeta).strictHarmonyModule
	);

	const ids = dep.getIds(moduleGraph);

	// Special handling for reexporting the default export
	// from non-namespace modules
	if (name && ids.length > 0 && ids[0] === "default") {
		switch (importedExportsType) {
			case "dynamic": {
				const mode = new ExportMode("reexport-dynamic-default");

				mode.name = name;

				return mode;
			}
			case "default-only":
			case "default-with-named": {
				const exportInfo = exportsInfo.getReadOnlyExportInfo(name);
				const mode = new ExportMode("reexport-named-default");

				mode.name = name;
				mode.partialNamespaceExportInfo = exportInfo;

				return mode;
			}
		}